QuestionHi Christian. I blew out the jets, now the car starts immediately. It's still running rough though. I had a helper tonight, and he noticed that as soon as the car is running it sprays atomized fuel out of the choke tube. We switched places and I could see it looks like the spray from a paint can, coming up about six inches. We checked everything else that we could think of, but had no luck. Any ideas?
AnswerSo there's some blowback from the carb - Valve sticking open or closing late - so gummed up valve, worn valve seat or slipped timing.
It's likely confined to one cylinder, as I think it's a sticky valve.
Get the rocker cover off and turn the engine with a ratchet, check operation of the valves.
Theres also the possibility of gas leakage between cylinders causing blowback...
So head gasket ot head/block damage.
The best and worst are there, start with the easy stuff.
I think you'll find a stuck open valve looking very obvious once the cover is off.
This sort of thing is often due to sludge build up in the upper oilways, starving the top end and overheating the valve gear, making more sludge...
Check the condition of the oil.
