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Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go hereXJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.
I recently replaced the water pump, t-stat, t-stat housing and hoses and did a flush using prestone. Directions said to pour that in, fill with distilled water and drive around for a few days but the Jeep quickly overheated every time I drove. I'm not happy with the results of the prestone so I bought Thermocure and the directions say the same thing but I'm worried. Can I just pour the thermocure in with my regular coolant and drive it around for the week?
Yes, just dump it in to the empty and flushed system, fill with distilled water, and drive around for a few days. Same as with the Prestone flush. It's definitely a warm-weather activity, since you're not running anti-freeze.
It sounds like you have air trapped in the system, which is causing your overheating problem, not the flush solution. Try parking facing uphill while you run the engine up to temp to open the t-stat and bleed air. Squeeze the radiator hoses, as that sometimes helps burp air. Also, those funnel kits that help fill and burp the system make life a lot easier.
No, don’t mix Thermocure with coolant. It won’t work right. Drain the coolant, flush with distilled water, then add Thermocure and top off with distilled water only no coolant. Run it for the week as directed, then flush again and add fresh coolant. The overheating means your system is still clogged or has air pockets, so check that too.
Yes, just dump it in to the empty and flushed system, fill with distilled water, and drive around for a few days. Same as with the Prestone flush. It's definitely a warm-weather activity, since you're not running anti-freeze.
It sounds like you have air trapped in the system, which is causing your overheating problem, not the flush solution. Try parking facing uphill while you run the engine up to temp to open the t-stat and bleed air. Squeeze the radiator hoses, as that sometimes helps burp air. Also, those funnel kits that help fill and burp the system make life a lot easier.
Not sure you understood the question. When I used the Prestone with just water, she overheated in under 5 minutes each & every time because water boils at 180°. I'm asking if I can run the thermocure with the coolant (50/50) that's in the motor now so it doesn't boil the water??
As for the other tips, I used them all. Squeezing hoses, parking uphill and burping the system with that huge funnel. Ran it for an hour in idle then left the system open for 5-6 hours to let air out and coolant in. However the overheating issue I have now is only after driving for a while in humid weather. I do agree that it feels like air is still trapped somewhere. Maybe I'll find a bigger hill! Lmao
I should also add that I'm running a mishimoto aluminum radiator, silicone hoses, bored out T-stat housing, 185 Stat, high flow water pump and I have an e-fan override switch; so I should not be getting close to 210°-215°!
When driving around town, she stays put at 185°-190° the entire time unless it's over 25 min.
No, don’t mix Thermocure with coolant. It won’t work right. Drain the coolant, flush with distilled water, then add Thermocure and top off with distilled water only no coolant. Run it for the week as directed, then flush again and add fresh coolant. The overheating means your system is still clogged or has air pockets, so check that too.
would you know why the Prestone flush let the distilled water boil over then?
Not sure you understood the question. When I used the Prestone with just water, she overheated in under 5 minutes each & every time because water boils at 180°. I'm asking if I can run the thermocure with the coolant (50/50) that's in the motor now so it doesn't boil the water??
As for the other tips, I used them all. Squeezing hoses, parking uphill and burping the system with that huge funnel. Ran it for an hour in idle then left the system open for 5-6 hours to let air out and coolant in. However the overheating issue I have now is only after driving for a while in humid weather. I do agree that it feels like air is still trapped somewhere. Maybe I'll find a bigger hill! Lmao
Setting aside the fact that water boils at 212° (actually higher in a pressurized cooling system), you've somehow got air in the system. When you let it cool, keep the radiator cap on. Otherwise it'll just pull air in as it cools rather than suck coolant back in from the overflow tank like it should. Try that and see what happens.
One more thing: Does your thermostat have the little hole it it to let air out? If so, is it correctly mounted so the hole is at the top?
Setting aside the fact that water boils at 212° (actually higher in a pressurized cooling system), you've somehow got air in the system. When you let it cool, keep the radiator cap on. Otherwise it'll just pull air in as it cools rather than suck coolant back in from the overflow tank like it should. Try that and see what happens.
One more thing: Does your thermostat have the little hole it it to let air out? If so, is it correctly mounted so the hole is at the top?
This stat doesn't however I'm swapping in one that does have the hole. Thanks for the tip, I'm gonna go ahead and give it a go.
Were you having the same problem before you changed everything? Those chemicals are all snake oil. If it doesn't operate correctly with coolant and water something else is wrong. Remove your hoses and flush everything out with water. Double check your thermostat. Might have a bad one.
Were you having the same problem before you changed everything? Those chemicals are all snake oil. If it doesn't operate correctly with coolant and water something else is wrong. Remove your hoses and flush everything out with water. Double check your thermostat. Might have a bad one.
I did 5 flushes after using the prestone unit it came out clear as water. Aand that's the weird part. I'm 1 step ahead of you there as I'm putting a 2nd t-stat in. The thing that sucks is I'm taking the new Mishimoto t-stat out and putting in a Stant t-stat.
( yes I know Stant got bought out, lol)
Why did you replace everything? Problem or precaution? What about that clutch fan?
Was time to do a coolant flush and as I'm planning to do so, the water pump went. So now I have everything for the flush, BUTI now have to wait for a water pump. Picked up a flow cooler and figured I'd throw in a $400 dollar Mishimoto radiator! 🤣🤣🤣
Clutch is new stock unit as I can't fit the heavy duty with the new radiator.
I have a Hayden unit to put in because it does show some signs of wear.
Using Thermocure
