Changed the oil and filter a few months ago and noticed the pressure a bit lower than usual. Used Comna classic 20w50 and just assumed it might be a bit thinner than the previous oil.
Started her up yesterday afternoon standing for a while and the pressure went straight up to 40psi which is the normal cold pressure but dropped to about 20 when revved, normally does the opposite. Also sounds a bit graunchy.
When I get a chance I'll drain her down and take the pump cover off, see if there's anything odd in there.
Any ideas?
Check the oil relief valves and for any shiny particles in the oil.
Cheers Keith's
Soon as I'm over the flu ill have a go at it, forgot those valves tucked underneath, good call
Thats curious - almost exactly where I am at the moment
Last trip out, engine fired up with full oil pressure, but when going along slowly or tickover, the oil pressure drops quite dramatically to the point I`m not actually happy driving it.
Need to also drain it out and see what it going on inside and I`m going to remove and service those oil relief bits as well.
Interesting to share findings on here ;-)up
Dave, yours is how mine started, almost as if the oil was too thin. Now it's reversed and drops when the revs increase.
A common issue giving oil pressure reading oddities is from engines that have had silicone based sealants used on them. Bits of silicone don`t dissolve in hot engine oil. Old school wax based sealants do. It could well be that a bit of crap is in one of the relief valves or both if the engine is based on a 1600 block. If crap has got to the relief valve/s it will probably be in the wrong side of the mesh filter as well. (Assuming you have the original strainer still fitted).
Got an external filter fitted, I know that doesn't catch everything, has anyone got a diagram showing the oil path routes?
Here is a good one Dave https://zuczek1302.com/2018/12/21/the-air-cooled-vw-engine-oil-system/
That's brilliant keith, thanks
Had a similar problem a few years ago it was a sticking valve, replaced them and the springs with CSP items.
My engine is the later type with the two valve setup.
VW Oil Control Valves (http://www.chris-jordan.org.uk/_media/vw-oil-control-valves.pdf)
Cheers Chris
That's a useful little article Chris, were did yo7u find it?
From the book How to rebuild your Volkswagen air cooled engine by Tom Wilson
;-)up
Mine is a 2 litre lump, so slightly different, but I guess also similar enough with the pressure relief valves, which is where I was heading -
However, finally got around to draining the oil out over the weekend into a large oil catch can underneath, and I swear I spotted something, but not certain. As I removed the sump nut and all started to drain, it was almost as if I had a small amount of "gloopy" liquid come through, maybe an egg cup full, but almost runny jelly for want of a better description. Colour of oil is ok, and I`ve tried to pour out the contents to see if I can find this lump, but its not there. Did I dream this or was it a thing?
I`m now going to refill it with cheap crappy oil and run a full engine flush though it just in case and then strip out all the strainers, filters and pressure relief valve.
Dave
Is your engine venting OK?
Mine vents to a catch pot and I get a surprising amount of water and mayonnaise in it
As far as I know it vents ok -
No water or mayonnaise though - Actually seems really healthy :-\
Tried to find CSP relief valves, in stock at a decent price from CSP Germany but need to buy £200 worth to get them shipped to UK Thanks to my favourite MP for that.
All uk sites I could find with them are out of stock, many at over double the CSP price.
Most available ones are listed as "High. Performance" so probably made of butter with stronger springs.
Got some another way from Kingfishet.
Just for information:
My engine is a 1600 VW Heritage unit that I purchased in December 2012. When I changed the my relief valves several years ago I fitted the CSP items show below
(https://i.postimg.cc/43NY8yc2/CSP-Oil-Relief-Valves-1970-on.jpg) (https://postimages.org/)
The strange thing is when the engine had been built by VW Heritage the front valve was the earlier type show below
(https://i.postimg.cc/rFV2R4Lk/CSP-Oil-Relief-Valve-pre-1970.jpg) (https://postimages.org/)
Anyway the CSP items have worked perfectly since fitting so no problems.
I wonder why they fitted the earlier type control valve when it was built?
Probably what they had on the shelf Chris
Water/mayonaise........ This was to be found on most vehicles of yesteryear. It is a mixture of water vapour and oil mist. The most common place it was found was on the underside of the oil cap, metal ones especially so.
The most significant thing this mayonaise sludge indicated was that the engine was simply never run up to "full temperature" frequently enough and for sufficient length of time to boil water from the oil sump. The oil/water mist condensed onto the underside of the oil cap as well as within the rocker cover/s.
On a type one engine with a single carb, for example", within the oil filer section, just before the breather pipe connection, was a wire mesh "mist separator". On other, water cooled engines this mesh was within a container. The mesh was to do as it says and "strip" most of the oil from the mist and drop it back into the engine the remainder going into the carb air passage and back to cylinders 1 & 2 to be burnt during the combustion strokes. If you have the mesh fitted, and you should, ensure you have, it can get clogged up and become useless if covered in the sludge.
There is an important moral to this story.... Run your engine up to full temperature - preferably on the road rather than just in the garage over winter.
Why you may ask..... Well you do not want any more water in your oil than possible,
Mine gets plenty hot enough.
Has the grooved pulley so pumps air in which then extracts to a catchpole to condense, that's where the water and some mayo collects.
Engine itself is clean of mayo, none on oil filler or in rocker covers.
The exposed engine in a buggy means breather hoses and alike suffer from wind chill so rarely get hot enough in cool weather an oil temp sender in the sump plug hole will only register a temp when stationary because of the air flow.
My take on this is that VW designed it to pump air in to slightly pressurise the case which then vents to atmosphere via the filler neck breather.
By definition it's a occasionally damp in th UK so trace moisture will go in, a bit more if you drive through floods or ford's, as if ;D
I fitted breathers to the rocker covers, as well as a sump extension, as on tight fast roundabouts I had oil pressure drop. My fault as I might have been going a little faster and tighter than in the Beetle design spec. On top of that once it had happened it could take a long while to drain back, venting solved the latter problem by breaking the vacuum, sump extension the former. It was either that or buy a flat cap, trilby and a pipe and be sensible. :o
My breathers pipes from rockers and oil filler go to a condensation box on the firewall, this drains to a catchpot with a level indicator, drain plug and a filter on top to atmosphere.
Every few hundred mikes I get half a cup of oily water and a spoon of mayo drain out.
So I think it proves its working well as there will always be trace moisture in the case when you switch off which will condense on the oily metal and make a little mayo. I get none in the oil filler and a tiny bit in the top corner of the rocker covers, can barely see it.
Over engineered, yes but that's just the way I like it.
Finally started on this and went to drain the oil, realised it's a bigger job than I thought as extended sump has to come off.
Quote from: Doon L001 on February 16, 2026, 10:54:55 AMFinally started on this and went to drain the oil, realised it's a bigger job than I thought as extended sump has to come off.
Strange? The regular sump plate and strainer should be fitted to the bottom of the extended sump so no harder or messier than usual.
As usual you're right David
The plugs are outside of where the extended sump sits, just hadn't looked properly. I'll blame it on poor light in the garage.
Next opportunity is Thursday when Lynn's at work and her car isn't in the garage, then I'll have room to jack it up and get at it.
May have found root cause, magnet is missing from the sump plug
With luck the magnet is resting in the sump oil still collecting shreds of metal. If you replace the magnet then the new one might 'catch' the detached one as if it slides about ?
I'll take the plate off and give it a sweep with a magnet on a stick.
Take the pump cover off and check in there.
If I can't find it have to try and poke through the first set of galleries.
Progress, if you can call it that, so far.
Couldn't shift the relief valve covers, they'll have to wait until I get the back end in the air. Might find a bit of steel that fits and weld it to an old socket.
Got the pump cover off, no sign of damage or foreign objects in there.
Blew the line to the filter through.
To do that I had to take the exhaust headers to the rear cylinders off and the pulley, now struggling to get the pulley back on. Goes so far but not the last few mm. Beaten by the cold so.more tomorrow.
The Bottom pulleys stick out about a quarter of an inch from the crankshaft! Does it line up with the alternator pulley?
Quote from: farmer rob on February 18, 2026, 04:23:46 PMThe Bottom pulleys stick out about a quarter of an inch from the crankshaft! Does it line up with the alternator pulley?
No, it needs to go in a little more. It's an ali aftermarket mst one.
Turns ok so not binding in the hole more likely on the shift. Didn't take the woodruff key out as pretty sure I loctited that in when I fitted it so it wouldn't tikt when refitting. It's been well cleaned as well.
Well your magnet should not be able to get through the gauze filter! If you have a steel sump plate, it will be stuck on there or the pick up tube,
That's what I thought. May even have come out with the previous oil change. Beats me how a magnet can fall out of a steel plug in the first place
Quote from: Doon L001 on February 18, 2026, 04:06:05 PMCouldn't shift the relief valve covers, they'll have to wait until I get the back end in the air. Might find a bit of steel that fits and weld it to an old socket.
Having the same issue on mine - have a google for "APEX HTS BITS" as they look really promising for solving this problem
(https://eumro.co.uk/wp-content/uploads/2022/09/hts-7-apex-1-2-hi-torque-7-square-drive-insert-bits.jpg)
Just ordered a set from the States - If you are still struggling in a few weeks when they arrive, happy to send them over for a play
£7 on Ebay, number one size guess you've already worked out what size is needed, care to share? ;-)(-;
I have been giving this some more thought And with your previous symptoms, It sounds like the magnet is actually stuck inside the pick-up tube!
So at tick-over, enough oil can still get through to the pump to give you the correct oil pressure. But as you rev it up, the pump gets a limited supply of oil so can not give good pressure.
So I don't think it is an oil relief valve problem. So leave them for now! My plan of attack would be to take the oil pump cover off and remove the gears. Then you will need to get a choice of electric wire, until you can feed one of those through the pump and out of the sump. You could then pull some string through to the bottom and then tie a small piece of cloth to the string and pull it through to the bottom, hopefully with the magnet.
That's a good idea Rob, I'll have a crack at that tomorrow
Done some research to try to identify what bit fits what slot, unfortunately all I've found so far is that the number relates to the bolt size, not a lot of use when we need to match it to a plug.
More research tomorrow
Dave
I have a pair of HEX drive spring retaining plugs if you want them.
Should make refitting easier.
(https://i.postimg.cc/wBvwsrsp/Whats-App-Image-2026-02-18-at-22-38-05.jpg) (https://postimages.org/)
Thanks Chris, I've PMd you
Quote from: Doon L001 on February 18, 2026, 06:53:57 PM£7 on Ebay, number one size guess you've already worked out what size is needed, care to share? ;-)(-;
No idea on my T25 lump, hence ordering a whole set of them
Haven't got to them yet but reckon a pound coin would be a decent fit, cheap tool if it does the job and that star Chris will mean I only need the tool.once.
Sent First Class from my local post office this afternoon. Hope they make refitting easier.
Quote from: Doon L004 on February 19, 2026, 02:16:36 PMSent First Class from my local post office this afternoon. Hope they make refitting easier.
You're a hero
PM me what i owe you
Progress is slow, had a rough winter so being wary of too long in the cold.
Out of interest Chris I got a new set of valves and one of them has the cutout that defined it a single port version.
Quote from: Doon L001 on February 19, 2026, 09:14:36 PMOut of interest Chris I got a new set of valves and one of them has the cut out that defined it a single port version.
I don't understand what the cut out does. Below are valves that came out of my 2012 VW Heritage 1600 engine
(https://i.postimg.cc/9MH82VCy/Whats-App-Image-2026-02-19-at-22-22-13.jpg) (https://postimages.org/)
I replaced them a couple of years ago with the CSP set which solved my problem of over pressure they have no cut out.
Cold start up and 3000 rpm = 45 psi, Hot running at 3000 rpm = 45 psi, Hot tick over = 15 psi
(https://i.postimg.cc/RVYT99TP/CSP-Oil-Relief-Valves-1970-on.jpg) (https://postimages.org/)
Maybe one of the engine builders on here can explain the cut out?
The plugs have just arrived Chris, thanks very much
Well some progress, maybe.
Extended sump off, pick up extension was slightly loose but as thats under oil wouldn't have made any difference.
Failed to get anything through the gallery, too many tight turns.
Got relief valve plugs loose with a hammer and drift, rearmost one out but at the moment can't get the plunger to come out, bit of thought needed to work out how to grip it from inside and, of course, my magnet on a stick I used yesterday is nowhere to be found today :o
Oh the joys of buggy ownership
I screw thread taps into the plungers to get them out when they are stuck but this is on old engines that have sat for some time. On a running engine, they usually drop out
That's what I expected they should drop
I'll find my magnet, then try 2 long screwdrivers
Trap is a last resort
As soon as the tap starts to bite, the plunger will turn and then you can push and pull on it to see if the plunger does move nicely
I hadn't thought that through, not tapping a thread just enough to grip.
Thanks Rob, may not get to try it until Thursday
I'll let you know
Stuck/sticking valves could be your problem at least you found a defective part.
That's what I'm hoping Keith, it's pretty well stuck
Well guess ive found the fault
Ram an m10 tap into the hollow in the piston, the one at the pulley end, and it wouldn't budget.
Couldn't really grip the tap as the end was inside the recession but the piston won't even turn. Seem to remember them almost falling out when I did this on my old engine.
Will try and find a long m10 bolt and see if I can tap enough thread to get a hold of it.
Oil back in run it up to get hot then try removing the plunger once the case has expanded.
Before I do that I'll stick a heat gun on the gallery where the oil from the filter returns,
I'll leave the spring out and oil pressure might push it down.
Well progress today.
Heated the case until I couldn't touch it. Got a cuppa and came back in the garage and heard a thump as the piston dropped out.
Cleaned the old pistons and springs as the replacements I bought are so called "performance " parts. The springs are much stronger.
In the process of reassembly now.
Slowly going back together, done some other work while it's in bits.
Improved the oil pickup from the extended sump.
Taken the bottom cover screws out a couple of turns as nuts only had a couple of turns before.
New oil and filter (again)
Refitted woodruff key and pulley went on nice and easy.
Going to do tappets, clean carbs and swap out dizzy cap and leads while it inbthe air and ive got the silencers dropped
Delighted it's resolving but sounds like there has been mission creep and summers here so get it back together very soon !
Quote from: Hugh on March 20, 2026, 07:42:52 PMDelighted it's resolving but sounds like there has been mission creep and summers here so get it back together very soon !
Only jobs that needed doing, not taking it to bits twice if I don't need victory.
I get limited time to work on it when Lynn's at work
Taken the bottom cover screws out a couple of turns as nuts only had a couple of turns before.
If this refers to the studs that you secure the oil drain/mesh filter plate then it`s one thing that over the decades has driven me crazy. The number of times that I have been asked to "fix things" is beyond counting. So often the plate is put back on and secured with nyloc nuts. Next time the plate needs to come off the nyloc is grabbing tight to the stud and the stud unscrews, That`s it then...... one or more of the studs will simply just screw itself all the way back in even with a normal nut on. You cannot use loctite on the stud thread because it`s impossible to clean oil out of the threads. :'( :'( As a quick fix I just lock a nut down the bit of stud extending inside the case. There is a permanent fix. Cannot recall what they are called technically but it`s a threaded stud with a diagonal slash along the thread length. This locks the stud in position exactly where you want it..
They do a saver stud 8mm one end and 6 the other so you drilll and tap the case from the 8mm.
Yes Paul, they're the studs.
Problem was I have an ali cover which is thicker than the original steel one, nice chrome domed nuts but they only went on about 3 turns but sort of OK as there's no real strain on them.
Studs wound out a bit and all bar one nice and tight, loctite will give it enough sticktion
Nuts on about 9 turns now so much happier.
Not enough thread on the inside if tge sump for a nut and they're already longer than standard studs
Yep... The alloy finned sump cover with the temp sensor needs a few extra thread turns to allow a nut and lock washer to fit properly. I keep some 6mm longer length studs cut from bolts handy to use. Also have a thin walled socket to get into the cover recesses to nip the nuts up.
Good news hopefully
Took both relief valves out again and fitted the so called performance set after giving the guides a good clean.
Started and oil pressure is stable at 40 psi so progress.
Do a test run over the weekend and see what happens when it warms up.
Had to fit this round gardening, building shelves and decorating so taken far too.long.
Those hex plugs Chris sent me are really good, thanks again. ;-)(-;
For info, you can get the valves out with the extended sump fitted and can get the pulley end back in.
Flywheel end is another issue as you can't get a straight line to start the thread against the spring pressure.
Ive got some alien keys without ends, which got it out, but not enough room to hold it straight and rounded end too grippy with tge soring pressure.
In the end I cramped 2 nuts onto a 10mm head bolt and put a ratchet ring spanner on it, that let me get it started
Thanks for all the advice on this
. Dave
Just drove out of the garage pressure all over the place.
Before I take tge engine out I'll take the gauge sender out and check the channel to that. Slightly odd gauge drops to zero but light doesn't come on.
Could be bad connection somewhere or screw a capillary gauge straight into the sender hole for a accurate reading.
Quote from: snoopy on April 05, 2026, 05:00:38 PMCould be bad connection somewhere or screw a capillary gauge straight into the sender hole for a accurate reading.
Yes I'll check all that.
Still worried about that missing magnet but every chance it's in the old oil or filters
Yep..... first port of call a 2nd pressure gauge just as a check.(Capillary version). I have lost count of how many "classic cars" have been brought to me with oil pressure showing above 50 psi on gauge at start up dropping to just above zero when hot and going up to indicated 20 psi at hot idle. Panic sets in but it`s an old tired gauge that,s the issue in most cases, Rarely a collapsed capillary tube of duff sender. Ancient ammeters have minds of there own as well ;D Modern oil pressure gauges/senders are of a quality/reliability dependent upon where they are made. To be realistic however all you need to know is that the gauge is giving an indication that you have an oil pressure. Classic cars still have an "oil light" on the dash as well as a pressure gauge. It all comes under the heading of the "joys of motoring". How I ever got involved in this stuff all those decades ago enjoying every minute I don`t know" . Seems now all I do is accompanied by moans and groans from muscles joints and it may be my imagination but I think there really is such a thing as "brain ache". Glutton for punishment am I as am just about to go out with a crying shoulder joint once again (Triumph Stag this morning not a Beach Buggy).... ;D ;D
Stag waiting patiently for me to open door & lift bonnet in the sunshine....
One of the most attractive 70`s cars a Stag is. This one is a rare thing indeed. Other than a repaint, somewhere in the past, it`s all original even to the 54 year old carpets. Mind you carpets this old are threadbare in places and have that "old relic" moisty smell. All part of classic ownership.
Oil pressures fine just an old gauge doing it`s best in it`s old age. Just like me ;D ;D
Most importantly the engine thrust washers are sound and secure. Has twin Stromberg 175 CD2 carbs that to no surprise are way out of synch etc. (Another job to do). Strange how maligned the Stromberg constant depression carbs are. They do the job brilliantly as long as they are in decent condition and set up correct.
Another moan but all part of old age..... How on earth can Boots charge you £22 for one tube of Voltarol ?????
(https://i.postimg.cc/k5dMKJCr/s1.jpg) (https://postimg.cc/3knHHHW9)
(https://i.postimg.cc/90SCMVbJ/s2.jpg) (https://postimg.cc/7JgpsFp2)
Well the saga continues.
Took the oil pressure sender off and gave it a good spray with parts cleaner, thought that had fixed it.
Guage reading and pressure increased when revved,, happy days.
Took it for a drive, filled up with fuel and came up to temperature
About 7 or 8 miles, all good
In the evening off to a local meet, another 8 Mike run
Stayed for an hour or so and headed home, still some heat in tge engine and got to 80 but then just kept going so now overheating.
As oil is a big part of the cooling if flow is poor tonearm of the engine thats what I guess would happen, so back to the drawing board
One more stupid question in case I'm going mad
Relief valves
Long spring at the pulley end, short spring flywheel end, yes?
Doon..... run engine for 20 minutes. Use a infra red temp reader on each head see what you get. A seriously overheating engine will start to bind and you will hear this as revs drop.
Dont have a temp reader but drive last night for welll over 20 minutes and performance was fine just temp climbing.
Weird.... Oil is critical in heat transfer in any engine. I am not understanding why you have a constantly climbing temperature when the buggy is in motion.I would only expect this with a duff cooling fan or slipping belt or knackered oil pump or defective valve not allowing oil up through the gallery to the oil cooler and back or gallery blockage. But with oil not going thro` the cooler I would expect a very rapid oil temp rise up to engine running issues
Paul
Can you confirm
Relief valves
Long spring at the pulley end, short spring flywheel end, yes?
That's how ive fitted them, clutching at straws here.
Hi Dave, yes, long spring at the pulley end and short spring at the flywheel end. Right, oil pressure and cooling!!! When you start an engine, the oil is cold and thick and the pressure is high. So the first oil relief valve opens and sends the oil down an oil passageway to by-pass the oil cooler! As the oil warms, the pressure drops, the oil relief valve then closes and lets the oil through the cooler.
So if you have too much oil pressure from HD oil relief valves springs, too larger oil pump or too thick engine oil, your engine can run hot because the oil is by-passing the oil cooler when it is up to normal engine temperature. It is the oil relief valve on the flywheel end which generally governs the over all oil pressure. So ideally, if you are running a standard oil cooler, you shouldn't go above a 26mm oil pump! Some of the after market, combined oil pump/filter units are now coming with 32mm oil pumps when advertised as 30mm. So these can cause big over heating problems unless you use thinner oils.
People building performance engines often get over heating problems because they think they need big oil pumps but they don't, unless they are running external oil coolers
Hope this helps
Thanks Rob, thats interesting.
No idea what pump is on there, the engine was built by Dan Simpson who i believe is no longer with us.
It has an external filter and an oil cooler withb an 80* thermostat
Ive refitted the original valves which have standard springs rather than the :performance " ones which were all I could get.
Ill take it for a run when I get a chance but not too far.
I was taking it to Rustival Saturday but going in my mates Golf now.
My concern is that missing sump plug magnet, if that's lodged in a gallery. How a magnet drops out of a steel plug i don't know and there's negligible flow over the plug to pick it up so I was hoping it fell out in the oil tray when I drained it and went with the old oil.
If all else fails it will have to come to bits and inspect all the galleries
Want the job?
If your magnet has come adrift in the motor it should stick to the pick up pipe as that is the first metal it passes before the cast pump or steel gears and if it got there there would be serious damage as they try to crush it. You could put a bore scope up the tube or remove the pump cover if not already done.
That's acrelief keith. Ive had the pump apart and pushed a magnet up the intake pipe
getting hotter and hotter on a run you could try a digital thermometer to see hot spots you could have retarded timing or a slightly weak mixture at a higher rev range causing the heat, is the standard cooler clear of debris the fan sucks in and are the cooling flaps in the open position.
If you are running a standard Fan housing the flaps are open by default as long as they are free to move. If you have the original arm coupling this should have it`s spring in place and the daft coupler to rod clips free to move with the small rod like. connections
Go back to basics...... (See if this makes sense to you).
This has always been my first "port of call" when I have suspected an oil flow issue or even a stuck exhaust valve...
Get two containers that you can place under each cylinder head/rocker cover area. Thoroughly warm up the engine so that you know, that in theory, the oil is hot enough to go through the oil cooler route. With the engine hot remove each rocker cover so that you can see both sides easily. Start the engine and let it idle. You will not get covered in oil.... maybe just a flicked bit from the rockers so have your old clothes on. Oil makes it`s last travel up the pushrods out of the little hole on the domed end. Covers vale springs rocker arms etc before falling to the lower part of head rim. Oil goes back home to the sump down the pushrod tubes. Firstly look at the rockers and springs and you should see a decent flow from the [pushrod area back down the tubes. (You will get a bit of overflow at the lower edge of the cylinder head into the containers each side but there is plenty of time to take a good look). (Bear in mind that I have never seen both sides with exactly the same oil flow. One is always a little more than the other).
As I see it when I look at things in this manner if I have a decent flow of all from all pushrod tube tops and oil going back down the pushrod tubes then the oil flow is un-interrupted through the oil galleries. If there is any sign of "no flow" from one or more pushrods then there is a blockage. Most often, but not always, in the pushrod. If there is no oil then that`s bad news but is very unlikely.
I would then argue that if the engine temp` continues to rise past a normal operating temperature then either a restricted flow or none at all is going through the oil cooler. This happens. It can be crap in the oilway to/from cooler. Can be dismantling cooler seals. Can be a cooler issue itself but if original VW no matter how old it`s rare.
A few words there but I am describing a simple thing that only takes 30 minutes at the most and it gives you an idea of wether all is well or to save much time second guessing it`s out with the engine. One other thing that I consider critical is whatever is used to determine temperature is climbing way past what it should needs to be accurate. What, in my opinion, is not is aftermarket sump sensors and gauges. Take a look at a Smiths gauge cost compared to an "ebay" chinese special. I am not being critical here but I fitted one of those aftermarket finned alloy sump attachments with the brass temp` sensor and an ebay gauge. Had these bits on a week during a summer and took them straight back off. A lot of money down the pan if you are looking for accuracy. Used a pan to heat up water alongside a known lab quality mercury thermometer and the results were useless.
Anyway Doon. I hope this quick check may help you decide if it`s engine out or not. At least it`s keeping you occupied ;-)up
Here is what my VW stuff says is typical temperature range in a type 1 engine within it`s Beetle home... 180 - 220 degrees F 82 - 104 degrees C
Thanks both
Never thought of that rocker covers trick, great tip.
Full engine tune is never a bad thing Keith
It all started after an oil change.
Just an oil change...... I think the answer lies there. Many, many years ago I was told that the "simplest answer is usually the correct one"....
I have seen so many oil flow issues since the introduction of "silicone mastic".... After it has been in oil for a while bits hanging about around "sealed" areas become jelly like, come away and I have seen large bits get straight through the mesh oil strainer. I think there is a good chance that something has got into an oil gallery. A potentially easy fix but you will know that will entail a strip down and crankcase galleries made accessible to an airline. If you have access to Trike even better. (No I didn`t mention that chemical it was a typo error honest ;D )
Builder didn't use solicone mastic, neither do I. So unlikely to be that.
Also have an external filter, I know some bypasses, but filter changed as well.
Even if that were the case id expect traces to be visible on the mesh.
I'm using Classis oil, always have.
Odd Doon.... I will be really interested to learn what the issue turns out to be.
Quote from: Paul1953 on April 16, 2026, 07:57:05 AMOdd Doon.... I will be really interested to learn what the issue turns out to be.
I'll get to the bottom of it one day, just very limited opportunities and space to work on it
Fitted a cheap mechanical pressure guage instead of the warning light and it mirrors my electric guage albeit with a delay probably due to air in the pipe, so only bit of good news is my guage and sender are OK.
Took rocker covers off and there's a dribble of oil reaching the rockers so some is getting through but pressure on guage all over the place.
Looks like it's engine out.
Doon...... Having used the rocker cover off check many times now, and having seen a pro re-builder do the same, the flow should be far more than a dribble. I would take the engine out and strip it down. There is a good chance of one or more exhaust valves sticking open if the cylinder head/heads overheat.
My guess is there is some crap in the oilways which can also be in the pushrod tube but I have never seen all tubes blocked. It`s more usual in just one or two.
Re- capillary tube to an oil pressure gauge.... I have lost count of how many classic/vintage cars I have seen where these tubes, when clear material is used appear to have air in them,
Don`t forget to pressure up the oil cooler with an airline just to check it hasn`t collapsed within. I don`t think it`s coincidence that the issue followed an oil change.
Bit of old school stuff from me - an ancient old schooler with no engineering training just decades of direct hands on experience. (For you on the forum knew to engine mechanicals)
Take a look at photos. 54 year old engine. 54 year old capillary tube and 54 year old Smiths oil pressure gauge... Don`t overthink things. (easy to say I know)....
The photo of the dash gauges is at start up from cold hence engine at "fast idle" due to choke cable positioning the 2 Stromberg carbs at fast idle position. (1500 rpm exactly where it should be). The thing to note is a stable oil pressure indication... not the actual oil pressure. Then take a look at the other photo showing the capillary tube itself. The dark green sections of tubing is the oil the other is air. You could try and disconnect and get air out but it wouldn`t take long for it to re-appear.
The important facts to gleen from such a scenario is a stable positive oil pressure. As an engine heats up, and especially after a long hot run, this pressure will very probably drop away in most cases but return when back to idling and cooling in effect. That`s all you need to know. The actual gauge reading is nominal at best unless you have a very expensive set up.
(https://i.postimg.cc/Hn66Lxb7/2.jpg) (https://postimg.cc/D4brj7j2)
(https://i.postimg.cc/JzDp1R07/1.jpg) (https://postimg.cc/3khX152z)
Dont worry Paul,, I don't really pay much attention to the numbers on guages just to change and stability - except with Speedo and Rev counter
Hope you get sorted soon. I for one really do appreciate how restrictive space can be. I do everything from my buggy build to all other stuff in a tiny brick garage and minimalistic shed. Having one arm almost completely out of action since January has been a real eye opener. I am right handed and what a thing it is to realise how much your left arm/hand does in conjunction with the right. I am in awe of folks managing with one arm or one hand. ;-)(-;
Ancillaries off and oil out, engine out next week.
Will pressure wash it before dismantle after blocking all the holes then the work starts.
Never dismantled a Beetle engine so Haynes manual at the ready.
Dont have access to an airline, have bike pumps that can store 200psi and let it go in one burst. Will try that with an old car valvev to get a seal on the oilways.
Did think of using the pressure washer on oil ways then drying the case in the oven- don't tell Lynn. Any thoughts?
Washing the case will be fine the water will evaporate.
Quote from: snoopy on April 25, 2026, 08:14:43 PMWashing the case will be fine the water will evaporate.
Cheers Keith'
That's what I was thinking
You will enjoy dismantling and re-assembling the engine.....
Made progress
Was going to add a pic of engine on stand but won't add images for some reason.
Will start major surgery tomorrow.
Fan housing and alternator off then pressure wash the dirt off after a soak in Gunk
Use a wax based sealant sparingly. Blue Hylomar or WellSeal. Not silicone under any circumstance. (Wax based sealants ensure any excess within case can dissolve and not cause a blockage).
Plenty of engine oil on moving parts during re-assembly and of course the utmost cleanliness during re-assemble.
Absolutely Paul.
Started dismantling and bottled out before splitting the case so going to Farmer Rob so a grown up can do it.
I haven't really got the space or a clean enough work area.
A bit off putting when the Haynes manual says how different and complex it is.
Done old non crossbow Firds before and they're a piece of cake mounted on an engine stand, can't do that if you have to split the case.
Wow.. 100% baffled.... How can anyone like Haynes state the engine is complex. It could not be more basic.
Quote from: Paul1953 on May 14, 2026, 02:22:48 PMWow.. 100% baffled.... How can anyone like Haynes state the engine is complex. It could not be more basic.
👍👍👍old school motors are simple machines unlike the modern variable vale timing engines and stuff around these days.
Best go with Rob and watch a strip down of the motor the only awkward reassembly bits are the cam followers dropping out as you lower the top case on but a bit of grease will hold them in if you do not have the spring clips.
Quote from: Paul1953 on May 14, 2026, 02:22:48 PMWow.. 100% baffled.... How can anyone like Haynes state the engine is complex. It could not be more basic.
They meant more complex to dismantle i think. Old Ford engines stayed on the engine stand.
Head off, turn engine over, sump off, remove internals.
Can't do that on a beetle
Well Rob has checked it out and oil flowing nicely now. Only thing he found was a missing O ring on the oil pump.
Only bit I didn't send him was the external oil cooler so will run it for a while without and refit when I change out the flushing oil and see what happens
I just had similar on another motor - split o-ring on the intake side letting a tiny amount of air into the pump, stopped it building any pressure.
Had the engine in the car for a few miles with the flushing oil in.
Fixed a few minor oil seeps where the pipework had been disturbed refitting, nice and smokey where it got on the exhaust wrap.
Got an mot and going to Rustival tomorrow so at the start of the week decided to put proper oil in.
Goes like stink now Robs breathed his magic on the cstbs
Refitted the external oil cooler and the only filter I had that came off a while ago after a few miles
Oil pressure all over the place.
Removed cooler, still the same.
Picked up a Golf filter and that cured it, so looks like ive got a filter with failed internals, probably acting like a bellows.
Anyway good to go for Saturday and will fit the cooler again next week
Old filter is draining then I'll cut it open and have a peep inside.
Good news you are sorted oil filters can be a bit more involved than just a filter element.
https://www.fram.com/vehicle-maintenance-center/post/how-oil-filters-work
Quote from: snoopy on September 25, 2026, 09:46:42 PMGood news you are sorted oil filters can be a bit more involved than just a filter element.
https://www.fram.com/vehicle-maintenance-center/post/how-oil-filters-work
I'm always uncomfortable when a fault just goes away without finding the root cause.
Bit of a pain it was out of use all summer over something so simple, but every cloud, it's so much more responsive and quicker with the carbs done.