Thermostats

[rob love]

I found that years back the offshore produced thermostats were very late to open. On my jeeps, if I used a Canadian tire aftermarket thermostat, it would not open until almost 240, then drop down to the 180 mark. You might get away with that on a modern vehicle, but when you only have 7 pounds of pressure, you are hitting the boiling point at 240. A carrier is even less.

I had the same problems everyone is describing when I first ran my carrier. Even if idling, it would very quickly reach the overheat level. I had the rad cleaned, and also ran quarts of CLR into the block to try and remove some of the scaling. There are better products to remove the scaling, but you cannot use them with the water pumps in place as the harsher chemicals will destroy the pumps and possibly the head gaskets.

End of the day though, it all came down to having a fan as close to the radiator as possible, and having the shrouds in place. Because I am running an 8BA engine, I am not using the carrier generator. I managed to get a fan extension off a different Ford car or truck that worked out. It required a total manufacture of the shrouds though since the fan is in a different height than the carrier fan would be. I used the original shrouds as a pattern to make the replacement shrouds, and they worked perfectly and look the part.

I did try running without thermostats, and it did not make one shred of difference to the overheating. In the end, I think it really came down to the shrouds, and I now run 160° thermostats.

My rad cap is missing the guts to make it pressurize, so I am running without any pressure. Also, due to the climate here, I am running 60/40 antifreeze mix. Running stronger antifreeze mixes can also cause overheating, but I suspect that for most of the MLU guys on this thread, over-strength antifreeze is not an issue.