2001 GT Conv Water Pump Question
10-16-2013, 07:30 PM
#1
Thread Starter
Join Date: Oct 2013
Location: NM
Posts: 4
2001 GT Conv Water Pump Question
I just bought a 2001 GT Conv with 73,000 miles. Last week I noticed the cooling system overflow tank was boiling over when I got home. Researched many forums and checked many things. Gauge is at center indication, cooling system water/antifreeze looked good. Oil not like milk shake, installed new thermostat, replaced radiator cap with new. burped system. Still boiling over. I tried taking out thermostat no help. I was thinking my pump was bad. My question is, I took off the upper coolant hose from thermostat to radiator at the radiator. The thermostat was removed for this test. I put running water hose in overflow tank while I started the engine. I figured the water would pump out at idle speed doing this. If no water out of the hose = pump bad. Well at idle there was a slight trickle of water. As I increased engine speed the water finally started but went away as engine went back to idle. Is this normal? Any Ideas? Thanks 
10-17-2013, 09:24 AM
#2
3rd Gear Member
Join Date: Nov 2012
Location: North Carolina
Posts: 574
When you just start the engine you aren't going to have a lot of flow because the thermostat is closed. If it's boiling you have a pressure leak somewhere as the system being under pressure is what keeps it from boiling. Every PSI raises the boiling point by a few degrees.
It sounds to me like your reservoir cap may be bad if there are no leaks elsewhere. Not as common on the plastic caps as the old but still possible. I would pressure test the cap to see how much pressure it will hold. Good luck and welcome to the forums
It sounds to me like your reservoir cap may be bad if there are no leaks elsewhere. Not as common on the plastic caps as the old but still possible. I would pressure test the cap to see how much pressure it will hold. Good luck and welcome to the forums
10-17-2013, 07:20 PM
#3
Thread Starter
Join Date: Oct 2013
Location: NM
Posts: 4
When you just start the engine you aren't going to have a lot of flow because the thermostat is closed. If it's boiling you have a pressure leak somewhere as the system being under pressure is what keeps it from boiling. Every PSI raises the boiling point by a few degrees.
It sounds to me like your reservoir cap may be bad if there are no leaks elsewhere. Not as common on the plastic caps as the old but still possible. I would pressure test the cap to see how much pressure it will hold. Good luck and welcome to the forums
It sounds to me like your reservoir cap may be bad if there are no leaks elsewhere. Not as common on the plastic caps as the old but still possible. I would pressure test the cap to see how much pressure it will hold. Good luck and welcome to the forums
10-21-2013, 07:06 AM
#5
4th Gear Member
Join Date: Aug 2008
Location: Panama City, FL
Posts: 1,214
If the temp gauge is centered, that is not an overheating indication. Might get a infrared digital thermometer and check the actual operating temps. You could have a bad head gasket allowing a compression leak into the the coolant at certain temps. This would cause fluid to overflow.
It does sound like a possible pump issue or a plugged coolant channel or hose. Possibly the lower hose is sucking closed due to its age and it has gotten soft. Could be interior of the hoses have broken down and restricting the flow.
Radiator could be plugged and restricting the flow.
It does sound like a possible pump issue or a plugged coolant channel or hose. Possibly the lower hose is sucking closed due to its age and it has gotten soft. Could be interior of the hoses have broken down and restricting the flow.
Radiator could be plugged and restricting the flow.
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