Overheating?

[dhs.buckley]

Originally Posted by Treeve

OK, so to get back on topic, you know your head gasket is backwards, but because a thermometer mounted somewhere completely different tells you a low temp you feel OK.

Except that a Windsor gasket mounted backwards would stop all the flow through one of your heads.

So apart from the fact that the heads are the hottest part of the engine, everyone here says the thermometer sitting miles away which isn't getting any hot water because you don't have any flow through one of the hot bits is fine.

I reckon a head gasket it cheap compared to blowing something more seriously. Check it properly, know for sure.

Treeve

Before removing the head I would put a laser temp gauge on the head and check several points to see if there are any hot points and compare the 2 heads. I found the laser temp gauge such a handy tool and they are not expensive anymore. I found that the temp gauge and thermostat where buggered on an old fairlane was reading 105c on the gauge in the car and with the laser on the thermostat and the temp sender it was actually 73c, new gauge and thermostat no more overheating problems.

[snakesaway]

Originally Posted by dhs.buckley

Before removing the head I would put a laser temp gauge on the head and check several points to see if there are any hot points and compare the 2 heads. I found the laser temp gauge such a handy tool and they are not expensive anymore. I found that the temp gauge and thermostat where buggered on an old fairlane was reading 105c on the gauge in the car and with the laser on the thermostat and the temp sender it was actually 73c, new gauge and thermostat no more overheating problems.

Oh yeah thats a really good point never thought of that. Thanks

[snakesaway]

Originally Posted by dhs.buckley

Before removing the head I would put a laser temp gauge on the head and check several points to see if there are any hot points and compare the 2 heads. I found the laser temp gauge such a handy tool and they are not expensive anymore. I found that the temp gauge and thermostat where buggered on an old fairlane was reading 105c on the gauge in the car and with the laser on the thermostat and the temp sender it was actually 73c, new gauge and thermostat no more overheating problems.

Well the temp test was interesting found about 30 degrees difference on the drivers side head at the back of the heads (this is the side I suspect the gasket is the wrong way around) but not much difference at the front of the heads.

So decent road test time drove it to work in the morning cool light traffic. So the temp gauge barely moved off the "0" of 180 F, crept up a smidge at the lights but not much. Next was the real test the drive home in the traffic outside temp was about 20 ish degress again not very hot. I did how ever sit in heavy traffic doing about 20-40 km/h for about 20 mins. Thermo fan on the temp got up to just shade before the "2" of the 210 F mark and stayed there (thankgod). Once I cleared the traffic and started moving again temp came back down to just above 180 F. So all good so far drove around in it most odf the weekend with no problems still no a particularly hot day. next big test is wait for a hot day and go for a drive and cross my fingers.

[07cob]

Originally Posted by snakesaway

Well the temp test was interesting found about 30 degrees difference on the drivers side head at the back of the heads (this is the side I suspect the gasket is the wrong way around) but not much difference at the front of the heads.

snakesaway

I put the gauge temp sender at the rear of the intake manifold at some stage and found the gauge read low. Very little heat regardless of driving. Moved the sender back to the usual place (front right) and temp was all back to normal.

Geof

[Jaydee]

The main problem with the temperature sender is it needs to be submerged in water. I have seen many overheating problems where the water was so low that it didn't register on the gauge. Or the customer has driven the car, it's overheated, they saw it on the gauge, pressed on, it's then lost all it's water and the gauge reading went back down. So they think it's alright. Then 5 to 10 minutes later, the engine starts to seize and the paint is melting of the block. The worst scenario, is that all the fluid leaks overnight, you then drive away with no water in the engine, the gauge doesn't register until it's to late. So what I've done is fit a airplane head temp gauge. It is a washer that has 2 bimetallic wires about 5 inches long and you screw the washer under the spark plug or a head bolt. As it heat up it sends a weak voltage signal to the gauge. No 12 volts needed. So if there is no water, it will still show the head temp. It's very accurate. It's a VDO gauge. It's really designed for air cooled engines. On my VW powered gyrocopter, I had one on either side cylinders.
JD