cooling
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Joined: Jun 2006
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From: cudjoe key fl
cooling
I have a 78 with aluminum radiator, new rad seals and hood seals, and a new gmpp zz383 engine. Before I did the swap my car always ran hot! Now I can't get it to run past 160. I started with a 160 thermostat because of the history of running hot. Went to a 180 thermostat and it still won't run past 160. All parts are brand new and am using Mr. Gasket high performance thermostats. Even after a nice long drive you can grab the upper radiator hose and it's not to hot to hold. I like the fact that it runs cool and I don't have to worry about overheating anymore, but I would like to get the temp up to at least 180. Anybody else have the same condition? Also I have two temp gauges. The stock in dash, and a new mechanical gauge with matching sending unit. They both read the same. I did this to rule out bad readings on the stock gauge.
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
I have a 78 with aluminum radiator, new rad seals and hood seals, and a new gmpp zz383 engine. Before I did the swap my car always ran hot! Now I can't get it to run past 160. I started with a 160 thermostat because of the history of running hot. Went to a 180 thermostat and it still won't run past 160. All parts are brand new and am using Mr. Gasket high performance thermostats. Even after a nice long drive you can grab the upper radiator hose and it's not to hot to hold. I like the fact that it runs cool and I don't have to worry about overheating anymore, but I would like to get the temp up to at least 180. Anybody else have the same condition? Also I have two temp gauges. The stock in dash, and a new mechanical gauge with matching sending unit. They both read the same. I did this to rule out bad readings on the stock gauge.
I've bought a 180 (or at least the box said it's 180), got home installed, not bothering to look at the them itself to make sure it's a 180 and noticed my car running at 160... I later found out that I bought a 160 therm in a 180 box.
It could also be a defective therm... test it, or just exchange it.
Is it really cold out where you are??? If it is, this sometimes can cause you car to not get upto operation temp.
Melting Slicks
Joined: Oct 2004
Posts: 2,662
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From: Knoxville Tennessee
Assuming you do in fact have a 180 t-stat installed, are you running the engine fan or electric fans? If you are running the electric fans they may be coming on too soon and need to be reset. Just a thought.
Bernie
Bernie
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Joined: Sep 2001
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From: Wellington, FL
St. Jude Donor '11 thru '25
A 180 degree thermostat is designed to open at 180 degrees and that should be the minimum operating temp of the engine after warm up. This being the case, it sounds like the thermostat is opening too early. I would replace it with another 180 and see if that solves the problem.
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Joined: Jun 2006
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From: cudjoe key fl
yes it is a 180 thermostat. It is stamped on the thermostat pill for lack of a better word. The thermostat does work, I tested it in boiling water. Besides the engine never reaches enough operating temperature
to open a 180 thermostat. And on top of all that I live in the Florida Keys and it's 80 degrees outside!!!
to open a 180 thermostat. And on top of all that I live in the Florida Keys and it's 80 degrees outside!!!
Burning Brakes
Joined: Sep 2006
Posts: 851
Likes: 10
From: Palm City, FL
A 180 degree thermostat is designed to open at 180 degrees and that should be the minimum operating temp of the engine after warm up. This being the case, it sounds like the thermostat is opening too early. I would replace it with another 180 and see if that solves the problem.
You need to test it, not in boiling water, but in a pot being heated, with a thermometer also in the pot... doing this you will see at what temp the thermostat opens. Putting it into boiling water only proves that it will open, but you still dont know at what temp it is opening at.
Team Owner
Joined: Oct 2004
Posts: 23,831
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From: Springfield MO
St. Jude Donor '07
A 180 degree thermostat is designed to open at 180 degrees and that should be the minimum operating temp of the engine after warm up. This being the case, it sounds like the thermostat is opening too early. I would replace it with another 180 and see if that solves the problem.
Sounds like a bad thermostat. Replace it with a different one, or at least pull it and test it in water that's between 160* and 180*.
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Race Director
Joined: Sep 2001
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From: Wellington, FL
St. Jude Donor '11 thru '25
yes it is a 180 thermostat. It is stamped on the thermostat pill for lack of a better word. The thermostat does work, I tested it in boiling water. Besides the engine never reaches enough operating temperature
to open a 180 thermostat. And on top of all that I live in the Florida Keys and it's 80 degrees outside!!!
to open a 180 thermostat. And on top of all that I live in the Florida Keys and it's 80 degrees outside!!!