TheSloMoShow
NAXJA Forum User
- Location
- Columbus,OH
Hi all.
Yes, I picked probably the most widely used subject title for this post.
And yes, I know there is a wide variety of discussion already ongoing about system overheating.
But I think my case may be a bit more unique.
I've had my XJ for almost a year now, and for the most part no overheating problems. But this summer is reaching the 90's here in OH, and I'm recognizing some overheating issues now.
While driving (no stop-n-go), coolant stays 203-207 in the morning, and usually pegged at 210 in afternoon or early night.
But as soon as I stop, any time of day, automatically the coolant temp rises within just a minute or two.
If I've been driving for quite some time and many stop-n-go, it'll hit 225 at which point the e-fan kicks on but usually it just remains at 223-225. The e-fan doesn't help reduce the temps, just keeps it from rising ever more.
Within the past month or two, I've done the following to try and help aid the cooling system.
- Back flush (heater lines, block, radiator).
- Upgrade to ZJ fan clutch
- New T-stat (mopar) and sender unit (can't remember brand).
- 60/40 Water/glycol mix
- Added two new 10" electrical fans to front of oil cooler, behind grill. These run at all times ignition is on.
- Stant Radiator Cap (replaced about 6 months ago)
Today, while sitting in really heavy traffic for over an hour after work, I slowly watched the system rise to 237F....made me cringe. :tear:
So I pulled over as soon as I could, popped the hood to check out the condition of the system. Surprisingly, the upper radiator hose was hot but not stiff. Also, even after hitting 237 F, the overflow tank was not boiling or overflowing. As a matter of fact, it's been at the same fill mark for the past month with no movement.
So, my thinking is that either the T-stat is stuck closed or my water pump is done for....maybe the fins have eroded away. When I had the belt of last week, I played around with the pump and felt no restriction in movement so I believe the bearings to be OK, but maybe somehow still the fins have seen their end. I can't think of any other reason why it would only overheat at idle, and yet the overflow tank does not spill out any liquid. The only two system components which I haven't yet upgraded/replaced are the water pump and radiator. When I flushed the radiator out a month or so ago the discharge was crystal clear and no restriction in flow. So I'm nearly positive this isn't an issue with the radiator, but maybe is with water pump.
I was planning to buy new water pump, t-stat, lower radiator hose, and even radiator cap and replace all, but wanted your thoughts first.
2001 XJ, AW4, 170K
Yes, I picked probably the most widely used subject title for this post.
And yes, I know there is a wide variety of discussion already ongoing about system overheating.
But I think my case may be a bit more unique.
I've had my XJ for almost a year now, and for the most part no overheating problems. But this summer is reaching the 90's here in OH, and I'm recognizing some overheating issues now.
While driving (no stop-n-go), coolant stays 203-207 in the morning, and usually pegged at 210 in afternoon or early night.
But as soon as I stop, any time of day, automatically the coolant temp rises within just a minute or two.
If I've been driving for quite some time and many stop-n-go, it'll hit 225 at which point the e-fan kicks on but usually it just remains at 223-225. The e-fan doesn't help reduce the temps, just keeps it from rising ever more.
Within the past month or two, I've done the following to try and help aid the cooling system.
- Back flush (heater lines, block, radiator).
- Upgrade to ZJ fan clutch
- New T-stat (mopar) and sender unit (can't remember brand).
- 60/40 Water/glycol mix
- Added two new 10" electrical fans to front of oil cooler, behind grill. These run at all times ignition is on.
- Stant Radiator Cap (replaced about 6 months ago)
Today, while sitting in really heavy traffic for over an hour after work, I slowly watched the system rise to 237F....made me cringe. :tear:
So I pulled over as soon as I could, popped the hood to check out the condition of the system. Surprisingly, the upper radiator hose was hot but not stiff. Also, even after hitting 237 F, the overflow tank was not boiling or overflowing. As a matter of fact, it's been at the same fill mark for the past month with no movement.
So, my thinking is that either the T-stat is stuck closed or my water pump is done for....maybe the fins have eroded away. When I had the belt of last week, I played around with the pump and felt no restriction in movement so I believe the bearings to be OK, but maybe somehow still the fins have seen their end. I can't think of any other reason why it would only overheat at idle, and yet the overflow tank does not spill out any liquid. The only two system components which I haven't yet upgraded/replaced are the water pump and radiator. When I flushed the radiator out a month or so ago the discharge was crystal clear and no restriction in flow. So I'm nearly positive this isn't an issue with the radiator, but maybe is with water pump.
I was planning to buy new water pump, t-stat, lower radiator hose, and even radiator cap and replace all, but wanted your thoughts first.
2001 XJ, AW4, 170K