Club 80-90 Forums

My 2.0 cu engine is starting to test my patience

It recently completed a 300 mile trip trouble free but once or twice when under load for a prolonged period (ie 60mph) I noticed a very slight misfire. I eased off slightly and it was fine. However last week whilst driving up a steep hill it misfired and stalled, it started on the button immediately and stalled again after a few hundred meters. Once I was back on the flat it drove fine and got me home. I have started with the obvious and changed the rotor arm, dizzy cap, spark plugs and ht leads for new ones and this has made no difference. After a read up on the wiki I have now replaced the ignition module (I think that's what it was called) and that made no difference. Whilst on a test drive it seems fine until warm then after a few mins of driving at 50-60 mph it starts to misfire again. The weird thing is if I sit on the accelerator it gradually looses power however if i come off for a few seconds it is fine again for a while before starting again. I have checked all the vacuum pipes and they are fine. The engine has always been as good as gold, no smoke etc.

Any ideas??

Apologies for the long post but it thought it was best to state all I know and all I have tried to enable me to get the best advice

Cheers in advance

Gary

Not sure if it's relevant but I believe its running the standard twin carb set up.

Have you checked your fuel pump is delivering enough fuel? sounds like you're using up more fuel than its putting into the bowls. Then when you ease of the throttle it can then catch up and is fine for a while until your back hard on the throttle. Or it could just be some C*#p in the fuel line somewhere restricting flow

Check the length of the Fuel pump pushrod

Andy

What sort of fuel pump are you using? Mechanical or electric?

Apart from possible issues with the above, it sounds exactly what I had not long back. One of my carbs didn't have the float set right and at idle and up to 50-60 it was fine, however running at 60 for a while was enough to burn more fuel than went in....therefore basically ending up only running on 2 cylinders properly, resulting in loss of power unless I took foot off and slowed a little which let the float bowl fill up again. Took a washer out to let more fuel in and ran perfect!

Bonus with that was cost = £0!!

Cheers guys. I would like to change all the fuel pipes anyway. Might change them so I can rule out another element and get the pressure tested. I shall let you know how I get on

have you tried another coil

faggie wrote:have you tried another coil

No I haven't to be honest. Allthough it's no guarantee its a good one, the coil looks to be pretty new. It's something else to try though if the other things don't work. My dad's going to test the fuel pump pressure for me shortly. I've also ordered a fuel line kit from brickwerks. They don't look great and weather the running problem is related to the fuel line or not it certainly won't hurt to change them anyway.

Absolutely, main cause of engine bay fires be old hoses!

Hello,

Once you have finished changing the fuel lines..

and cleaned the fuel pump..

Then do all the vacuum pipes..

Then check carefully round the carbs to see nothing has come loose..Don't change any settings.

We might then address your misfire..

If you are happy with your (transistor ignition) coil..

Then you might think about this..

https://www.youtube.com/watch?v=KkyBAMM ... gNrGfa9EAg" onclick="window.open(this.href);return false;

and banish your 30 year old dizzy and amplifier..

Cordialement,

A little update. The van is now sorted and running as it should

here is how my process of elimination went:

1) check all vacuum hoses and change the ones that looked past their best. No joy.
2) replace the plugs, leads, dizzy cap and rotor arm. No Joy.
3) Temporarily swap the ignition module for one which I knew worked, No joy.
4) check pressure coming from fuel pump, all fine.
5) After noticing a small hole in the exhaust (a long shot I know) I changed the exhaust. Yet again no joy.

Then whilst having a little ponder over the engine late the other night I got my wife to fire it up whist I stood at the business end and what I saw was what looked like a firework display going off in my dizzy cap. Surely not I thought. I bought my second new dizzy cap and the van drove like a dream.

The moral of the story? DONT ASSUME THAT NEW PARTS CAN NOT BE FAULTY ASWELL

So it turns out all I needed was a new dizzy cap after all

Just as precaution I'm taking the van to a specialist on sat for a full tune up of the engine and carbs.

Yet again thanks to everybody for their help and advice