Running Hot??
#16
Thread Starter
Junior Member
Joined: Nov 2010
Posts: 66
Likes: 0
From: Centerton, AR
Year: 1995
Model: Cherokee
Engine: 4.0
Ok here is the latest news. I now have a new radiator, new fan clutch, water pump, and thermostat. Still running hot. The radiator guy said that it wasn't a gasket or cracked head. He went into about 10 min talk about why it wasn't and the tests he ran. So he is even stumped by why it just won't run at a decent temp.
Maybe i need some vents in the hood and let some of that hot air escape. I don't think that will work but I am grasping at straws at this point.
Maybe i need some vents in the hood and let some of that hot air escape. I don't think that will work but I am grasping at straws at this point.
#17
You do have a shroud on the mech fan?
While waiting for the time and money to do my cooling system refurb I raised the rear of my hood 1"+ to let some heat out. It did keep it a hair below the 210 mark and the same at the max temp I was seeing. Really wasn't worth it but I felt better. LOL I've lowered it since the refurb. My point is that venting the heat from under the hood isn't going to solve what I feel is another problem besides a high temp/overheating problem. And that's the temp spread from the normal op temp to the max temp you should see. Since the refurb my norm is 195 and max (hot air temp,A/C on,pulling a long steep grade) is just off the 210 mark to the right. Use to be 210 up to the beginning of the red.
While waiting for the time and money to do my cooling system refurb I raised the rear of my hood 1"+ to let some heat out. It did keep it a hair below the 210 mark and the same at the max temp I was seeing. Really wasn't worth it but I felt better. LOL I've lowered it since the refurb. My point is that venting the heat from under the hood isn't going to solve what I feel is another problem besides a high temp/overheating problem. And that's the temp spread from the normal op temp to the max temp you should see. Since the refurb my norm is 195 and max (hot air temp,A/C on,pulling a long steep grade) is just off the 210 mark to the right. Use to be 210 up to the beginning of the red.
#18
Thread Starter
Junior Member
Joined: Nov 2010
Posts: 66
Likes: 0
From: Centerton, AR
Year: 1995
Model: Cherokee
Engine: 4.0
You do have a shroud on the mech fan?
While waiting for the time and money to do my cooling system refurb I raised the rear of my hood 1"+ to let some heat out. It did keep it a hair below the 210 mark and the same at the max temp I was seeing. Really wasn't worth it but I felt better. LOL I've lowered it since the refurb. My point is that venting the heat from under the hood isn't going to solve what I feel is another problem besides a high temp/overheating problem. And that's the temp spread from the normal op temp to the max temp you should see. Since the refurb my norm is 195 and max (hot air temp,A/C on,pulling a long steep grade) is just off the 210 mark to the right. Use to be 210 up to the beginning of the red.
While waiting for the time and money to do my cooling system refurb I raised the rear of my hood 1"+ to let some heat out. It did keep it a hair below the 210 mark and the same at the max temp I was seeing. Really wasn't worth it but I felt better. LOL I've lowered it since the refurb. My point is that venting the heat from under the hood isn't going to solve what I feel is another problem besides a high temp/overheating problem. And that's the temp spread from the normal op temp to the max temp you should see. Since the refurb my norm is 195 and max (hot air temp,A/C on,pulling a long steep grade) is just off the 210 mark to the right. Use to be 210 up to the beginning of the red.
#19
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
What does it run while on interstate? Does coolant boil into the bottle? Verified gauge temp with a infrared temp gun? As mentioned, fan shrouds in place/intact?
#21
Junior Member
Joined: Jan 2012
Posts: 81
Likes: 0
From: St Louis Area
Year: 1999
Model: Cherokee
Engine: 4.0
engine overheat
I had the same issue with another car. The machanic suggested replacing the fan at $400.00 +. I did a little research, replaced a fan relay for $13.00, and haven't had another issue.
#22
Thread Starter
Junior Member
Joined: Nov 2010
Posts: 66
Likes: 0
From: Centerton, AR
Year: 1995
Model: Cherokee
Engine: 4.0
It stays a little below 210 when on the interstate. I really don't see it boil into the bottle. Yeah the radiator shop tested the gauge to make sure it was correct. Fan shroud was the first thing I put on.
#23
Thread Starter
Junior Member
Joined: Nov 2010
Posts: 66
Likes: 0
From: Centerton, AR
Year: 1995
Model: Cherokee
Engine: 4.0
#24
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
#25
I'm in the same boat as you are twm3000. I have 2 identical '96 Cherokees with the 4.0 engine. They're both RHD Jeeps that were made here in the US for sale in the Japanese market. I re-imported them and use them on a rural mail route. A few weeks ago, I started smelling anti freeze on the route. Over several days, I checked and double checked but could see no visible leaks. My gauge reads in Celcius, so my marks are 40, 100 and 120...which correspond to yours. Normally, my needle is always at or just below 100 (212 F). It has been hot all summer here, so I've been running the A/C on the route quite often. When I started to notice the smell, I noticed the gauge was almost always between 100 and 120 (212 and 248 F). One day it creeped very close to the red (120) and suddenly I had steam pouring out from under the hood. The plastic flushing tee I had put in last fall was the culprit, as the heat literally blew the plastic screw-on cap right off the tee. I replaced that whole hose with a solid piece of new heater hose and took it back on the route the next day. The gauge almost always runs between 100 and 120 now, with or without the A/C on, but here's the unique thing: if the ambient outside temperature is 90 to 100, the gauge usually goes right up to the red until I get to a part of the route where I'm moving at a good clip to flow more air through the radiator. If the ambient temp. is around 80 or lower, the needle seems to stay right at 100 (212 F). I pressure tested the radiator and cooling system the other night and it didn't seem like there was any leak-down in pressure. Today, it was about 95 F outside and I took it out for a ride. The needle got barely past 100 but I could still smell anti freeze. When I got home after about a 15 minute drive, the hood and hood support rod were literally so hot that I couldn't hold on to either of them without grabbing a rag first. I replaced the radiator cap and both the electric and mechanical fans are always turning. As for the fan clutch, I'm not really sure I understand what I'm supposed to be looking for. If it keeps spinning after the engine is off, that means it is bad? Anyway, I'm not sure what's going on here. My other Jeep's temp. needle never even gets to 100 (212 F) even on the hottest days with the A/C running for the whole route. Any ideas or suggestions are welcomed and appreciated! Oh...the only other thing that I've noticed lately is that my catalytic converter is making a noise that sounds like marbles in a coffee can. This is most often at idle and the sound goes away under acceleration. Any chance that a bad or blocked converter can make an engine overheat? (Water pump has NOT been replaced...both upper and lower radiator hoses are extremely hot when the engine is at operating temperature.)
#26
CF Veteran
Joined: Nov 2009
Posts: 8,172
Likes: 17
From: The Republic of TEXAS
Year: 1998
Model: Cherokee
Engine: 4.0L HO
Best way to test the fan clutch is, ask yourself how old it is (as well as other cooling system components), if u don't know, spend +/-#35 for a new fan clutch. With regard to RHD (or postal XJs), I believe there is a 2 row heavy duty aluminum core radiator for RHD postal units. Smelling antifreeze and not seeing a leak could be the heater core leaking. A blocked converter can definitely cause an overheat but most likely a coolant overheat is from cooling system neglect/poor maintenance.
Last edited by djb383; 08-04-2012 at 07:59 PM.
#27
Thread Starter
Junior Member
Joined: Nov 2010
Posts: 66
Likes: 0
From: Centerton, AR
Year: 1995
Model: Cherokee
Engine: 4.0
#28
Thread Starter
Junior Member
Joined: Nov 2010
Posts: 66
Likes: 0
From: Centerton, AR
Year: 1995
Model: Cherokee
Engine: 4.0
I'm in the same boat as you are twm3000. I have 2 identical '96 Cherokees with the 4.0 engine. They're both RHD Jeeps that were made here in the US for sale in the Japanese market. I re-imported them and use them on a rural mail route. A few weeks ago, I started smelling anti freeze on the route. Over several days, I checked and double checked but could see no visible leaks. My gauge reads in Celcius, so my marks are 40, 100 and 120...which correspond to yours. Normally, my needle is always at or just below 100 (212 F). It has been hot all summer here, so I've been running the A/C on the route quite often. When I started to notice the smell, I noticed the gauge was almost always between 100 and 120 (212 and 248 F). One day it creeped very close to the red (120) and suddenly I had steam pouring out from under the hood. The plastic flushing tee I had put in last fall was the culprit, as the heat literally blew the plastic screw-on cap right off the tee. I replaced that whole hose with a solid piece of new heater hose and took it back on the route the next day. The gauge almost always runs between 100 and 120 now, with or without the A/C on, but here's the unique thing: if the ambient outside temperature is 90 to 100, the gauge usually goes right up to the red until I get to a part of the route where I'm moving at a good clip to flow more air through the radiator. If the ambient temp. is around 80 or lower, the needle seems to stay right at 100 (212 F). I pressure tested the radiator and cooling system the other night and it didn't seem like there was any leak-down in pressure. Today, it was about 95 F outside and I took it out for a ride. The needle got barely past 100 but I could still smell anti freeze. When I got home after about a 15 minute drive, the hood and hood support rod were literally so hot that I couldn't hold on to either of them without grabbing a rag first. I replaced the radiator cap and both the electric and mechanical fans are always turning. As for the fan clutch, I'm not really sure I understand what I'm supposed to be looking for. If it keeps spinning after the engine is off, that means it is bad? Anyway, I'm not sure what's going on here. My other Jeep's temp. needle never even gets to 100 (212 F) even on the hottest days with the A/C running for the whole route. Any ideas or suggestions are welcomed and appreciated! Oh...the only other thing that I've noticed lately is that my catalytic converter is making a noise that sounds like marbles in a coffee can. This is most often at idle and the sound goes away under acceleration. Any chance that a bad or blocked converter can make an engine overheat? (Water pump has NOT been replaced...both upper and lower radiator hoses are extremely hot when the engine is at operating temperature.)
#30
Senior Member
Joined: Dec 2011
Posts: 669
Likes: 0
From: Central Arkansas
Year: 1996
Model: Cherokee
Engine: 4.0L
Originally Posted by spudzy
I'm in the same boat as you are twm3000. I have 2 identical '96 Cherokees with the 4.0 engine. They're both RHD Jeeps that were made here in the US for sale in the Japanese market. I re-imported them and use them on a rural mail route. A few weeks ago, I started smelling anti freeze on the route. Over several days, I checked and double checked but could see no visible leaks. My gauge reads in Celcius, so my marks are 40, 100 and 120...which correspond to yours. Normally, my needle is always at or just below 100 (212 F). It has been hot all summer here, so I've been running the A/C on the route quite often. When I started to notice the smell, I noticed the gauge was almost always between 100 and 120 (212 and 248 F). One day it creeped very close to the red (120) and suddenly I had steam pouring out from under the hood. The plastic flushing tee I had put in last fall was the culprit, as the heat literally blew the plastic screw-on cap right off the tee. I replaced that whole hose with a solid piece of new heater hose and took it back on the route the next day. The gauge almost always runs between 100 and 120 now, with or without the A/C on, but here's the unique thing: if the ambient outside temperature is 90 to 100, the gauge usually goes right up to the red until I get to a part of the route where I'm moving at a good clip to flow more air through the radiator. If the ambient temp. is around 80 or lower, the needle seems to stay right at 100 (212 F). I pressure tested the radiator and cooling system the other night and it didn't seem like there was any leak-down in pressure. Today, it was about 95 F outside and I took it out for a ride. The needle got barely past 100 but I could still smell anti freeze. When I got home after about a 15 minute drive, the hood and hood support rod were literally so hot that I couldn't hold on to either of them without grabbing a rag first. I replaced the radiator cap and both the electric and mechanical fans are always turning. As for the fan clutch, I'm not really sure I understand what I'm supposed to be looking for. If it keeps spinning after the engine is off, that means it is bad? Anyway, I'm not sure what's going on here. My other Jeep's temp. needle never even gets to 100 (212 F) even on the hottest days with the A/C running for the whole route. Any ideas or suggestions are welcomed and appreciated! Oh...the only other thing that I've noticed lately is that my catalytic converter is making a noise that sounds like marbles in a coffee can. This is most often at idle and the sound goes away under acceleration. Any chance that a bad or blocked converter can make an engine overheat? (Water pump has NOT been replaced...both upper and lower radiator hoses are extremely hot when the engine is at operating temperature.)