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(1982 Manual 320/6)

Afternoon all

So I think I've done the HG, symptoms are:

- Blue/white smoke from exhaust, not huge thick clouds but noticeable when stopping/puling away (seems to stop when I floor it in 2nd gear).
- From cold start, with cap off rad expansion tank I can clearly see bubbles forming, more so when I rev hard.
- Oily film on top of coolant in the rad expansion tank.
- (May not be relevant) Sometimes erratic idle speed

Things I'm not seeing:

- No sign of water in the oil (filler cap is clear etc, no mayo).
- No overheating.
- No loss in power

Recent work carried out (not that it should have caused these symptoms, but just to be clear):

- New radiator (system was hose flushed several times)
- New clutch slave and master cylinders
- New brake master cylinder
- New plugs, dizzy cap and rotor
- Oil and filter
- New exhaust mid and rear
- New cam belt and tensioner

If anyone could throw their opinions / ideas in the hat I'd really appreciate it! I am considering a cylinder head overhaul, a job which would be way too much of a task for me I think, but if anyone could recommend a good guy/gal in South London/Croydon I'd appreciate it... I was thinking about going to http://www.motortechengineering.co.uk - has anyone anything good/bad to say on them at all?

Also, has anyone ever simply 're-torqued' the head bolts and managed to cure (or prevent) similar problems? I suspect it's a little to late in my case but I'm quite interested.

I definitely want to stay with this engine - would rather that than to swap in something else.

Thanks in advance
Dave

If the smoking is not to heavy, I wouldn't be to worried. But if you look at the movie below, you know for sure the head is cracked (different car I know, but we had to swap the complete engine as the cilinderhead was cracked on several places).



Also you can do a compression test, if one cilinder fails you propably have some work coming.

Well the bubbles in the cooling system are worrying though. Easy checks: compression test (stone cold in this case as M10 head gasket failures show the most leaks cold to my experience), check if there are color differences between spark plugs. A decent garage can do a gas test on the cooling system as well.

Idle problems, do they occur cold, during warm up, warm? Did you try to re-bleed the cooling system (see FAQ section)?

Jeroen, pay attention, a 320/6 means a M20 ofcourse!

Hi guys, and thanks.

Yes, the coolant/rad system was bled, but I'll do it again to see if that helps.

It definitely seems to have lost a little coolant this week, and the oily film on top is still there.

M20 engine as pointed out, thanks.

Will look into a compression test and gasses in the coolant test also.

Today the engine has started stalling, first when it was warm after driving for an hour, made it home but was tricky. Went out later and seemed fine at first but quickly started stalling again, at this point the engine was cold... Funnily enough since this stalling started it seems there is a lot less exhaust smoke! Coincidence?

Thanks again
David

Hi all

Okay so I need to get the car to a garage to run some tests but I'm still stuck with this idle / stalling issue, here's what happens:

- Car starts with ease
- Idles well when cold for about 5 mins
- Will then start to idle low and eventually stalls
- It will start again straight after and if you keep the revs up it will keep going

It feels to me like perhaps the carb is getting flooded, that would explain why it runs okay for a little while, but then as fuel builds up it stalls.... I'm wondering if the needle valve may need replacing... what do you guys think?

This is the standard solex carb, and I have tried running cleaner through it but with no change.

Cheers

Auto choke stuck on maybe?

Andy, thanks for that... it doesn't seem that it's the choke to me, because prior to stalling the rev range is good, unless I need to adjust the idle up so that when it comes off choke it falls to a good level.. Hmmmm

You still got the factory carb? Get rid and put a Weber on. It'll save you lots of headaches.

Any vacuum leaks or any air hissing sounds when its ticking over

Hi guys

I have considered the Weber route, but there are varied opinions on that and if the Solex isn't warped I think I'd like to stick with it for now, perhaps get an overhaul kit.

I've checked again today for vacuum leaks, no loose or split hoses, checked using carb cleaner too an no change in engine note... I have to be quick checking this as it starts to stall after a few mins!

Can't hear any hissing either, any other ideas?

I need to run it with the air filter off and see if too much fuel is running through the carb, in which case the needle/float valve perhaps? I also read somewhere of the spring within the choke losing tension and causing stalling.... Anyone else had that problem?


Thanks