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Unread 12-27-2007, 08:58 PM   #16
--chris--
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Actually thats what i was thinking...the replacement T-stat does not have the little hole on top with the bb behind it...should it be there?

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Unread 12-27-2007, 09:40 PM   #17
ctm
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try drilling one 1/16" hole in it on the flat part and put it back in with the hole on top.

http://groups.google.com/group/rec.a...f9ae5ca5389a18
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Unread 12-27-2007, 09:42 PM   #18
--chris--
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Thanks for the link, there is some great info there.
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Unread 12-27-2007, 09:51 PM   #19
Charlie53
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I wouldn't think that the absence of a bleed hole would make any difference if you followed the bleed procedure as described by pat8942. You should also verify the accuracy of the temperature sensor by testing its resistance in a pan of boiling water. Have you actually checked the new thermostat in a pan of boiling water as suggested by ctm? If so, and if you are inserting it with the spring inside the engine block, then it would be a wise use of your time to remove the water pump and inspect its vanes. I have seen water pumps so eroded by electrolytic corrosion that they fail to move a sufficient volume of water with a thermostat inserted but seem to be functioning properly with out a thermostat. How well did your heater function last winter? Was the output sufficient? Best of luck.
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Unread 12-28-2007, 11:10 AM   #20
--chris--
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I just bought this jeep this past summer, so winter heat is unknown to me. I would give it a 7/10 in terms on heating when its about 20 F outside.

I did check the t-stat(s) in the boiling water, and its working.

The temp gauge seems to be fairly accurate, because when the t-stat is removed it reads around 120-130 for awhile until it starts to warm up more...

I will take a look at the water pump whenever i get the time, do you think this would be an issue with a lower mileage engine? I have around 70,000 right now.

Thanks
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Unread 12-28-2007, 11:18 AM   #21
Hockey1
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definately. i had the wrong water pump on and the jeep ran great. just no heat. it never overheated. but when i wanted heat, i ran down the usual suspects, heater core, bad t-stat, hoses, plugged radiator. as soon as i put on the correct water pump, i got great heat and no overheating. the old pump didnt have enough power to circulate the coolant.
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Unread 12-29-2007, 04:15 PM   #22
--chris--
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Well i pulled the water pump today and inspected it. It is definetly not the culprit,it had no deposits/corrosion at all. It was actually very clean and smooth.

I started working on the heep this morning about 9:30, and just finished at 4:30...this included 2 runs to town and 2 random warm up breaks. I only stopped because i re assembled all the accessories except the alt (which i guess you have to pull off to get the the water pump eh?), then had to learn how to get the p.s. braket reassembled, then put all them back onto the front of the engine. I then started it (because i bought another t-stat today, this time with a little hole in the top like the factory one) and waited for leeks or overheating. Well i got a little leak coming from the t-stat housing...but nothing to make me stop the engine while testing to see if this t-stat is gonna work. I waited around about 15 minutes...checked the gauge and the damn thing just would not heat up!


Well i forgot to put the new t-stat in...i stopped working for the day once i did that, i figure thats a pretty good sign to stop if i forget something like that.

To sum it up, water pump=good. T-stat=opens when boiled and is new with breather hole like mopar piece.

If the new t-stat does not fix this tomorrow, what else could be going on here?
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Unread 12-29-2007, 06:51 PM   #23
TG Reaper
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What i'm getting here is that everything is good, accept that the t'stat will not open.If this is the case I would expect that the instalation is twisting the t'stat housing.The next time you take it apart make sure that you clean out the recess that the t'stat sits in then place the t'stat in the recess and hold it in place with a new gasket coated on both sides with a good sealer. It is very easy to bind the shaft enough that the little sucker will not open.
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Unread 12-29-2007, 08:05 PM   #24
--chris--
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Thats a pretty good idea, i never thought that it would be able to bind...

I just put in its place and, smear the sealer, and throw the gasket on there.
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Unread 12-31-2007, 12:26 PM   #25
ctm
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update ?
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Unread 01-01-2008, 11:34 AM   #26
--chris--
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I got down to business again today, and put a new t-stat from autozone (this one has the little bleeder hole on top). It runs *semi normal now! Which is better than overheating with a t-stat or no heat without a t-stat.

The *:

The temp stays right around 210, then while i am driving (with the heat on or off, it does not make a difference) the heat will start to climb...it will get to about 220 then drop rapidly back down to 160-170 and slowly build back up.

I think my rad may be to blame for this, as the top 6" of almost every row is missing its fins due to corrosion.

At least i can drive it to work now, and it also has heat. Hitching rides from employees was getting old pretty fast...lol.
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Unread 01-01-2008, 07:32 PM   #27
pat8942
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The sudden drop in temp is when the stat opens, as the radiator removes heat from the coolant it cools enough for the stat to close again until around 190 and then it opens again.
Its job is to maintain a coolant temp around 190.
It seems normal to me and the gauge could be a little off but it seems to be doing what it is supposed to do.
A new radiator does seem in order though by your description.
Quote:
Originally Posted by cheap5.0
I got down to business again today, and put a new t-stat from autozone (this one has the little bleeder hole on top). It runs *semi normal now! Which is better than overheating with a t-stat or no heat without a t-stat.

The *:

The temp stays right around 210, then while i am driving (with the heat on or off, it does not make a difference) the heat will start to climb...it will get to about 220 then drop rapidly back down to 160-170 and slowly build back up.

I think my rad may be to blame for this, as the top 6" of almost every row is missing its fins due to corrosion.

At least i can drive it to work now, and it also has heat. Hitching rides from employees was getting old pretty fast...lol.
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Unread 01-01-2008, 07:44 PM   #28
hunkajunk
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Quote:
Originally Posted by cheap5.0
The temp stays right around 210, then while i am driving (with the heat on or off, it does not make a difference) the heat will start to climb...it will get to about 220 then drop rapidly back down to 160-170 and slowly build back up.
Mine did the exact same thing for about a week after the new T-stat went in. Seems to take a while for it to settle in and behave normally again.
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Unread 01-02-2008, 12:44 AM   #29
ga_mudder
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Before I spent another dime, I would completely flush the system. I had the same issue and it turns out my heaer core was clogged. After flushing, replace the coolant and burp the system.
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Unread 01-02-2008, 01:50 AM   #30
Jesse-James
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Your heater core may need some attention. Mine did. I can now drive in a t-shirt in 10* weather.
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