Club 80-90 Forums

Hi, I was going to change the needle valve as my van keeps randomly cutting out, and I've tried so many things to try and fix it. But the new valve from Schofields is longer than the original. I fitted it but the float can barely move due to the increased size. I was going to send the kit back, anyone else experienced this?

1985 T25 1.9 DG. Pierburg carb

Yes. A kit l bought had same oversize jet. So l used original instead.
Unfortunately l cannot comment on your erratic cutting out issue without you posting more info.

Thanks very much for the reply. I'll send the kit back as I only bought it for the needle valve. I shall start another thread concerning the cutting out issue, really hope someone can help.

pbar wrote: ↑31 Aug 2025, 09:20 Thanks very much for the reply. I'll send the kit back as I only bought it for the needle valve. I shall start another thread concerning the cutting out issue, really hope someone can help.

I have a spare shorter version you can have.

Just looking back at your photo l notice neither sport a spring?

Hi, thank you very much for the offer of the needle valve, it's very good of you, I may just take you up on that, please let me know what you would like for it. The two valves in my picture do have springs, they are internal. Was the carb set which you bought a 'Classic Line' one? And can you remember who it came from. I'm just curious as to whether they all have this same larger non fitting needle valve.

I really can't recall the source. It was a couple of years ago. And my brain has succumb to various NHS treatments since.
PM me your address and will put it in the post tomorrow..

Wow, what an absolute gent. Very much appreciated for sure, thank you. PM sent.

Big shout out and thanks to Stuart (maxstu) for sending me a new needle valve, just as promised. It arrived a little while ago and I fitted it and it's on the van. What a great forum to have that kind of spirit. Very grateful. I was hoping it would fix my random cutting out issue, and it did look promising but it's still doing it, so it's back to head scratching with that but it does rule out the needle valve. Thanks again.

Bugger! Only about another 100 Pierburg carb components to consider now....

What have you tried to date?

Change fuel pump.
Delivery quantity
Check carb is clean and float is correctly seated and movement. Give it a long blast of carb cleaner while revving above 3k
Air leak at manifold
Fuel pump rod wear
New fuel lines
Vacuum lines
Timing
Fuel fuel or air filter
Blocked fuel cap
Blocked fuel tank
Idle speed
Rotor
Dissy cap
Mixture
Plugs
Ignition leads
Ignition amplifier
Coil
Hall sender

Perhaps source or borrow another known working carb (l know, hen's teeth etc) from a nearby forum member to hopefully eliminate it actually is a carb issue.
I do have a spare carb, Paul. But as much as l trust you, it's not an item l want to lose in transit by a negligent postal service. Reasonably priced carbs are getting very difficult to find.

Good luck.

Regards
Stuart

Has the little mesh filter been checked for debri at carb fuel supply.
Also give the distributor caps points a clean and double check that all leads are in fully.
My lead from coil was in but not fully engaged, this was gibing me a bit of misfiring.
Just adding to Maxstu's list..

Thanks for the replies and advice guys, I appreciate it. I have tried most of those things.

What happens is, the van simply cuts out, always on idle, so when approaching lights, junctions, etc. It's often like turning a switch off. Although often I will sense it struggling/lumpy beforehand so I know it's going to happen when I coast to a stop. It's very random, I can drive 50 miles or more and it's great, or drive to the end of my road and it'll cut out. It can do it when well into a journey or on starting the engine or mid way though a drive, it can be a cold engine or hot, very random (like all the best problems), and I can't recreate the issue either which is making it hard to fix. Once it's cut out it will not start again and idle, it'll run lumpy with lots of acceleration but it's wanting to die and does on idle. It's happened dozens of times so I've 'messed' at the side of the road a lot, and the ONLY thing that'll get it going again is to squirt carb cleaner down the idle jet. Then it starts straight away, runs great and will often happily do so for many miles. Or, it may do it again quite quickly. So random and no rhyme or reason to it. At first I thought that the carb cleaner trick was clearing a blockage but after cleaning the carb repeatedly and finding nothing, nor any dirt in any of the filters (changed all three anyway, two inline at the tank and the carb one), I'm thinking that the carb cleaner is acting as easy start.

One time when it happened I took the fuel inlet hose off the carb and on cranking the engine there was a good supply of fuel, filled a glass in a few seconfds, so I can't see how there's a blockage before the carb, I have since replaced the fuel pump anyway as part of the parts lottery to fix it.

The question I keep asking myself (and everyone else), is why, once it happens does carb cleaner down the idle jet get it going again. What is failing to enable this scenario to happen? For example if it was the coil at fault, then a dose of carb cleaner down the idle jet wouldn't bring that back to life would it, I have gone through the ignition side anyway. Unless the carb cleaner trick is masking the actual fault which does lie elsewhere, I just don't know.

My next step was going to be to buy a new carb. What's stopping me is spending around £250/£300, and it not fixing the issue. Fine if it does though. Also, the carbs which are for sale from various places all seem to have something missing, the Schofield one for example doesn't have the lower body heating element, you have to drill and tap the new carb if you want it, whether it matters or not I don't know. But, it can't be the whole carb at fault can it, only an aspect of it. But what aspect I don't know, I was hopeful that it'd be the needle valve, thanks again Stuart, at least it's ruled out and it'll stay on the carb.

So in brief, van cuts out on idle, and only carb cleaner down the idle jet (or down the hole if the jet's removed) will get it started again.

Grateful for any thoughts, thank you.

Have you actually stripped the carb down completely and cleaned it out?

Hi, I've had the carb off and to bits a few times, cleaning, blowing through, etc. Not thoroughly but enough to at least have some change in behaviour I believe. But it's always the same issue, sometimes I'll get several problem free journeys, sometimes not, it's so random. What aspect of the carb are you thinking might be causing the issue?

I'd give the carb a proper strip down and into an ultrasonic cleaner. Clear out all the ports with an airline, all new gaskets. Make sure the float isn't sticking.. jets clean and correct sizes..
Ive now got like 4 pierburgs plus bits sitting around (ones a brosol) I had the opportunity to get a weber from a job so I plonked one on to see how it goes.

I'd also do a compression check just incase.. also perhaps.. maybe check your coil and amp.. coils can be really weird when hot sometimes.. so you might be looking in the wrong place for the issue