Poor running

[Martin S]

Hi all...after a age i have managed to get the car back together. ....fired her up....and missing sounds like its running on 3......new plugs fitted. ..went to halfords and got some ignition spark testers that fit to the plugs....tested all good....its running megajolt......i had the carbs rebuilt could that be the problem? Both carbs are getting fuel.....any ideas.....many thanks

[DJ.]

As the car was running well before you stopped using it. I hear modern fuel goes off really quickly, so I would consider draning the tank and filling with some fresh super unleaded before spending any money.

Hope this idea helps

[Matth93]

I would take the plugs out and check them if ones wet that’s the one that’s misfiring if it’s wet it’s also not a fuel problem. Clean and dry any wet plugs or put another in and try again. If none of them are wet then it’s probably a fuel problem ( blocked jets maybe) assuming you’ve got good compression on all cylinders

[Martin S]

Argh some great ideas....the fuel has been in there for about 4 months so a drain sounds a good plan....the carbs have been cleaned and rebuilt. ..note not by me......i have noticed that on fitting some new fuel lines i must have knocked the fuel regulater down to 1bar....i have turned it back up to 2....but no difference

[Fury1630]

Not an expert on your set-up obviously, but I thought carbs wanted about 3PSI? 2 bar is about 30PSI.

Also, wet the exhaust pipes, then start the engine, if all are firing the water will evaporate almost instantly, if one pipe stays wet it's not firing

[Tony T]

If it hasn't run for a long time the cilinders need oil .A small amount of oil in to the guilty one You will have to pull a lead of one at a time to find it or them

Tony T

[steve m]

Was the cambelt changed? as it could be a tooth out, and on a pinto will run, but wont rev over 4k, if fitted incorrectly also sounds like a misfire and very lumpy, I know this by experience !!

Could it be running on two cylinders, as two leads are the wrong way round ?

Richard, had something similar on the green monster (Dutton) and I don't know how he fixed the problem, but that was running a twin downdraft carb

steve

[Martin S]

Sorry tony i mean 2.5psi...doh.....no cambelt change...just had the carbs done....and a blow on the exhaust fixed......will try the oil trick.....cant see how the leads a wrong as they are all connected together at the correct lenghs....going to speak to a guy later in eastbourne that does these for a living he has rolling road ect...think it is something silly as havnt touched anything else.....thanks for the advice guys

[leegav]

airleak between carb and head? spray a bit of DW40 around it to find out.

[Tony T]

If it hasn't run for a long time the cilinders need oil .A small amount of oil in to the guilty one You will have to pull a lead of one at a time to find it or them

Tony T

It's because the oil can drain away from the rings and the liner so you should get the oil to the edge of the piston not all engines suffer from it some ford's and my Vauxhall XE I try to start it every 4 or 5 weeks at least until the fan comes on then i get no trouble

Tony T