Hi all,
A friend has an old Vauxhall Carlton 1.8 and when under load (eg going up a hill) the engine just starts to die. If he lets off the accellorator the engine picks back up and runs ok again.
Any Ideas? I was thinking maybe carburettor or timing?
Regards
Graham
|
Graham
I'm assuming this is a carburetor fed engine. if so this sounds like the mixture is weakening off when the throttle is opened. Needs a check of the carb. I don't know which one this uses, but suspect blocked jets or faulty diaphragms at a guess.
Regards
John S
|
|
Add the mechanical fuel pump to list of suspects, and any blockage between tank and carb. Does the car use those metal sparkplug shrouds as in the Cavaliers(83 on)? They had a habit of diverting the spark energy to ground. How is the rest of the ignition system? Good luck.
|
Hi Graham
Had one of these old girls for 12 years. Best car I ever owned. Could be a few things. Pattern part petrol pumps do not last. If one is fitted get a Vauxhall original, something to do with the lenght of the arm apparently. They were fitted with a Zenith carb(I think) again not the best. Changed mine for a Stromberg, made a huge difference. The distributor can cause many faults, it has a chip built inside which you cannot see or change. When the original one on mine started playing up the wipers would come on on their own, the rev counter would go berserk then the car would stop. Give it five minutes and she would go again. Spoke to other owners who had all sorts of weird things happen when this chip played up. Let us know how your friend gets on
Alyn Beattie
I'm sane, it's the rest of the world that's mad.
|
Sorry the old brain is getting worse. Changed the carb to a weber. Time for my tablets I think :-)
Alyn Beattie
I'm sane, it's the rest of the world that's mad.
|
|
|
|
It's The Old Guy again with a tale from the past.
I had a Morris Minor than ticked over smoothly and ran fine on small throttle openings but misfired on one cylinder under load. It turned out that under light load the spark plugs would fire OK because the spark had a fairly easy path across the electrodes but when the throttle was opened to let in more air, the resulting increase in compression pressure in the cylinder made it harder for the spark to jump from one electrode to the other and on the problem cylinder it would take the easier path from the top of the spark plug to a copper pipe that ran close by (ie. the automatic-advance vacuum pipe connecting the carburettor and the distributor).
What's that got to do with the Carlton problem? Probably nothing, except to demonstrate that the fault could be an ignition system problem and these are not always easy to fathom.
|
I'd go along with that. I learned long ago that on old cars, ignition system faults are far more common than carburettor faults, and that just because an engine dies when you open the throttle, that doesn't mean you have a fuel starvation problem. I actually got as far as changing the engine on my Herald (couldn't get a rebuild kit for the Solex carb, so I fitted a Toledo engine with an SU) before I worked out that the random misfire and occasional cutting out was actually due to a duff coil....
Richard Hall
bangernomics.tripod.com
|
|
Coils cause an awful lot of problems but as long there is some spark no-one checks them.I've had several cars where a poor spark has been the major cause of the problem.
|
My suspicions lie with the Ignition system. Check the following:
Distributor cap for cracks/tracking internally, condition of centre electrode and corrosion of the plug lead receptacles.Check the rotor for cracks/tracking.If at all suspect or more than 12 months old replace both items anyway. Check the coil tower for visible cracks/tracking on the 'nose' of the coil and corrosion of the king lead receptacle. Remove the plug leads from the plugs and look inside the caps for evidence of tracking or burning. Remove the metal heatshelds for now and remove the plugs. If at all suspicious of these replace them for new ones (I prefer NGK BPR6E-VG set to 0.7mm). Refit the plug leads without the heat shields and see how she goes.
Good luck.
|
Thanks for all your help. Ive forwarded all your ideas/comments on and will keep you informed of the outcome.
Regards
Graham
|
|
|
|
