Over heated Ford (Mercury) Engine on my F8

[cletrac (RIP)]

Originally Posted by Bob Moseley

Hi all - I think ditching thermostats is the old wives tale. Go back to the grass roots of engine design where a need was assessed to incorporate thermostats. Sixty three years on the engine is not as efficient through the water flow areas. Fix that and you should have no problems.

The design need for thermostats was to warm the engine up faster in cold weather. This is all well and good with most motors but the flattie suffers with other design problems. If you're running one in cold weather then run the thermostats but in hot weather removing them increases the water flow and helps with the problem. I'd bet money that Fords in the Sahara all had them removed. It's just something that has to be done. The LRDG preferred the Chevs because of the heating and fuel consumption problems they ran into with the Fords.I ran flatties in the 60s in cars and trucks and the only way you could run them was by removing the thermostats. With Chev or IHC 6 bangers it didn't matter. The engine design didn't create the problem. It was accepted practice on the Fords to remove them when you changed to heavier oil in the spring.
Even when flatties were relatively new they were always on the verge of heating and too hot a day or too heavy a load would put them over the top. It's just the nature of the beast. Under these conditions you have to use any trick available to help out and you'll still have to watch the temp gauge.

[Anthony Main]

Jim,
What fan are you using,& did you fit a fan shroud ?

[Jim Price]

Anthony,
The fan is the standard 4-bladed one and no, I don't have a shroud. I have considered a shroud but don't want to contrict the possible air flow around the mainfolds. A 6-bladed fan might be a better addition.

I've considered all that's been said and believe that one of the two thermostats is not working properly. I recalled that when I tested them on the stove in a pot of water awhile back that one of them was slower to open than the other. I'm replacing them both with a pair of 160 F ones that came with the Mercury engine and are new. I also am considering adding an oil cooler to the system. (I am using a mono number weight oil, by the way.)

Thanks to all for your contributions to my thread; keep them coming!

Regards,
Jim

[Chuck Anderson]

Hi Jim,

I had overheating issues with the M20 armored car as well as the C8. In both cases I removed the thermostat and haven't had any problems with overheating or cold weather starting since then. I don't know about which is ultimately better, I just know that it worked for me.

Chuck

[Lynn Eades]

Im not familiar with your vehicle, but the lack of a fan shroud may be part of the problem.
without a shroud, the air may "wash" around the ends of the fan blades, instead of drawing the air through the radiator.

[Bruce Parker (RIP)]

If having thermostats to restrict coolant flow so it stays in the radiator a little longer is desirable, yet there is the possibility they are not opening as designed, would installing theromosts that are jury-rigged to stay open be a possible solution?

[cantankrs]

Hi Bruce,

That sounds like a disc of brass or something, with a hole drilled in it in place of the thermostat. I think I tried that with my engine mentioned above but wasn't happy with the results - non variable to suit changing conditions.

Also while I think of it I spose most people have heard of covering part or all of the radiator frontal area when very cold? You see it in photos, and colder clime people are probably familiar with it. I used to carry a piece of stiff cardboard I'd jam between radiator and grill on my old car when driving long distances on cold nights - so the engine would keep warm and importantly so I could get a bit of that thru the heater! It didn't completely blank off the whole width of the radiator just 2/3rd or so. And a working temp gauge is a useful guide in case you aren't cold enough.

Also some thermostats have a little jiggle device in a hole just nearer the edge and I presume it's to allow trapped air to release during cooling system filling, the jiggle may be to stop it getting blocked up. Some have a little notch pressed into the body such that the valve doesn't seal that tiny portion presumably for the same reason. I think older (or perhaps cheaper) thermostats had no such provision so I'd drill a 1/8" hole to one side. I'm interested in any instructive comments about this.

Regards

Alex
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M3 Grant, Val, Ferrets, WM20, CMP's