87 coolant overtemp - help
Thread Starter
Cruising
Joined: Aug 2007
Posts: 12
Likes: 0
From: Pittsburgh PA
87 coolant overtemp - help
While running pretty good today the High Temp (~280) light came on and coolant boiling in radiator and overflowing resevoir.
Shut her down and everything cooled off, but it comes up pretty quick.
Oil temp was ~249 when coolant hit 280
Shut her down and everything cooled off, but it comes up pretty quick.
Oil temp was ~249 when coolant hit 280
Thread Starter
Cruising
Joined: Aug 2007
Posts: 12
Likes: 0
From: Pittsburgh PA
Yes, the fans are running.
I've also checked the other forums and will be sure the radiator is clear of any debris. The over temp occured after about 1 hour running time, temps in the mid 50's here in southwest PA today and I don't recall driving over any leaves, or other road debris.
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
If it comes up in temperature that quick that would indicate to me the thermostat is not opening and can could be the problem.
You might open the cap, let it warm up and see if there is any flow when you rev the engine some. Might also see if upper and lower hoses are getting hot at or near normal operating temperature.
Even if the fans were not coming on, at road speeds (45+) the impact air should keep it at a relatively normal temperature.
Of course in any kind of traffic it will get hot.
You might open the cap, let it warm up and see if there is any flow when you rev the engine some. Might also see if upper and lower hoses are getting hot at or near normal operating temperature.
Even if the fans were not coming on, at road speeds (45+) the impact air should keep it at a relatively normal temperature.
Of course in any kind of traffic it will get hot.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Leaves and other debris accumulate. It isn't a one time event that fills the area between the radiator and condenser. Once it enters, it never leaves. Start by filling it with water and allow it to warm to, with the radiator cap off. Watch the coolant flow to make sure the thermostat opens at the proper temperature. When you have verified that, let it continue to warm up and check the fan operation. Assuming you've seen no signs of a blown head gasket, and that the thermostat and fan(s) opens/comes on at the right temps, flush the living heck out of the cooling system. When that is done, to it again. Then remove the radiator and clean out the area between the radiator and the condenser. then, carefully clean and straighten the fins of both heat exchangers. Put it all back together, fill, including burping, with a 50/50 antifreeze water mix and you should be good to go.
RACE ON!!!
RACE ON!!!
Team Owner
Joined: Jan 2003
Posts: 20,304
Likes: 240
From: Summerland B.C. Canada
If it comes up in temperature that quick that would indicate to me the thermostat is not opening and can could be the problem.
You might open the cap, let it warm up and see if there is any flow when you rev the engine some. Might also see if upper and lower hoses are getting hot at or near normal operating temperature.
Even if the fans were not coming on, at road speeds (45+) the impact air should keep it at a relatively normal temperature.
Of course in any kind of traffic it will get hot.
You might open the cap, let it warm up and see if there is any flow when you rev the engine some. Might also see if upper and lower hoses are getting hot at or near normal operating temperature.
Even if the fans were not coming on, at road speeds (45+) the impact air should keep it at a relatively normal temperature.
Of course in any kind of traffic it will get hot.
Le Mans Master
Joined: Aug 2003
Posts: 9,884
Likes: 3
From: Magnolia Mississippi
St. Jude '03-'04-'05-'06-'07
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Team Owner
Joined: Mar 2001
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From: Cincinnati, Oh USA
The owners manual says to shut the engine off at 260 F and let it cool down. One easy thing to do as a test of your radiator being blocked by debris is to blast water backwards through the radiator with your garden hose while you hold the fan to keep it from turning. I would also see if coolant begins to flow while looking into the radiator filler when the coolant temp gets to the thermostat opening temperature. Be sure to open the radiator cap when the engine is cold and let it idle to the stat opening temp.