i need help with my flat-4

hello everybody, i began building a buggy from a VW Variant, before taking it appart the engine was running exelently however the body was so rusted up it was not worth keeping it. i have finally gotten the engine in place and connected everything up and i recently started the engine after about 18 months without running is started pretty much immediatly however after about five minutes of runnung the engine would try turning off. you have to pump the gas vigorously to keep it running just. im not much of a mecanic but i think that it is to do with lack of petrol thus by pumping it the injection cuircuit in the carburettor keeps the engine running... any help would be greatly apretiated!! P.S: i had to change the coil for a second hand one.. dont know if that has something to do with it. i also checked the spark plugs and they were quite black with carbon residue. thank you again Stefan

Reply to
stefanbryant
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hello everybody, i began building a buggy from a VW Variant, before taking it appart the engine was running exelently however the body was so rusted up it was not worth keeping it. i have finally gotten the engine in place and connected everything up and i recently started the engine after about 18 months without running is started pretty much immediatly however after about five minutes of runnung the engine would try turning off. you have to pump the gas vigorously to keep it running just. im not much of a mecanic but i think that it is to do with lack of petrol thus by pumping it the injection cuircuit in the carburettor keeps the engine running... any help would be greatly apretiated!! P.S: i had to change the coil for a second hand one.. dont know if that has something to do with it. i also checked the spark plugs and they were quite black with carbon residue. thank you again Stefan

Reply to
stefanbryant

SWAG that the float-valve in your carburettor is stuck. That or the automatic choke (which is electric in most cases.... did you re-connect the choke wire?).

Try disabling the choke and try flushing the carburettor with cleaner.

Last SWAG... do you have an electric idle cut-off? If so, the connection may be wonky.

Peter Wieck Wyncote, PA

Reply to
pfjw

FYI, there is a rec.autos.makers.vw.aircooled that you should check out.

-- Mike Smith

Reply to
Mike Smith

SWAG that the float-valve in your carburettor is stuck. That or the automatic choke (which is electric in most cases.... did you re-connect the choke wire?).

i had already removed the valves and cleaned them out with some carberetter cleaner however i tried blowing thru them closing the valve and some times the valve would not open again with me blowing thru them. i also just installed a land rover defender electric pump (which i supose has more pressure and the engine lasted much longer before it started acting up)

as for the choke wire which is it and where is it (my mecanic clasess were all in spanish and my english terminoligy isint very good hahaha)

i do not think i do have an electric idle cut off as the only electrics ive done on the engine have been the coil and the alternator

thank you very much for such a quick response

P.S: what does SWAG mean??

Reply to
stefanbryant

Do you understand the operation of the float valve? It raises up and closes the valve letting gasoline into the carburettor. So if it is sticky and hangs up, you will experience problem.

Mpfffff.... typically it is brown, or green, or black or something... it goes from the harness to the circular thing that hangs off the top-ish of the carburettor and is about 40mm in diameter. Current is applied to it while the engine is running, it is bi-metalic strip that expands when heated and opens the choke. You will start a little hard without it, but you can start. The sovereign method to disable it is to look down the carburettor, loosen the clamp on the choke, then rotate it until the choke goes fully open with a cold engine. Resetting it is the opposite, but the goal is *barely* closed when cold, then reconnect the wire.

The automatic fuel cut-off wire is also brown, green or black, possibly red (yeah, I have seen all of the above and it makes no sense) and it goes to a little barrel-like thingy that also hangs off the carburettor about midway and is just under 25mm in diameter and about 40mm long with the wire on the end. This cuts off idle fuel, but does not affect normal running.

S uper W ild A ss G uess

Peter Wieck Wyncote, PA

Reply to
pfjw

well i know now what you are talking about it is all the way open.. it always had been.. it does not have any cable going to it however on the other car i have with the same engine it doesent have any cable going to it either an it runs fine

super wild ass guess... i like that!!

Reply to
stefanbryant

The float valve if closed should not allow any more fuel into the carb.. This is when the bowl is full of fuel and the float is floating at the top of its travel. As the engine uses fuel from the bowl, the float lowers with the level and opens the valve allowing fuel into the bowl till the float raises to the top and closes the valve again. The amount of fuel in the bowl when it is full and the valve is closed is about

5 minutes of idle run time. If the valve is stuck closed you will get the symptoms the poster discribes. Then after time the float weight trying to pull the valve up/open finally happens , maybe with a bump or knock . So the engine will again do the 5 minutes of run time then stop because it has used the fuel in the bowl again. >> as for the choke wire which is it and where is it (my mecanic clasess

I always used the word Scientific instead of Super , it makes the acronym more fun. Pete , please don't take my post here as an attack on you . It is not meant that way at all. You have usually always been right on with your info. and have taught me more than a few things.

Reply to
samstone

thank you both very much!! i just took apart the carberettors and gave theme an intense cleaning removed all the brass or copper screw things and clreared them out (one of theme was cloged; the one that is at the base of the resivouir) i think that was the problem... the engine runnes perfectly now it is however running a bit ritch. thank you again and best of wishes Stefan

Reply to
stefanbryant

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