Smoking When Hot

[DooBeDooBeDo 1]

Hi,

 

My 1.9 smokes when it's hot. Not when it's just at normal running temperature, but if I'm sitting in traffic and the water and oil temp start to rise after the fan has kicked in 3 or 4 times then as soon as I pull off to trundle a bit further it belches loads of smoke (big thick cloud - really embarrassing)

 

I also get puffs of smoke when I pull away after it's been sat all night or all day or when I accelerate really hard.

 

I just did a compression test and got (from 1->4) 170,170,160,150. Plugs 3 & 4 were slightly wet with oil at the ends of the threads but the business part was dry.

 

I know the stem seals need doing but I'm concerned that the rings might need replacing it's done ~130k.

 

Any advice welcome.

[danpug 1]

Possibly the rings or maybe the valve guides. My old 8v smoked when you pushed the throttle and it turned out to be the guides.

[DooBeDooBeDo 1]

If it is valve guides, what is the remedy?

[danpug 1]

A head rebuild i guess. Its not a common problem afaik but a possibility. Its a bit strange it only does it when really hot though.

[steve@cornwall 100]

A head rebuild i guess. Its not a common problem afaik but a possibility. Its a bit strange it only does it when really hot though.

 

If you pull out the dipstick does the oil smell of petrol? Does it have a "powervalve", FSE or similar?

[DooBeDooBeDo 1]

The dipstick doesn't smell of petrol.

 

I'm not sure what an FSE or powervalve are, but as far as I know it's 100% original. It doesn't even have an induction kit.

 

It does use bucket loads of oil normally though (~2.5 litres every 500 miles). I have a little oil seepage from the front of the engine somewhere which I've been trying to track down but that's about a drip every 3-4 days. It really billows smoke when it get really hot in traffic, once I get going again though it stops and gets back to normal.

 

I've noticed that the oil pressure has dropped by a whole mark on the gauge from when I first got it too (about 2 years ago).

 

When I pulled the plugs to check the compression 3 & 4 had a crusty looking grey buildup on the electrodes, 1 & 2 looked fine. I put a new set in anyway.

[jpmatrix 0]

Depending on the colour of your smoke, and from what you have described, it may well be your head gasket that is knackered.

 

I had very similar symptoms on my 1.9, and the cause of it was water finding its way through the headgasket in to one of the chambers and burning off as thick white clouds of smoke as you described. It is more noticeable when the temp rises, because the coolant system becomes more pressurized(hotter), thus water will find the weakest point in your headgasket, be forced into one or more chambers, and burnt off immediately.

 

The overnight symptom of loads of smoke billowing out the exhaust on start up in the morning, is the result of water being forced under pressure from the coolant system into the chamber while your engine is cooling down overnight. Thats why you get s*it loads of smoke / steam on start up, due to the build up of water in one or more cylinders.

 

It only takes a tiny bit of water to get in one of the chambers and I tell you, you get fog banks coming out the back.

 

You going to have to take the head off anyway, so inspect the old head gasket for any signs of damage. And you might as well change the stem seals, as these come with the headgasket kit.

 

Good luck.

Edited October 16, 2007 by jpmatrix

[j_turnell 137 3 Cars]

If its blue smoke then it will be valve guides or piston rings, i'd do a compression test, do a dry and wet test and compare the readings, that should rule out rings, as already said vlave guides are common to fail on that sort of mileage, more than likely on the exhaust side. If its white smoke then thats burning water which will more than likely be the headgasket failiure, obv this time of year it will do it in the mornings but thats just condensation but shouldn't when hot.

[DooBeDooBeDo 1]

Thanks guys,

 

I've just bought myself another car (a really boring one) so I can strip the engine at my leisure now, rather than rush to do it in a weekend and hope that I'll have it done in time for work on Monday morning

 

I'm pretty sure the smoke is blue -> oil not white -> steam, but maybe I'm getting both when it gets really hot, although uses loads of oil and hardly any water.

 

I think the engines just getting old and tired and in need of some attention. A bit like me...

[jpmatrix 0]

Mmmm. If it is the piston rings that are worn, you would notice an increase in pressure in the crankcase and this would lead upto the cam cover. Take off the the oil cap while the engine is running ; if there is alot of pressure coming out, then your rings need replacing.