Hi - Newbie here from Cornwall.

My mate has donated me his G reg 1.7 340 which he bought for 150 quid while his toyota was off the road for a bit. He no longer needs it - but it's too nice to scrap - just a bit of rust on the rear wheel arch and front of bonnet and one of the brake lights is dodgy.

I have travelled in it and it's very comfy. It only loses a little bit of water from time to time - no oil loss really. The prop is banging a bit underneath on low revs (possibly due to no oil in diff???) - The diff is covered in oily gunk - any ideas guys.

But the main problem is that the MOT and Tax run out at the end of April and that its got that common carb. problem where it runs on choke but as soon as choke is put in or gas pedal is touched - it konks out.

Not sure whether to sell as a donor vehicle to someone or try and get it going and bang it in for an MOT and see what happens (with my limited knowledge of 340 carbs.).

A local scrapyard has a Webber for a 1.7 for £29.

I have read some of your posts here about this carb problem where it seems that it could be inlet manifold gasket, air restrictor valve pipe thingy or just the carb. which is knackered and needs a refurb or replacement.

Any ideas guys. Don't wanna spend too much money on this car as it cost peanuts and the diff could be gone and might fail MOT. Unless I get this baby running again and to the MOT station we will probably scrap or sell for £150 ono.

I would like to get it going really because it's the comfiest car I have driven/riden in (until it stopped driving that is).

Any advice about the carb., diff gunk (banging prop) or saleability, please get in touch ASAP. Thanks.

James.

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The prop is most likely something loose, so when you get the car up in the air to check the diff I would give it a good wiggle and make sure that nothing's obviously loose. It might be worth making sure the prop clamp bolts are torqued properly to 37Nm too.

The oily looking diff is a worry as you say. They almost always leak from the back plate gasket. Its worth retightening the back plate bolts cos they were only tightened to 9Nm when they were fitted, so worth just checking those over with a torque wrench too cos they can loosen off as things compress.. (I would say very slightly overtorque them too 10Nm isn't a bad number ) Check and top up the diff oil too.

The carb is almost certainly the base warped. If it was the restrictor missing I doubt it would run at all. I wouldn't put a Weber on there. I know people say they're a superior carburettor, but I haven't found that's the case. They have no electronic preheater and you can't connect the water pipes to anything, so they're very temperature sensitive, and they have no anti-run on device so they run on and flood when they're switched off hot.

What I would do very carefully, is strip down the carb to its base shell, don't worry about taking all the jets out etc, but just to make it less clumsy to hold. Find a very flat sheet of glass or plastic, and place some fairly coarse emery cloth on to it.

Sand the base of the carb until its flat, then use a finer grade to smooth it off. I've had to do the same to the inlet manifold flange because that had also warped slightly, though not nearly as much as the carb. Then replace with new gaskets, although if the old gaskets are OK, you can reuse them, cos the kit from Volvo is about 90 quid

Hope that helps

Thanks for the advice matey.

I am away for a bit but will be looking at these things from next Monday evening onwards.

Just one more question about the carb - When the car was running nicely, when turning right (and usually up a hill), the engine jolted suddenly and then picked up again - could this be something to do with what you mentioned about the warped base? or is it something internal like split diaphram/float level or whatever. I know nothing about carbs (or 1.7 340 engines for that matter!!! - lol )

J.

I don't think thats the carb, I think the jolting round a corner is float height, mines been doing it of late (though only on rallys, and only when I properly attack the corner). Nearly put me in a hedge the other day as I had stepped the back end out, and the thing just bogged Luckily unlike anything agressive and rwd, backing off the power doesn't send you spinning, so all is good.

Float height you adjust/check (best do that the other way around) by taking off the 3 screws at the top of the carb, and measure the top plate to the floats themselves.

Thanks

Before we had this carb. problem, the mixture was very rich as well. The previous owner had the car idling at 1,800 RPM!!!!!! - We tweaked it down to around 750-800 and it ran better but the mixture was still very rich and the car stank quite a bit of petrol after a long run (even when cold) - 2 of the plugs (new) were a bit oily. We couldn't find a mixture screw on the carb.

Anyone know if there is one and where it is?? or is it internally factory set?

If so, can you tell me where it is - once the base is rubbed down, if it works again, I will need to reduced the mixture!!!

J.

yeah, you certainly will need to reduce it The screw is on the front edge of the carb, as it is installed in the car, inside the baseplate. It looks like the warpage problem has been occurring for sometime for someone to have adjusted the screws like that.

Chris will wait for his car to conk out completely before adjusting the floats in the carb

The carb prob. is fixed.

Just rich mixture - that's all.

Turned the screw in, and it runs fine now.