97 Overheating Issues
07-23-2019, 07:00 PM
#1
97 Overheating Issues
My 97 started getting warm and purging out the surge tank. I have since changed the thermostat, water pump, radiator, and surge tank and it continues to overheat and even threw itself into a loss power mode I assume is to protect the motor. I've noticed the left fan isn't coming on and the back-pressure on the right side doesn't seem as strong as it should be. No check engine light or trouble codes. Any ideas or suggestions?
Last edited by NathanKellie Bradway; 07-23-2019 at 08:57 PM.
07-24-2019, 02:00 PM
#2
Unclear if this is happening at slow speed/stopped or at higher speeds.
If at slow speed, a fan problem will definitely cause problems. I have had to replace the right fan motor twice.
Both fans should come on low speed at 226 deg and both high speed at 235 deg. Is your right fan not coming on high speed? I have pretty much convinced myself that no single relay, etc., will affect only one fanson low speed, but there are separate relays for high speed. Search this forum for wiring diagrams.
Many posts on this forum about the radiator exterior getting blocked by paper, plastic, etc., but good old fashioned dirt will do it too.
Particularly if there are problems at highway speeds, it could be something else entirely. If you have previously replaced things like the surge tank, a pressure test might be in order. A sniffer test for head gasket leakage might be in order, also.
I am not in anyway an expert mechanic, just a fellow owner that has dealt with some of these problems. I just had the right fan motor replaced on my 2002 and the radiator exterior cleaned.
If at slow speed, a fan problem will definitely cause problems. I have had to replace the right fan motor twice.
Both fans should come on low speed at 226 deg and both high speed at 235 deg. Is your right fan not coming on high speed? I have pretty much convinced myself that no single relay, etc., will affect only one fanson low speed, but there are separate relays for high speed. Search this forum for wiring diagrams.
Many posts on this forum about the radiator exterior getting blocked by paper, plastic, etc., but good old fashioned dirt will do it too.
Particularly if there are problems at highway speeds, it could be something else entirely. If you have previously replaced things like the surge tank, a pressure test might be in order. A sniffer test for head gasket leakage might be in order, also.
I am not in anyway an expert mechanic, just a fellow owner that has dealt with some of these problems. I just had the right fan motor replaced on my 2002 and the radiator exterior cleaned.
07-24-2019, 04:06 PM
#5
Unclear if this is happening at slow speed/stopped or at higher speeds.
If at slow speed, a fan problem will definitely cause problems. I have had to replace the right fan motor twice.
Both fans should come on low speed at 226 deg and both high speed at 235 deg. Is your right fan not coming on high speed? I have pretty much convinced myself that no single relay, etc., will affect only one fanson low speed, but there are separate relays for high speed. Search this forum for wiring diagrams.
Many posts on this forum about the radiator exterior getting blocked by paper, plastic, etc., but good old fashioned dirt will do it too.
Particularly if there are problems at highway speeds, it could be something else entirely. If you have previously replaced things like the surge tank, a pressure test might be in order. A sniffer test for head gasket leakage might be in order, also.
I am not in anyway an expert mechanic, just a fellow owner that has dealt with some of these problems. I just had the right fan motor replaced on my 2002 and the radiator exterior cleaned.
If at slow speed, a fan problem will definitely cause problems. I have had to replace the right fan motor twice.
Both fans should come on low speed at 226 deg and both high speed at 235 deg. Is your right fan not coming on high speed? I have pretty much convinced myself that no single relay, etc., will affect only one fanson low speed, but there are separate relays for high speed. Search this forum for wiring diagrams.
Many posts on this forum about the radiator exterior getting blocked by paper, plastic, etc., but good old fashioned dirt will do it too.
Particularly if there are problems at highway speeds, it could be something else entirely. If you have previously replaced things like the surge tank, a pressure test might be in order. A sniffer test for head gasket leakage might be in order, also.
I am not in anyway an expert mechanic, just a fellow owner that has dealt with some of these problems. I just had the right fan motor replaced on my 2002 and the radiator exterior cleaned.
07-25-2019, 01:43 AM
#6
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NathanKellie Bradway (07-25-2019)
07-25-2019, 11:07 AM
#8
Melting Slicks
Won't hurt to put a 18 lbs pressure cap, but your overheating is most likely being caused by your left fan not coming on, you most likely will have to replace it.
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NathanKellie Bradway (07-25-2019)
07-25-2019, 11:31 AM
#9
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Sounds to me like you have an air flow issue but it is more than a FAN issue. Your car is 22 years old. Think of all the dirt and dust that has gone through the radiator fins.
Pop off the air bridge and remove the plastic cover over the radiator and condenser. There is a 1" space between the rad and condenser. It gets clogged up with dirt and grass. Back flush the fins with a garden hose on full stream and see all the crap that comes out.
Look up under the front facia at the opening for the radiator and see if it has trash in it.
Bill
Pop off the air bridge and remove the plastic cover over the radiator and condenser. There is a 1" space between the rad and condenser. It gets clogged up with dirt and grass. Back flush the fins with a garden hose on full stream and see all the crap that comes out.
Look up under the front facia at the opening for the radiator and see if it has trash in it.
Bill
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NathanKellie Bradway (07-25-2019)
07-25-2019, 11:05 PM
#10
Sounds to me like you have an air flow issue but it is more than a FAN issue. Your car is 22 years old. Think of all the dirt and dust that has gone through the radiator fins.
Pop off the air bridge and remove the plastic cover over the radiator and condenser. There is a 1" space between the rad and condenser. It gets clogged up with dirt and grass. Back flush the fins with a garden hose on full stream and see all the crap that comes out.
Look up under the front facia at the opening for the radiator and see if it has trash in it.
Bill
Pop off the air bridge and remove the plastic cover over the radiator and condenser. There is a 1" space between the rad and condenser. It gets clogged up with dirt and grass. Back flush the fins with a garden hose on full stream and see all the crap that comes out.
Look up under the front facia at the opening for the radiator and see if it has trash in it.
Bill
07-26-2019, 04:26 PM
#11
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Did you clean the fins of the AC Condenser?
Did you BURP the block to insure that all the trapped air is out of the cooling passages?
Did you BURP the block to insure that all the trapped air is out of the cooling passages?
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NathanKellie Bradway (07-29-2019)
07-29-2019, 02:02 AM
#12
07-29-2019, 05:32 PM
#13
Melting Slicks
Wanting to inquire if your cars overheating is occurring while idling, stop and go traffic, of out on the highway? One thing to try is to go for a drive out on the highway and see if it starts overheating, once the car goes over 35 mph the fans are shut off so as not to impede air flow, that will determine if your cooling system is working correctly. If overheating occurs in stop and go city driving or just idling then that left fan not coming on is causing 50% reduction in air flow and hence 50% loss of cooling. Hope this helps.