Club 80-90 Forums

Hi, I need some help please!

I've got a problem with my engine and I'm keen to try and fix it myself using advice from this forum (and the wiki/tech archive) and a Haynes manual - however I'm a complete novice and can't decide what to do next! (after changing the inline fuel filter if you've seen my earlier post)

So, the problem (Hopefully I'll describe it well enough for someone to say "Oh, that's... you just need to..." but in reality I suspect not!):
- It started with it sometimes, but not very often, cutting out under braking with the oil light and battery light coming on on the dash simultaneously, this happens both from cold and when the engine is warm (I've also noticed the oil light flickers very occasionally at other times). It has always started back up immediately when this happens and carried on running... as an intermittent problem I'd just accepted this as a "quirk".

- Since last weekend there is what feels like the engine is being starved of fuel at times throughout the entire range until it gets to cruising speed (about 60-65mph). Is this what people mean when they say their engine is running lumpy?

- I changed the fuel filter (putting it on the right way having taken the old one off which had the flow arrow going in the wrong direction)

- I started it up and let it run on idle on the drive for a few minutes cheked for leaks and then took it for a drive. It was OK for about 1/2 a mile down the road then it cut out under braking, but restarted immediately. After that it was an absolute dog to get moving. I had to give it quite a few beans and "bounce" the clutch to get it moving at all. Then, once moving it would randomly "pull back" (as if getting no fuel) then rev hard and accelerate. It cut out and restarted several more times on my way back home but made it safely back into my drive (got a lot of strange looks from the folks in my village)

What's wrong? What should I try next?

Thanks in advance...

Id start by some basic checks on air leaks

check the small vac lines from the carb, two towards the front of the vehicle, left had one as you look from the rear goes to distributor and the right hand one to the air filter, pull them both off from the carb and suck, them blow, you should not be able to such or blow fresh air, then replace them,

then start the engine and remove the distributor pipe and see if the revs drop down.

Next look at the vac connection from the Left hand side of the manufold to the brake servo and see if the pipe looks Ok or deteriourated?

Next with ignition on but engine not started pull the electrical connection top central off the carb and reconnect listen for a click.

whatever you do be methodical, one thing at a time, never two things,write down what you did, take pictures and report back

More like starved of air I would think.
Does it run smooth when idle or does it cut off after a while?
How long since last oil change on engine and gearbox?

Those symptoms sound quite similar to what I experienced when I had dirt in the carb - mine would work fine on full throttle, but felt starved at other times. Cleaning the carb out and blowing the jets through with an air line solved it for me.

Some great ideas there, thanks everyone - I'll be sure to do things methodically and write down my findings (coming from a scientific background that kind of comes naturally anyway!)

I changed the oil and filter myself about a month /300 miles ago. Don't know when the gearbox oil was changed. It has always been smooth on idle and will seemingly run forever with no problems (longest I've left it is about 15 minutes).

Just remembered something else which may/may not be relevant - the starvation feeling I described has only happened from about 75 miles since the last time I filled up, at that time I put some redex fuel system cleaner in as advised by the previous owner... is this good practice with these engines?

Also, it's got a Weber carb if that makes any difference to anything...

Hi,

The weber has a filter built in, be worth checking that's not gummed up - if you look where the fuel line goes in there is a big brass nut - undo that and there is a brass gauze filter. Give it a rinse (clean fuel of carb cleaner) and pop it back in.

Have you changed the air filter as well?

Cheers,

Alex

Not sure why I was told it has a Weber carb as it is clearly a Pierburg on closer inspection!

I didn't really do much tonight, no real time to tinker but I did have a good old poke around to try and familiarise myself with some of the bits and pieces described in your posts above. Now that I feel a bit more confident (or perhaps just a little less confused!) I'll have a proper go at it tomorrow night and report back then...

Hoping to be able to make it to the North West VW Show at Tatton Park on Sunday!

Update:

I removed both small vac lines from the front of the carb. Couldn't suck or blow down the one to the distributor. However I could suck and blow fresh air through the one to the air filter! There was a hiss from where the vac line connected to the filter housing. It looked a bit loose. I pulled the line completely off and put my finger over the end to seal it and then sucked it to make sure it could hold a vacuum. No problems there so the line itself isn't damaged.

I put it firmly back on the filter housing and tried sucking/blowing again. Nothing. Great

Reconnected the vac line to distributor, started engine and then removed it, revs dropped.

Got about 1/2 mile from house, no problems. Then pulling out onto main road the symptoms returned. Started to head back home and engine stalled when stopping to make a turn. I made round the turn and pulled over. Handbrake on, ignition off. waited for a moment or two then re-started engine and pulled away No problems. Carried on heading home. No problems. Decided to be brave and head back away from home and drive for a bit longer...

Drove for about 15 miles.No problems. Stopped at shop for about 15mins to pick up some refreshments. Restarted no problem. Drove the 5 miles home. No problems!

I'm going back out tomorrow night for another test drive to see if the problem stays gone. Fingers crossed!

Try taking out the air filter, giving it a short run and seeing if it still does it. They get clogged in this hot dry weather and lack of air is just as bad as lack of fuel. If it cures it - fit a new filter.

Another 20 mile drive tonight with no hiccups at all. Woohoo

Must have been the vacuum hose connection to the airfilter that was causing the problem.

Thanks everyone for your helpful replies...

I'd feel happier now replacing those vacuum lines now, just after a bit of re-assurance before place an order.
Is it this...
http://www.brickwerks.co.uk/index.php/p ... tural.html
... and this...
http://www.brickwerks.co.uk/index.php/v ... braid.html
that I need

I'll also be replacing the air filter too as I've no idea when it was last done