Head gasket questions

[Bludge]

Ok, so i have been losing coolant for a while and getting a lot of white smoke from the exhaust although it sems to die down after a while of driving.

I topped the coolant up a month or so ago and checked it again today and it was below minimum. also noticed some sludge lining the bottom of the coolant resevoir. taking the cap off the rad revealed murky coolant too.

The oil looks a little coffee coloured but nothing like the oil in my corsa when the head gasket blew.

The car doesnt overheat at all, the guage has never passed halfway, even with "enthusiastic" driving.

So all the symptoms to me seem to point to the head gasket, but it seems that the car should be overheating somewhat?

Also i dont have the money to get the head gasket repaired, so i will have to try and tackle it myself. i have had a look at the manual and it made my head spin somewhat. does anyone know of a guide/writeup? or anyone who has done it have any tips for me?

Thanks!

[Angus]

Possibly HG failure, but hard to say. You'd be looking for definite signs of coolant contamination in your oil - it'll have a milky conisistency.

I'd be checking for other coolant leaks first. Check around your thermostat housing - couple of hoses, mating surface and joint to water pump pipe. Clean it all up and check again after your next drive. Check the ends of the rad hoses for signs of leakage. Check heater hoses, runs from under the distributor to the bulkhead and back. Look at the radiator as best you can through the gaps in the fans - turn the fans by hand to see more. Check around your rad cap for staining. If you can look from underneath the car, look for runs of dried coolant (pink stains if you use pink coolant).

[kris_aka_edu]

When I had the problem with my thermostat i had a look in my coolant over flow bottle and had some at the bottom of that, but I've had no smoke or anything nor overheating either. Seems by just doing a decent flush of the rad and pipes for a good half hour has cleaned it all out.

[Angus]

White smoke, by the way, is more indicative of coolant getting into the cylinders - which would indicate HG failure between the coolant galleries and one or more cylinders.

See Celica ST185 GT-fours, which all seem to do this sooner or later. I know mine did - did the HG myself. Not a huge deal, really, just lots of bits to take off and remember where they went back on. Plus finding someone to skim the head.

Could just be moisture in the exhaust pipe venting out, mind. That's why you often see folk with water dripping from their exhaust - condensation.

[Bludge]

well i took her for a blast just now and when i left it was smoking like mad and when i got back it was fine. didnt go over half on the temp gauge.

i wasnt really worried about it until i saw the sludge in the coolant and im worrying about oil leaking in to the coolant now. the coolant tank doesnt bubble from what i can see though.

i cant see an obvious coolant leak at all, although there is an oil leak but not sure where it is coming from.

*EDIT* also forgot to mention, the exhaust smoke doesnt smell sweet at all.

[wurlycorner]

Sounds like you definitely have some of the symptoms of head gasket failure, but not some of the others.

That's quite possible though. e.g. A failing/failed head gasket needn't necessarily cause overheating, I've had knackered head gaskets that didn't cause overheating and others that have (none on ludes). The last one was on Lisa's Volvo, which was using quite a bit of oil and small amounts of coolant, but didn't overheat, didn't change the colour of the oil, had no external leaks, no noticable smoke and no exhaust smell. I wonder if cats might mask smells in the exhaust from burning oil or coolant on modern cars?

I suggest doing a compression test, that's probably the best way forward to confirm head gasket or not (it's how I confirmed the Volvo).
Do you have a compression testing kit? You can get them for less than £20 (ebay, or pick them up somewhere locally for that price maybe?) Or are there any other members local to you that might have one you could borrow?

[jjmartin349571]

Just to build on the above, a hydrocarbon sniffer test would be worthwhile too, it should be cheap enough at a garage

[Bludge]

Yeah i will look into doing a compression test. hopefully someone i know will be able to provide a kit.

Depending on the results i will pay for a sniffer test too.

[Angus]

On the Celica, a compression test didn't show anything up - but a sniffer test did. Being as it shows up hydrocarbons in the coolant, it should be good for either oil or exhaust gas in the coolant. Having said that, my problem was purely between coolant and cylinders.

You won't get bubbling in the coolant unless it's getting over-pressurised (i.e. coolant to cyclinder failure).

For interest, here's my old and new HGs from the time:

[Bludge]

Well i looked it over with a mechanic this evening and it seems there is a slight missfire and oil on one of the spark plugs. i forget what he said the problem is likely to be, the piston rings or something was it? like at the bottom of the head they are ment to seal but sometimes they dont and let oil into the chamber?

And a nasty oil leak from the rocker cover.

He reckoned due to the car its not worth doing and not gonna cause much of a problem, but said he would do that and the head gasket for £150 if i supply the parts.

Im in two minds to do it or just leave it. with the bodywork in the condition its in, doing all the work isnt gonna increase the value of the car if i cant afford to keep it next year.
Although he did clear up a few things for me and i feel slightly more confident at giving it a crack myself.