...more engine help!!

[Benyon]

My engine problems have been mentioned before, occasional loss of power as if running on three or sometimes even two cylinders. Took the van to the garage to get twin Webers and pertronix ignition fitted and thought this would resolve the issue at the same time. Mechanic struggled to set up claiming cylinders 1 and 3 were not firing correctly. The enging runs rough at tick over, but doesn't struggle, smooths out as revs increase but when driving the loss of power is still evident at times and there doesn't seem to be much of a pattern of when it occurs. Power is definately increase with the addition of the carbs.

Suggestions of what this could be? The mechanic did a compression test and each cylinder was within 10% of each other (I think thats what he said), leads and plugs were replaced in May...

 

[james_stan]

Tappet gaps ?

Crappy/old HT leads ?

Cracked distributor cap ?

Leaking rubber manifold joints ?

James

 

[Benyon]

Leads and dizzy cap were replaced in May this year so hoping I can rule that out! Rubber manifold joints were what I was hoping to pin the blame on but obv these have gone now with the twin webers and the problem persists.

I am now thinking the problem is internal to the engine...

 

[Tofufi]

What were the actual compression figures?

I'd check the valves just to make sure nothing is amiss there. When were the spark plugs last changed / checked?

 

[currylager]

WHS!! It sounds like possible cracking between the valves in the head, a compression test will usually prove this :wink:

 

[mIKe cAIn]

Leads and dizzy cap were replaced in May this year so hoping I can rule that out! Rubber manifold joints were what I was hoping to pin the blame on but obv these have gone now with the twin webers and the problem persists.

I am now thinking the problem is internal to the engine...

dont assume new parts will work, smometimes they are faulty!

 

[Benyon]

Cheers for your ideas guys!

The plugs were replaced in May and I have visually checked them. After a run down to Newquay last week the engine runs fine when driving in any gear at a reasonable RPM, the problem is only when I lift off the throttle or start off at low revs. It has reduced significantly since the twin carbs & electronic ignition but not altogether cleared up!

Could this be related to the sh*t Monza exhaust?

 

[Guest]

a stock exhaust would be alot better than the monza, or fit a beetle exhaust as its less restrictive.