White Smoke from breather / boost return mod

[642855659]

I was driving the other day and the car was boosting fine in 1st & 2nd, once I got up to about 70/80 in 4th the car wouldn`t go any higher and felt restricted.

I pushed a bit harder and something went and there was loads of smoke everywhere,  got home after 5 mins.

I realised that the pipe coming from the back of the block ( boost mod)  was kinked and this could of casued the prob.

The car runs/ idles, but sounds rough , there is no oil in the I/C or boost hoses .

When I rev the car, I get clouds of white smoke from the hose coming from the back of the block, and only a little from the exhaust.

Anyone have an idea what this may be? Sounds grim to me.

Thanks in advance.

[G40supercharged]

White smoke usually means water getting in the engine. The kinked pipe may be unrelated as excess pressure can still get out of the dipstick tube (by blowing the dipstick out slightly). You may have a blown head gasket so that some water is making its way into the oil. This may also account for the rough running if not all cylinders are running properly. Check under the oil filler for cream coloured goo. Check spark plugs for odd colour. Do a compression test on the cylinders if you have a tester (quite cheap to buy).

[642855659]

I've done a compression test and these are the results,

CYL 1 No reading at all(170 psi in 2016))
CYL 2 95 psi (160 psi in 2016)
CYL 3 90 psi ( 148 psi in 2016)
CYL 4 95 psi ( 160 psi in 2016)

CYL 1 plug was wet with oil, the rest were black sooted but not wet.

Does this sound correct for a blown head gasket or something more serious?

Thanks

Mark

[G40supercharged]

That does indicate a head gasket failure. It's also possible that you have a damaged piston on cylinder 1. Hopefully the white smoke means water is getting into the oil and its just the gasket which is a relaively cheap/easy fix. The other 3 cylinders have the same reading which suggest they are OK; I wouldn't worry too much about the lower compression values from when it was done before as the reading can vary with how you do the measurement. Whatever the actual problem, the head will have to come off.

Regards,
Nick 

[642855659]

Ok cheers, I'll get it stripped down in a couple of weeks and check it out.

Is it worth getting the head tested or is it a waste of money

[PeteG40]

depending on the mileage, i'd get the head rebuilt while its off...

valve guides, stem seals, skim and the valves re-cut.

Used to cost about £150ish when i got it done, maybe £200 at a decent engineering place...  But worthwhile while its off.

[642855659]

Ok cheers,

I`ll get it stripped down and see what state its in.

MAXRPM list the metal headgasket for 50euro, seems a bot steep, using the Elring number they are about £15.00 on the web.

Is it worth using this headgasket instead of the the standard?

ta

[ereeiz]

If you're getting your head skimmed, you may want a suitable headgasket afterwards to take up the extra material that's been machined off the face of your head. I remember the world and his wife banging on about how good metal headgaskets were for G40's 10 years ago. I also remember Jetta being quoted a lot..... sure someone with some actual knowledge will fill you in, or search "metal headgasket" when on the main forum page (with all the topics on it) it should search every board in the forum and give you a result.

[PeteG40]

a proper skim won't take hardly any material off so a stock h/g will be ok.  metal ones are thinner for slightly increased CR

[642855659]

the one on MAX RPM is Elring 621.082, on TECDOC it lists this gasket as being for  1.4 & 1.6 adx/aea/aee/aex/ahs/akv/alm/anx/apq codes.

I`d rather fit the metal one if it`s more HD, If it fit this metal one it should be ok?

[PeteG40]

metal one are more prone to leaking if head isnt flat.

if you're skimming it you'll be fine

get an elring from elsewhere cheaper id imagine

[642855659]

Stripped it down today and found the problem, damage on cylinder 1 .

Head & gasket ok looking

Anybody got a good recommendation for a supplier for new pistons?

[642855659]

The damage

[Yoof]

Overbore time 

[642855659]

have you got any recomendations Pete for what size to go for, or where to get them from?

thanks

Mark