4SFE - Blown Head Gasket or....???

[l1ttle_d3vil]

Got a 1993 Toyota Camry running a 4SFE engine, done around 130,000km and never given any issues. About 6 months ago it randomly overheated while I was parked on the side of the road. Checked the fans, they were working, let it cool down and drove home. Noticed the radiator cap was stuffed so replaced that and its been fine since.

Couple of weeks ago started heading to Auckland, parked up for a couple of minutes and left it idling. Came back and could smell something burning... temperature gauge was off the clock. Let it cool down and nursed it home, now any time it gets put under any load (up a hill or something) you can pretty much watch the gauge go up, and it boils at about half way.

First thought is a blown head gasket, and my mechanic says given the temperature it reached it would have definitely done some damage, which I would expect. Odd thing is I did a compression test and it was bang on 120psi on all four cylinders.

A - is this too low? I can't find what the compression should be for a 4SFE.
B - if it was a BHG or warped head, what are the chances of being even on all cylinders?

Only other thing I can think of is it looks like the top radiator tank could be leaking, hence the overheating. But even if that was the cause, what are the chances of the engine being undamaged from the overheating?

Thoughts??

Cheers
-Matt

[sergei]

The blown headgasket does not show up sometimes on the compression test. The figures themselves are irrelevant and depend on the gauge and technique of the tester.

Start the car from cold with radiator cap open and full coolant. Look for bubbles as the car warms up. If you get bubbles your head gasket is blown.

There is possibility for radiator to be blocked. Check for temperature across the radiator (it should be hot from top to bottom). If it is very cold on the bottom while very hot on the top it means the radiator is blocked.

[RS13]

There is possibility for radiator to be blocked. Check for temperature across the radiator (it should be hot from top to bottom). If it is very cold on the bottom while very hot on the top it means the radiator is blocked.

This. I had a similar issue recently with a 3SFE Caldina, overheated all the way back from Arthur's Pass, turned out the thermostat was jammed shut. Replaced that, was perfectly fine until they came to the first hill, temp shot up and car boiled over again. Under the "advice" of a mechanic they'd put two lots of radiator stop leak in to fix the "BHG", which clogged the radiator.. so every time they came to a hill, the radiator couldn't keep up with cooling and the temp shot up. So if your cooling fluid looks a bit murky or rusty and the car has done over 200,000km, I'd be looking pretty hard at the radiator.

[Lloyd]

As above, compression test wont show much if a gasket is just blown a bit. A cylinder leakage test should show it pretty quick though (usually).

And compression numbers don't mean a huge amount, if they're even across cylinders then its generally a passed test. But again, tends to only show head gaskets once they're well and truly gone.

Check the basics previously mentioned and go from there. If its been off the top of the gauge for a while though...

[evil_si]

Whats the coolant look like?
Rusty water? If so pull radiator and get it cleaned.


Teekay head check will tell you if there is combision gas in cooling system, or as previousy mentioned start and remove cap while cold and look for bubbles or gas,

[l1ttle_d3vil]

Started the car up from cold today with the radiator cap off, warmed it right up and there were no bubbles at all.

Checked the radiator, quite warm on top and just slightly cooler on the bottom (still definitely warm though).

Water coolant is pretty clean, definitely not rusty brown water. Normally has antifreeze in it but I never replaced it last time I flushed it (probably 6 - 12 months ago)

I realise the compression test isn't a reliable method of checking the head gasket, but the fact it is all even seems a bit odd... Just want to make sure I've checked everything I can before pulling the head off.

[Bling]

No antifreeze?

[CAMB01]

Thermostat or bung radiator cap again. Had similar issues with a blown headgasket, air would get in behind the thermostat causing it to close. bottom hose would be stone cold while top hose would be very hot. temperature would shoot up hot as hot coolant couldnt flow to the radiator.

Any coolant going into the overflow?

[MilfHunter]

Thermostat - I had similar issues recently with a TEQ thermostat ramdomly giving me grief