7 replies to this topic

[Will16]

Engine: 998cc, stock
Model: 1991 Mayfair

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UPDATE: I still have the problem, car has had new plugs, coil, dizzy cap, points. It's all been set up correctly. When sat stationary, the revs waver about, then suddenly crash to just above zero for a few seconds, then I rev it and they continue to waver; this only happens below 1500rpm. This happens when the car is warmed up and has been driving for a while.

Could the carb need rejetting? Would electronic ignition help fix it?

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Went for a drive today, and at random points the engine started stuttering, usually when my foots on the accelerator, sometimes only slightly pressed and even foot to the floor. Then when I lift off, or pushed the accelerator harder it went away.

Any clue to what's up with it? I'm thinking it will be something to do with the fuel/carb? I took the airbox off and the cylindrical thing to the left of the carb had one pipe end split, with no clamp. Is this correct?

Edited by Will16, 27 January 2015 - 11:01 PM.

[blacktulip]

have you checked your plugs?

[jimnali]

The split pipe is an overflow to take any petrol spillage from the carb safely away from the exhaust.  Cut off the split end and refit it.  No clamp is required. This is a potential safety issue but should not affect running.

 

Start with the easy stuff:

1. Does the stuttering disappear when the car warms up?  Check that the choke working properly and that you have pulled it out far enough.
2. Check the oil level in the carb damper and if necessary top it up. 
3. Check that spark plugs are clean and properly gapped.
4. Check contact breaker condition and gap. (unless you have electronic ignition). 
5. Check condition of plug leads and distributor cap.
6. Check ignition timing.

At this time, a full service of the ignition etc is a good idea.

 

Good luck

[tomfsheps]

Check that your spark plugs are in the correct order! May be worth giving the contacting point a bit of a clean with some fine sand paper, or buy some new ones, not very expensive at least then you can say that its not the plugs.

[Will16]

Thanks for the suggestions guys.

I'll check the plugs tomorrow, I'm sure they are in the correct order though, as it was running fine, then it just started happening. I'll check the distributer cap too, could it be condensation in it? Should I try to dry it out?

I checked the dash pot oil and engine oil, and they were both fine.

The problem is still there when the choke is in and engine is warm.

[Will16]

UPDATE: I still have the problem, car has had new plugs, coil, dizzy cap, points. It's all been set up correctly. When sat stationary, the revs waver about, then suddenly crash to just above zero for a few seconds, then I rev it and they continue to waver; this only happens below 1500rpm. This happens when the car is warmed up and has been driving for a while.

Could the carb need rejetting? Would electronic ignition help fix it?

[hellom8]

Did you change the condensor as well?.

Have you checked the timing?.

Are your HT leads good?.

[carbon]

Sound more likely to be ignition related than carb.

 

Is your battery in good condition and alternator charging OK?