1986 340(the results are in)

[Bazboy]

hmm i have no idea, the air filter and oil filter have been done recently. could it be linked with the fuel filter getting clogged? dan

[340GLT]

Yeh for the sake of a few quid i would swap it.
Adam

[Bazboy]

how easy is it to replace?

[340GLT]

Piece of piss it should be in the engine bay under where your spare wheel sat.
Adam

[Bazboy]

Ok went out today and had a look, its weird i did a compression test and all is fine. i also checked the plugs and they looked ok, and replaced the leads as two of them were broken. No change still runs badly. So then i checked the oil and noticed that the car ran fine with the dipstick out, it also runs fine when you pinch the vacuum tube connecting to the base of the carb.

Anyone have any idea whether this could still be a vacuum leak as i have sprayed with lynx and no change. Also the car ran fine for a bit then 2 mins down the road and its goes back to its old self.

HELP.

Dan

[pettaw]

go through that again, the car runs badly, but then if you take the dipstick out then it starts running properly? If that's true then your carb is set waaay too rich and the dipstick out is introducing an air leak to lean it out.

[Bazboy]

so it might not be an air leak? which way should i turn the screw to make the mixture less rich? and would a rich mixture cause the idle to pick up and drop randomly?

Cheers Dan

[340GLT]

The pipe that goes to the base of the carb will more than likely be at fault, follow it and check it is connected at both ends, if it is try replacing it with another length of hose.
Adam

[pettaw]

Make sure though, that the length of hose you replace has the air restrictor in it, otherwise you'll have a major air leak in it.

[Bazboy]

Hate to sound like a numpty but what is an air restricter?

Cheers Dan

[340GLT]

a bit of pipe that sits inside the vacuum hose but has a very small hole in the middle to 'restrict' the air.
Adam

[jtbo]

That restrictor is also often disappeared during car's history, same with mine too.

However I wonder how that would make air leak as ignition module has diagraph and it can't suck air trough it, right?

I believe it affects more to idle ignition advance and general ignition changing, but I can be of course wrong.

It is possible to restrict air flow trough that vacuum pipe with metal wire too, just twist metal wire around it enough tight and there is emergency restrictor.

[Bazboy]

Sorted, its all sorted, i am officially the happiest 300 owner of the day!!! Im not 100% sure on the cause but i removed adams carb and replaced the sparks and everything is perfect. I think either the sparks were mucked or i had set Adams carb up wrong and didnt have very good gaskets, I really should stop fiddling. Anyways im going to save the new carb for a time when i can sit down and set it up properly but for now im just happy having a smooth running B14.

So on with the Leo's

Big thank you to everyone who helped with advice.

Dan

[volvosneverdie]

Great to hear it mate!
Just in time for the bank holiday man.

[Bazboy]

Ok so as you may know i have started to refurbish the leo's i got from sven, I did a quick test fit with one today to see how it looked and i am very happy with it, this is not the final color and isnt the same wheel in the refurb thread, this is a quick job i did on one to get an idea for the color, and i am really tempted by white.

Enjoy













Cheers Dan