Heating up-Idle (please help)
07-30-2014, 05:56 PM
#31
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Year: 2000
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I stole that photo also. To be honest, I took it from Google, and I didn't pay attention to where Google found it. I should have given credit it to whoever took it, because it's a perfect illustration. That was bad netiquette on my part.
Unfortunately that does look like the water pump is shot. The good news is that they're not that expensive, nor are the difficult to change.
Where did I say that water pumps create pressure?
Heat creates pressure. The coolant system is pressurized, with a relief valve in the form of the radiator cap. When the system is cold, the system shouldn't have any pressure in it. When the coolant is heated, however, the system becomes pressurized up to the rating on the radiator cap. It's designed to hold pressure because applying pressure to a liquid raises its boiling temperature. The system is more efficient under pressure because the water cannot boil out of the coolant.
If the water pump has died and is leaking coolant from the weep hole, the system is losing pressure from the weep hole so that the radiator cap is no longer regulating the pressure. That causes the coolant to boil at a lower temperature, leading to evaporation that leaves that horrible red mud behind. You also end up with gas pockets in your system.
I suggested she drive it because she just got the lower hose replaced at Firestone, so all that crap would have been cleaned off. You're right that it should show up fairly quickly if not immediately, but she needs to be able to be sure, and we don't know how fast it's leaking or how much she drove it after the oil change.
Unfortunately that does look like the water pump is shot. The good news is that they're not that expensive, nor are the difficult to change.
Heat creates pressure. The coolant system is pressurized, with a relief valve in the form of the radiator cap. When the system is cold, the system shouldn't have any pressure in it. When the coolant is heated, however, the system becomes pressurized up to the rating on the radiator cap. It's designed to hold pressure because applying pressure to a liquid raises its boiling temperature. The system is more efficient under pressure because the water cannot boil out of the coolant.
If the water pump has died and is leaking coolant from the weep hole, the system is losing pressure from the weep hole so that the radiator cap is no longer regulating the pressure. That causes the coolant to boil at a lower temperature, leading to evaporation that leaves that horrible red mud behind. You also end up with gas pockets in your system.
I suggested she drive it because she just got the lower hose replaced at Firestone, so all that crap would have been cleaned off. You're right that it should show up fairly quickly if not immediately, but she needs to be able to be sure, and we don't know how fast it's leaking or how much she drove it after the oil change.
07-30-2014, 06:06 PM
#33
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People use my photos all the time. No worries. Netiquitte don't matter.
Looks like she's on the right track to a fix. Begin with a water pump and fan clutch.
Looks like she's on the right track to a fix. Begin with a water pump and fan clutch.
07-30-2014, 10:19 PM
#34
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I stole that photo also. To be honest, I took it from Google, and I didn't pay attention to where Google found it. I should have given credit it to whoever took it, because it's a perfect illustration. That was bad netiquette on my part. Unfortunately that does look like the water pump is shot. The good news is that they're not that expensive, nor are the difficult to change. Where did I say that water pumps create pressure? Heat creates pressure. The coolant system is pressurized, with a relief valve in the form of the radiator cap. When the system is cold, the system shouldn't have any pressure in it. When the coolant is heated, however, the system becomes pressurized up to the rating on the radiator cap. It's designed to hold pressure because applying pressure to a liquid raises its boiling temperature. The system is more efficient under pressure because the water cannot boil out of the coolant. If the water pump has died and is leaking coolant from the weep hole, the system is losing pressure from the weep hole so that the radiator cap is no longer regulating the pressure. That causes the coolant to boil at a lower temperature, leading to evaporation that leaves that horrible red mud behind. You also end up with gas pockets in your system. I suggested she drive it because she just got the lower hose replaced at Firestone, so all that crap would have been cleaned off. You're right that it should show up fairly quickly if not immediately, but she needs to be able to be sure, and we don't know how fast it's leaking or how much she drove it after the oil change.
Went to Firestone to get oil changed. Asked tech to check the lower hose for a leak, he said that the hose and clamps were old but NO leak. I did NOT have them replaced.
Now I drove around today for 20 minutes and checked the lower hose (please see pics on page 2). Looked like there was a small leak at one of the clamps (lower hose). I will be replacing it.
I prefer to start small first.
Next, I am not losing that much antifreeze, about a half cup in the last 3 months. This has been going on for about a year but I changed out a few hoses because of leaks and the heater core valve so I wasn't sure what was going on.
Now, the problem: Coolant gauge is getting hot in idle (regularly) and now sometimes while coasting (foot off the gas and when parking) if I've been driving a while. I haven't gotten to the red but very close to it. When I'm on the highway, it's all good, like this pic, unless I hit traffic.
One step at a time, starting small, please help...thanks...
Fan:
Appears to be good. It's spinning as the car heats up.
A/C:
Works great
What's the verdict?
Last edited by WomanNeedsJeepExpertise; 07-30-2014 at 10:35 PM.
07-30-2014, 10:45 PM
#35
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Change the fan clutch now and see what happens. can you see the factory part numbers on the radiator through the oblong hole in the radiator support?
07-31-2014, 04:06 AM
#36
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Extrashakey: I don't believe that you would actually be able to measure "pressure loss" at the weep hole. If there is any, it would be negligible.
The weep hole is on the non-pressurized side of the system. Fluid doesn't squirt out of there.
Therefore, I stand by my comment about your linking failing water pump, weep hole drip, and pressure loss.
To the OP: Your latest pic shows the temp gauge to be higher than normal for highway driving, at least as compared to my '92. In addition, your mechanical fan will spin even with a bad or weak fan clutch. The key question is, is it locking up like it should to bring more air through the radiator?
The weep hole is on the non-pressurized side of the system. Fluid doesn't squirt out of there.
Therefore, I stand by my comment about your linking failing water pump, weep hole drip, and pressure loss.
To the OP: Your latest pic shows the temp gauge to be higher than normal for highway driving, at least as compared to my '92. In addition, your mechanical fan will spin even with a bad or weak fan clutch. The key question is, is it locking up like it should to bring more air through the radiator?
Last edited by Firestorm500; 07-31-2014 at 04:14 AM.
07-31-2014, 04:48 AM
#37
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OP, time to get things done now: starting small as a credo is nice, but "small" stuff won't always fix the issue. If small equals easy repairs, that's fine. your problem is not complicated. in fact pretty straight forward and so are the solutions that most likely will fix your problem.
Your AC working fine is not related to your overheating issue. The only thing might be that having the AC on will increase your temp, and shutting it off might bring it down somewhat.
Several experienced members here now have suggested to replace your water pump and viscous fan. Now, go for it! The only extra thing to do down there, since you will drain coolant anyway and have to detach one end of it, is to replace the bottom radiator hose and, like I already stated before,...be done with it down there.
Give it a go.
Your AC working fine is not related to your overheating issue. The only thing might be that having the AC on will increase your temp, and shutting it off might bring it down somewhat.
Several experienced members here now have suggested to replace your water pump and viscous fan. Now, go for it! The only extra thing to do down there, since you will drain coolant anyway and have to detach one end of it, is to replace the bottom radiator hose and, like I already stated before,...be done with it down there.
Give it a go.
07-31-2014, 06:53 AM
#39
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OP, time to get things done now: starting small as a credo is nice, but "small" stuff won't always fix the issue. If small equals easy repairs, that's fine. your problem is not complicated. in fact pretty straight forward and so are the solutions that most likely will fix your problem.
Your AC working fine is not related to your overheating issue. The only thing might be that having the AC on will increase your temp, and shutting it off might bring it down somewhat.
Several experienced members here now have suggested to replace your water pump and viscous fan. Now, go for it! The only extra thing to do down there, since you will drain coolant anyway and have to detach one end of it, is to replace the bottom radiator hose and, like I already stated before,...be done with it down there.
Give it a go.
Your AC working fine is not related to your overheating issue. The only thing might be that having the AC on will increase your temp, and shutting it off might bring it down somewhat.
Several experienced members here now have suggested to replace your water pump and viscous fan. Now, go for it! The only extra thing to do down there, since you will drain coolant anyway and have to detach one end of it, is to replace the bottom radiator hose and, like I already stated before,...be done with it down there.
Give it a go.
07-31-2014, 06:55 AM
#40
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Year: 1990
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Extrashakey: I don't believe that you would actually be able to measure "pressure loss" at the weep hole. If there is any, it would be negligible.
The weep hole is on the non-pressurized side of the system. Fluid doesn't squirt out of there.
Therefore, I stand by my comment about your linking failing water pump, weep hole drip, and pressure loss.
To the OP: Your latest pic shows the temp gauge to be higher than normal for highway driving, at least as compared to my '92. In addition, your mechanical fan will spin even with a bad or weak fan clutch. The key question is, is it locking up like it should to bring more air through the radiator?
The weep hole is on the non-pressurized side of the system. Fluid doesn't squirt out of there.
Therefore, I stand by my comment about your linking failing water pump, weep hole drip, and pressure loss.
To the OP: Your latest pic shows the temp gauge to be higher than normal for highway driving, at least as compared to my '92. In addition, your mechanical fan will spin even with a bad or weak fan clutch. The key question is, is it locking up like it should to bring more air through the radiator?
Anyway, if you want to discuss thermodynamics and pressures, how about
starting a thread in Chat? Roler and a few others have summarized things nicely for the original poster.
07-31-2014, 07:36 AM
#41
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As I mentioned above, check the weep hole on the water pump. The weep hole on mine is on the underside of the pump where it's impossible to see from the top. If the water pump fails, coolant will leak out of that weep hole and run down the hose, making it look like there's a hose leak. Get some air swirling up in there out on the road, and you can't tell where the hell it's coming from. The same thing can happen if there's a leak between the water pump and the block, in which case your water pump may be fine, but you're still chasing a phantom. If yours is on the bottom like mine, before you go pulling off radiator hoses and replacing clamps, I would suggest that you get under the Jeep with a flashlight to see if you can get a look at the weep hole from the bottom. If you can't see it from the floor, get one of those mechanic's mirrors like this or this and take a look from the top. I'm not saying you shouldn't replace your hoses, but doing so won't do you any good if that's not the source of your leak. If it's coming from your water pump, it needs to be replaced, and there's no point in replacing a hose that isn't leaking only to take it off again later when you replace the water pump. Likewise if the pump is good but the seal against the block is shot.
07-31-2014, 07:39 AM
#42
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There's a great photo in Post #17, looking up at the area where the lower radiator hose connects to the water pump.
07-31-2014, 07:44 AM
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The pic I took almost identical but I still couldn't see a weephole under there.
Questions: are the viscous fan and fan clutch the same?
I need to know what parts I'm buying, where from and I really need instructions please.
Questions: are the viscous fan and fan clutch the same?
I need to know what parts I'm buying, where from and I really need instructions please.
07-31-2014, 07:47 AM
#44
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07-31-2014, 07:57 AM
#45
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Viscous fan and viscous fan clutch are used for the same item. You just need the "clutch" part, the fins/blades you can take off and put on the new part.
Not sure if you meant Cruiser, me or somebody else: more than happy to provide instructions, but not sure if my RHD is the same setup as yours. It would essentially be the same.
For things like this, and any future repairs/maintenance, it's worth it to get your hands on a factory service manual. Step-by-step instructions.
Not sure if you meant Cruiser, me or somebody else: more than happy to provide instructions, but not sure if my RHD is the same setup as yours. It would essentially be the same.
For things like this, and any future repairs/maintenance, it's worth it to get your hands on a factory service manual. Step-by-step instructions.