Engine stutter

[AndyDC]

Forgive me if this subject has been covered elsewhere.. I've just got home from a camping trip where my 1972 crossover experienced periodic bad engine stuttering. It appeared a few weeks ago when I last drove the van - but as of today it seems to be happenong more often - maybe once every 10 -15 minutes.

The engine effectively 'dies' momentarily, say six or seven times in the space of about 10 seconds, though it doesn't stall completely. All cylinders seem to be affected, and it's happened both under power up hills, on the level and idling at traffic lights. When it happens under power, the effect is a kangaroo hop - especially in low gear.

Maybe 4 years ago I had similarexperience - ended up stranded roadside after the engine stuttered to a halt and wouldnt restart. It was later diagnosed as crud in the (single) carb.

This time it feels more like an electrical issue. I'm due to go away again next weekend and I will have to cancel if I can't fix this problem. Points, leads and distributor were changed realtively recently. Does anyone have any ideas?

 

[StuF]

Do you have electronic ignition on your dizzy?
Sounds like you might need a electronic unit or dizzy - try a known good unit and see if it changes
Definitely sounds electrical

 

[Bigbear]

I had a very similar problem, it turned out to be the spark plug cap on the end of a ht lead, it had a breakage in it which when warm would cause it to miss a spark every so often, but when cold would work fine, It took three checks with the electrical tester to pin point it!

 

[Trikky2]

Also worth checking are the connections on the coil, continuity of the wires and the small earth wire on the points base plate. In addition it's possible the condenser or the coil is faulty. The only sure way to check them is to replace them - do you still have the old ones to try, assuming they were working ok before?

 

[AndyDC]

Do you have electronic ignition on your dizzy?
Sounds like you might need a electronic unit or dizzy - try a known good unit and see if it changes
Definitely sounds electrical

No it's not an electronic ignition.. But I had new points and leads put in relatively recently..

 

[AndyDC]

I had a very similar problem, it turned out to be the spark plug cap on the end of a ht lead, it had a breakage in it which when warm would cause it to miss a spark every so often, but when cold would work fine, It took three checks with the electrical tester to pin point it!

Thanks for this - Maybe the same problem that you had.. But it doesn't feel like just one cylinder is missing - all four seem to cut out at the same time.

Just spoke with my Guru Andy Keating of Mango Restorations, and he's suggested maybe the lead from the coil to the distributor is the problem, as they can come loose, or I guess just fail. I plan to check when I get home from work.. If not, it's off to see Andy to see what he can do..

 

[AndyDC]

Also worth checking are the connections on the coil, continuity of the wires and the small earth wire on the points base plate. In addition it's possible the condenser or the coil is faulty. The only sure way to check them is to replace them - do you still have the old ones to try, assuming they were working ok before?

Thanks for this Trikky2. That pretty well matches what I've just been told over the phone with Andy Keating - who keeps my van on the road. I don't have any old bits, but Andy K does and it may be that the only way to isolate the problem (short of anything obvious like a loose or frayed cable) is to replace all the components one by one. Because the problem is intermittent that might take a while !

Oh well - the joys of driving a classic!

 

[AndyDC]

I took the van to Andy Keating at Mango this afternoon and he tried a replacement coil. Bingo - I'm now running smoothly again. So looks like the weekend excursion might be on again

 

[Trikky2]

Glad to hear it's sorted with Andys help