How hot is everyone running?? Today I went for a long drive and hit traffic. The needle went half way from the middle to the H. I can't believe with one mechanical fan and two electric that a 1979 should overheat. My mechanic says that's just the way they are? Could it be the thermostat?

 

First port of call has to be the thermostat I would have thought, if the car has been OK up to now. Gradual deterioration comes from radiator clogging.

As far as I remember, these thermostats have an extension on them which closes off the by-pass port, so if you have a thermostat that only partially opens, some of the hot coolant continues to pass down the by-pass port.

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SNG Barratt - The Ultimate Jaguar Parts Specialist

 

Great advice from the UK !

Ken

 

A couple of thoughts in addition to the T'sat check. They do have a finite life. The last one I swapped out was in my 85 F150. Stuck closed ant it boiled like crazy. A new one fixed that and more. The old one also let the engine run too cool. Not good, either...


Is the space between the radiator and the AC condensor clogged with road debris? Bugs, leaves, etc.


And the face of the condenser? Clean?


Is it the guage mis reading the real numbers. If it is really hot, it should be gurgling noisy!!


Check with an IFR for the real temp!


Our cars have a emergency engine bay heat vent. Pop the Bonnett to
the 1st catch. A lot more air flow may relieve a temporary over heat.


And, if the man fan is a mechanical unit, it is suspect....


Carl

 

And/or flush the system and add fresh coolant.


Carl

 

My mechanic wants to remove the thermostat says that's what most people do. Won't that let the coolent move around too quickly thus not having time to cool in the rad?

 

Once the thermostat is opened after warm up it really doesnt have much of a role, so no its not going to do what you are thinking, its just that your mind is on overheating atm.

What it will do is slow down your warm up cycle , which could be really bad news come winter, if you drive the thing in winter.

All of Carls points are good.

I would replace the thermostat (may not be opening fully)
Flush the system to get as rid of as much crud as possible
Check that all the fans are working as you expect (just cause you have them doesnt mean they are working)

Dumping the thermostat is a kludge and will just (and even that is only a maybe) delay the inevitable real work that needs to been done. There is one is just about every water cooled car engine for a reason, it doesnt suddenly need to be tossed.

If its still running hot after all that there is still something impeding coolant flow, possibly blocked passages or a failing water pump.

 

Yeah, I strongly question the mechanic's advice on dumping the
thermostat.


For me, nope, even to the point of finding a new mechanic. But, as OI don't know what else he offered, I don't recommend dumping him/her!!!


Carl

 

If the coolant moves too quickly to dump the heat from the rad, it would also be moving too quickly to pick it up inside the engine. Old myth.

Removing the thermostat also solves nothing as Yarpos said.

 

True. Tis an old myth that removing the T'stats would make the coolant flow so fast as to hinder the heat transfer in the radiator. T or F, I dunno.


But, old racers thought so at "high" engine RPM"S. On flat head Ford
V8's a wheel washer fit the upper hose just right.


Others even removed or reduced vanes in the water pumps by grinding.


All to slow flow and allow heat transfer.


Others, said no so!!!


But, running cold is not good. So, for that is reason enough to keep the "stats".


Carl