bmwe21.net forums

Hi there !!

Please I'm looking for advice, I got my E21 running after I've bought it disassembled, but it's idling and running quite rough - (uneven revs, stalling..)
upon investigation I've found that it's ''spitting'' fuel out of jets(looking down the carb) - even when you rev it and hold higher revs you can clearly see that it is not ''spraying'' the fuel evenly, but in bursts, making the engine quite
There is a simple homemade ''T'' piece in place of the valve between mech. fuel pump and the carb(for return to tank), I suspect the return is small, forcing the needle valve open and making this mess...sooo the question is, what are you running in place of the regulator , or is there any aftermarket return valve to mount in place of this ''tee'' I have ?? sorry I dont have a pic handy, but I hope you can understand what I mean

Thanks a lot !!

Btw car is a 318, with solex carb

I'm probably wrong but I thought M10 carb engines didn't have a return to the tank? I seem to remember us having to install one on my brief switch to injection..

Hi ! my car has two fuel pipes , I've heard that some cars got the return pipe, some didnt (different carbs maybe ??)
the stock regulator looks like this :

There is a pic. of it in haynes for 4-cyl. engines , it is mounted on inlet manifold..
Thanks for the help

Ah, this is beyond my limited knowledge. Hopefully someone else can help. I was having fueling issues at one point though, a new mechanical fuel pump fixed it - the rubber diaphragm can wear out after a while. They go for £15~ or so on ebay.

Thank you Reck! hopefully someone else will see this , now i think it's carb related, I managed to find older working valve but the problem stays the same...I can see carb rebuild in my near future
fuel pump works well...