Hi al, just trying to reduce the squirt on my accelerator pump,i have loosened the 8mm nut but cant get the slotted arm to move, do i need to loosen the 12 mm nuts on either end of the butterfly shaft that seems to go right through the carb too. Cant remember from last time i did it . Thank you 👍
Sorted it, was just stiff, adjustedmore in the middle now so test later 👍
Hi all, sooo. I went for a test to see if any better with pump adjusted , didnt start as well from cold but i think to be fair the choke had unset itself from the highest step to a lower one so nearly stalled and i gave it a few blips which mean5 id was lumpy and smoking as a bit rich , then it evened out as it warmed up and i went wenty miles and it performed well in traffic, no hesitation and plenty of power, and started better when warm . I got home and i had read that I should check if my choke butterfly is dead upright when hot , i removed air filter and looked inside with a mirror , it is not quite completely upright, but i also noticed it was dripping petrol into the bottom of carb, i tapped carb body in case needle walve was sticin but still doing it. Any suggestions .? Also i thought to get the choke butterfly upright i needed to loosen choke but didnt seem to want to make it much different , so put it back as i thought but now i think i may have mucked up my choke settings, but my choke hasnt reLly been setting itself properly since the last time i tweeked it. And suggestions on dripping fuel and easiest way to set ckoke again. Many thanks 👍
It is best to check the choke when cold. Slacken the three screws, hold the throttle lever away from the step mechanism and then turn the choke mechanism until the choke butterfly closes. then retighten the three screws. Make sure the butterfly shuts easily, if not give it some lube. There is a little diaphragm, so when you rev it a bit with the choke on; the butterfly should open slightly and then return. If it does not do this, then the diaphragm could have gone hard or cracked or the shaft that moves it may want a bit of lube. this diaphragm is behind a little plate with three screws in it.
When you have checked all this, check to see if the butterfly is fully open after about 3-4 mins. Do not turn the ignition on and not start it, as this starts knocking the choke off before you are ready to start it ;-)up
Rob
dripping fuel where from it could be a worn/dirty needle valve, incorrect float level, pump over pressuring and a faulty gasket or carb faces deformed and not sealing.
Quote from: farmer rob on May 14, 2018, 05:51:33 PM
It is best to check the choke when cold. Slacken the three screws, hold the throttle lever away from the step mechanism and then turn the choke mechanism until the choke butterfly closes. then retighten the three screws. Make sure the butterfly shuts easily, if not give it some lube. There is a little diaphragm, so when you rev it a bit with the choke on; the butterfly should open slightly and then return. If it does not do this, then the diaphragm could have gone hard or cracked or the shaft that moves it may want a bit of lube. this diaphragm is behind a little plate with three screws in it.
When you have checked all this, check to see if the butterfly is fully open after about 3-4 mins. Do not turn the ignition on and not start it, as this starts knocking the choke off before you are ready to start it ;-)up
.thanks rob will re set it again👍
Rob
Quote from: snoopy on May 14, 2018, 09:26:58 PM
dripping fuel where from it could be a worn/dirty needle valve, incorrect float level, pump over pressuring and a faulty gasket or carb faces deformed and not sealing.
thanks snoopy, i have never checked float level as was a bit loathe to disturb things, the fuel is dripping ftom one of the brass tubes in the carb or the curved one, is that theaccelerator pump? Is it easy to check level of float👍
Easy to check, top off carb then upsdide down and measure from float to the sealing surface or level of fuel in chamber to top of body. Measurement depends on the carb so a look at a manual or online will find the correct one. Floats can leak and fuel inside so give it a shake as that causes them to sink lower and cause flooding.
Quote from: mad4slalom on May 14, 2018, 10:45:43 PM
Quote from: snoopy on May 14, 2018, 09:26:58 PM
dripping fuel where from it could be a worn/dirty needle valve, incorrect float level, pump over pressuring and a faulty gasket or carb faces deformed and not sealing.
thanks snoopy, i have never checked float level as was a bit loathe to disturb things, the fuel is dripping ftom one of the brass tubes in the carb or the curved one, is that theaccelerator pump? Is it easy to check level of float👍
Used to happen on my twin carbs as engine heat after a run travelling up manifolds was enough to boil fuel in the float chambers. Thicker gasket solved it.
Quote from: Doon L001 on May 15, 2018, 08:07:37 AM
Quote from: mad4slalom on May 14, 2018, 10:45:43 PM
Quote from: snoopy on May 14, 2018, 09:26:58 PM
dripping fuel where from it could be a worn/dirty needle valve, incorrect float level, pump over pressuring and a faulty gasket or carb faces deformed and not sealing.
thanks snoopy, i have never checked float level as was a bit loathe to disturb things, the fuel is dripping ftom one of the brass tubes in the carb or the curved one, is that theaccelerator pump? Is it easy to check level of float👍
Used to happen on my twin carbs as engine heat after a run travelling up manifolds was enough to boil fuel in the float chambers. Thicker gasket solved it.
will check that , thanks , would the carb bowl be hot to the touch tho if fuel boiling?
Quote from: snoopy on May 15, 2018, 07:57:59 AM
Easy to check, top off carb then upsdide down and measure from float to the sealing surface or level of fuel in chamber to top of body. Measurement depends on the carb so a look at a manual or online will find the correct one. Floats can leak and fuel inside so give it a shake as that causes them to sink lower and cause flooding.
another job for the weekend then, thanks 👍
Quote from: Doon L001 on May 15, 2018, 08:07:37 AM
Quote from: mad4slalom on May 14, 2018, 10:45:43 PM
Quote from: snoopy on May 14, 2018, 09:26:58 PM
dripping fuel where from it could be a worn/dirty needle valve, incorrect float level, pump over pressuring and a faulty gasket or carb faces deformed and not sealing.
thanks snoopy, i have never checked float level as was a bit loathe to disturb things, the fuel is dripping ftom one of the brass tubes in the carb or the curved one, is that theaccelerator pump? Is it easy to check level of float👍
Used to happen on my twin carbs as engine heat after a run travelling up manifolds was enough to boil fuel in the float chambers. Thicker gasket solved it.
. Do you mean a thicker gasket between bottom and top of carb , i dont think i have a gasket in there at all or i may be thinking no gasket between carb base and manifold 🤔
Quote from: mad4slalom on May 15, 2018, 09:06:57 AM
Quote from: Doon L001 on May 15, 2018, 08:07:37 AM
Quote from: mad4slalom on May 14, 2018, 10:45:43 PM
Quote from: snoopy on May 14, 2018, 09:26:58 PM
dripping fuel where from it could be a worn/dirty needle valve, incorrect float level, pump over pressuring and a faulty gasket or carb faces deformed and not sealing.
thanks snoopy, i have never checked float level as was a bit loathe to disturb things, the fuel is dripping ftom one of the brass tubes in the carb or the curved one, is that theaccelerator pump? Is it easy to check level of float👍
Used to happen on my twin carbs as engine heat after a run travelling up manifolds was enough to boil fuel in the float chambers. Thicker gasket solved it.
. Do you mean a thicker gasket between bottom and top of carb , i dont think i have a gasket in there at all or i may be thinking no gasket between carb base and manifold 🤔
There are specialist gaskets available to prevent the fuel from boiling and evaporating when stopped - have a look at Eurocarb website maybe
As said they do thick plastic sort of spacers to go betwen the heads and manifold and carbs and manifolds. I went for the diy option of a few paper gaskets as insulation top and bottom.
I noticed the boiling when I could hear a fizzing noise after switching the engine off. Thicker gasket between carb and manifold as a bit of heat in the manifold is a good thing.
Don't go too thick as carbs may foul on the fan housing. Mine are about 5mm I think
Phenolic gaskets are the the proper job. I think they're about 10mm thick. Got them between carb and manifold for twin 40s on my type 4 2ltr. I've also got them for manifold to heads but haven't decided whether to fit them yet.