Club 80-90 Forums

Just fixed a fault today and thought I'd post to see if anybody can guess what it was? ( I didn't guess right)
Also might help somebody in future.

I took some pics removing carb to help others ( a simple job but it frightens some) I will post them later.

Symptoms were gutless on petrol cold, couldn't even pull away without kangarooing, hot it drove but gutless, I have an air fuel guage so it was clearly lean.

Lpg ran fine, I thought maybe a bit under powered but happily got up to 70mph last weekend.

Partly blocked jet in carb our petrol pump faulty. Two guesses for the price of one!

ethelred the ready wrote:Partly blocked jet in carb our petrol pump faulty. Two guesses for the price of one!

Neither, blocked jet was my guess
Anybody else?

Secondary throttle diaphragm holed?
Linkage fault (secondary)
Choke flap not fully opening
Air bleed screw out.
Gasket failure.

Just my 10 p

kevtherev wrote:Secondary throttle diaphram

Spot on, well the pipe had come off.


I was amazed that with only one choke working it drove on lpg but not on petrol, I would have thought both would be similar and just under powered, why would it not even pull away, surely a single choke solex is similar to a single pierburg choke?

I agree mostly, but the lpg is delivered on demand and not metered.
The second venturi is just another inlet.
As such the performance would only suffer in high demand situations.
Well that's my theory

Well it sems that wasn't the only fault, an air leak as well, either the bypass valve or the lower gasket, did them both so not sure which.

It explains why the lpg worked fine because the closed loop system just compensates.