Is a t-stat labeled with the temperature?
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CF Veteran
Joined: Aug 2019
Posts: 1,467
Likes: 267
From: Littleton, CO
Year: '96
Model: Cherokee (XJ)
Engine: 4.0 HO
Hey Bluejeep, just found this in the "good info threads in here" sticky:
Pertinent info underlined in red....
'96-'99: 190hp at 4600rpm, 225lbft at 3000rpm, redline 5300rpm
In 1996 engines received noise, vibration, and harshness fixes. The blocks were stiffened with extra ribbing, a main bearing brace was added, and lighter cast aluminium pistons were introduced to improve efficiency and reduce cold start piston slap. Engines also received revised camshaft timing for more low rev torque. Heads are similar except that they have no water temp port. (The OBD II system drives the guages and, only requires one port, these can be drilled and tapped for the sender used in earlier models if you're doing a head swap.)
Still waiting on my code reader BAFX OBD-II scanner to show up so I can get those temps from the air and coolant senders. UPS sucks....
Pertinent info underlined in red....
'96-'99: 190hp at 4600rpm, 225lbft at 3000rpm, redline 5300rpm
In 1996 engines received noise, vibration, and harshness fixes. The blocks were stiffened with extra ribbing, a main bearing brace was added, and lighter cast aluminium pistons were introduced to improve efficiency and reduce cold start piston slap. Engines also received revised camshaft timing for more low rev torque. Heads are similar except that they have no water temp port. (The OBD II system drives the guages and, only requires one port, these can be drilled and tapped for the sender used in earlier models if you're doing a head swap.)
Still waiting on my code reader BAFX OBD-II scanner to show up so I can get those temps from the air and coolant senders. UPS sucks....
Thread Starter
CF Veteran
Joined: Aug 2019
Posts: 1,467
Likes: 267
From: Littleton, CO
Year: '96
Model: Cherokee (XJ)
Engine: 4.0 HO
FINALLY got by OBD-II reader last night. After about 30-40 minutes of engine run time this morning, my coolant temp was reading 190°F. Intake was 145°F. I forgot to get the initial readings before I started the jeep this morning while they were both cold. I'll go for that in the morning. We had another 3" of snow last night and I was just thinking about getting the thing started, warm, and knocking the snow off the outside so I could get to work....
CF Veteran
Joined: Nov 2017
Posts: 2,478
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From: Southern Texas (former AZ & Aus)
Year: 1999
Model: Cherokee(XJ)
Engine: I6 4.0L
I wanna work on my heat issues this weekend, so I'm going to do the CLR cleanse with an air compressor and reverse flow and all that, but I also may have an issue with my thermostat in that my operating temp never gets above the 200° mark. Even in the summer and running on the highway. So I'd like to know what T-stat is in there, if its a 180°, or a 195° that's not working properly. I guess if I pull it and its not labeled, I'll just replace it anyway since I'll have the old one out. My concern is that the previous owner was extremely meticulous about the maintenance of this XJ, and it is in wonderful working order (except the blower motor switch not working on high, so I'll be replacing that as well). So I'm guessing a low temp t-stat or a failed t-stat. I'm fairly certain he said he changed the t-stat within the last couple of years, and the coolant looks amazing.
I guess the point of this is wondering if T-stats are labeled with the temperature hahaha...
I guess the point of this is wondering if T-stats are labeled with the temperature hahaha...
Thread Starter
CF Veteran
Joined: Aug 2019
Posts: 1,467
Likes: 267
From: Littleton, CO
Year: '96
Model: Cherokee (XJ)
Engine: 4.0 HO
I'm leaning towards bad t-stat, or a lower temp t-stat is in there. 190° coolant temp isnt cutting it in Denver winters... And I didnt get around to the flush yet for my in cab (warm) heating issue...Bad weather over the weekend. Still have to check my blend door as well.
One more question, since my coolant was reading 190° after 30-40 min of engine run time, what are the odds there is a 190° t-stat in there? How much warmer would the coolant be with a 190° t-stat? Will 190 t-stat bring out the normal 200-210° temps everyone else sees? If a 190 t-stat is normal and supposed to have 200-210 coolant, then I have another issue...... or else my t-stat is opening too soon or is slightly stuck open when cold.......
One more question, since my coolant was reading 190° after 30-40 min of engine run time, what are the odds there is a 190° t-stat in there? How much warmer would the coolant be with a 190° t-stat? Will 190 t-stat bring out the normal 200-210° temps everyone else sees? If a 190 t-stat is normal and supposed to have 200-210 coolant, then I have another issue...... or else my t-stat is opening too soon or is slightly stuck open when cold.......
Last edited by RockyMtn96XJ; Feb 11, 2020 at 10:49 AM.
CF Veteran
Joined: Dec 2016
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From: Long Island, New York
Year: 2001
Model: Cherokee (XJ)
Engine: 98 stroked 4.7
Lastly either visually verify no 2nd sender or pull connector off tstat sender when hot if your temp goes low then no 2nd sender.....the 96 can go either way or mix-n-match so you need to be sure...does your gauge seem to read 190....that should be fairly close to the mid hash-mark...that should be higher up than the post of your gauge from earlier
CF Veteran
Joined: Nov 2017
Posts: 2,478
Likes: 275
From: Southern Texas (former AZ & Aus)
Year: 1999
Model: Cherokee(XJ)
Engine: I6 4.0L
A side note...but on the same topic of cooling... a few months ago I decided to pull my old OEM radiator out (wasn't leaking) but planing my move now to a much hotter climate...and install a desert class unit with considerably larger diameter tubing and style for better cooling.
Now it still runs at the OEM standard op temp, because of the t-stat I have in, but the radiator itself is way more efficient than the old stock one was. Good investment if you ask me since overheating was known to be an issue at times with our old XJ's. (and really wasn't that much more than an OEM replacement one)
Now it still runs at the OEM standard op temp, because of the t-stat I have in, but the radiator itself is way more efficient than the old stock one was. Good investment if you ask me since overheating was known to be an issue at times with our old XJ's. (and really wasn't that much more than an OEM replacement one)
Thread Starter
CF Veteran
Joined: Aug 2019
Posts: 1,467
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From: Littleton, CO
Year: '96
Model: Cherokee (XJ)
Engine: 4.0 HO
Lastly either visually verify no 2nd sender or pull connector off tstat sender when hot if your temp goes low then no 2nd sender.....the 96 can go either way or mix-n-match so you need to be sure...does your gauge seem to read 190....that should be fairly close to the mid hash-mark...that should be higher up than the post of your gauge from earlier
I may just tell the wife I have to work on the jeep this weekend and go ahead and to the T-stat... I'm thinking its too low of a t-stat temp or its messed up...and figure out my blend door issue since it seems to not put the air where I want it on different settings. .
Side subject, When on the heat setting, where is the hot air supposed to be blowing from? Mine seems to only come from the floor I think, but it also comes from the dash vent...
Last edited by RockyMtn96XJ; Feb 11, 2020 at 11:09 AM.
CF Veteran
Joined: Dec 2016
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From: Long Island, New York
Year: 2001
Model: Cherokee (XJ)
Engine: 98 stroked 4.7
The temp selector only controls the air temp not where it comes from...the other dial or slider depending on what you have controls where the air comes from...I don't remember when they got rid of it...but look at the hoses where they go into the heater core at the engine side firewall...do they run directly to the tstat housing or is there a fist sized valve in the lines...that valve on older models let heat into the heater core and works with the blend door...the blend door runs on vacuum and the valve is cable controlled...does your cruise control work...runs off same vacuum line...to the beercan in front rt fender...All thermostats come in 160/180/195...no other options...If you are truly at 190 in winter...that's not bad...I run 185 and on my ski trips to Vermont I have plenty of heat...Winters almost over..wait until it warms up and see what your temps move to if at all...If you hold 190 when it warms up that would be fab
Thread Starter
CF Veteran
Joined: Aug 2019
Posts: 1,467
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From: Littleton, CO
Year: '96
Model: Cherokee (XJ)
Engine: 4.0 HO
Yeah cruise control works....
My temp was 185-190° this last summer also. or at least the gauge was in the same spot then as it is now. The picture I put up in that other thread was taken in the middle of summer after about 25 minutes of highway driving... I also saw 185-190 by reading my OBD-II reader a couple of days ago with snow all around, snow coming down, and about 30° outside... so maybe there is a 180° in there. But yeah I need to troubleshoot my HVAC and see if my heater door isnt opening all the way. That may be the only problem... If so, and I fix it and my heat comes out a lot hotter, I would stick with the 180 t-stat.
My temp was 185-190° this last summer also. or at least the gauge was in the same spot then as it is now. The picture I put up in that other thread was taken in the middle of summer after about 25 minutes of highway driving... I also saw 185-190 by reading my OBD-II reader a couple of days ago with snow all around, snow coming down, and about 30° outside... so maybe there is a 180° in there. But yeah I need to troubleshoot my HVAC and see if my heater door isnt opening all the way. That may be the only problem... If so, and I fix it and my heat comes out a lot hotter, I would stick with the 180 t-stat.
Thread Starter
CF Veteran
Joined: Aug 2019
Posts: 1,467
Likes: 267
From: Littleton, CO
Year: '96
Model: Cherokee (XJ)
Engine: 4.0 HO
So my heater control valve is working the way I think it should. So could my heat problem be due to my heater door not opening all the way or something?
CF Veteran
Joined: Nov 2017
Posts: 2,478
Likes: 275
From: Southern Texas (former AZ & Aus)
Year: 1999
Model: Cherokee(XJ)
Engine: I6 4.0L
Yeah cruise control works....
My temp was 185-190° this last summer also. or at least the gauge was in the same spot then as it is now. The picture I put up in that other thread was taken in the middle of summer after about 25 minutes of highway driving... I also saw 185-190 by reading my OBD-II reader a couple of days ago with snow all around, snow coming down, and about 30° outside... so maybe there is a 180° in there. But yeah I need to troubleshoot my HVAC and see if my heater door isnt opening all the way. That may be the only problem... If so, and I fix it and my heat comes out a lot hotter, I would stick with the 180 t-stat.
My temp was 185-190° this last summer also. or at least the gauge was in the same spot then as it is now. The picture I put up in that other thread was taken in the middle of summer after about 25 minutes of highway driving... I also saw 185-190 by reading my OBD-II reader a couple of days ago with snow all around, snow coming down, and about 30° outside... so maybe there is a 180° in there. But yeah I need to troubleshoot my HVAC and see if my heater door isnt opening all the way. That may be the only problem... If so, and I fix it and my heat comes out a lot hotter, I would stick with the 180 t-stat.
While running cooler is generally a good thing... you do want to make sure that your engine is allowed to get up to it's designed operating temp. Especially for winter time.
For example, I have new high flow desert class radiator, new water pump, t-stat and housing...full flush... etc.. the entire cooling system... And winter or middle of summer it sticks almost dead on at about 208 on the gauge with the proper temp. t-stat installed.
CF Veteran
Joined: Nov 2017
Posts: 2,478
Likes: 275
From: Southern Texas (former AZ & Aus)
Year: 1999
Model: Cherokee(XJ)
Engine: I6 4.0L
you could pull off the hoses from the t-stat housing to the heater core and do a flush on your heater core, it could be a little clogged up. just make sure you pick a reasonably warm day to do it because you've gotta do it outside and it can make a bit of a mess. Did mine last summer. If it's not leaking that could fix your heat low or no heat issue.
Thread Starter
CF Veteran
Joined: Aug 2019
Posts: 1,467
Likes: 267
From: Littleton, CO
Year: '96
Model: Cherokee (XJ)
Engine: 4.0 HO
My OBD-II reader was showing 185-190. Since the gauge only says like 100 and 210 and overheat, its hard to tell what the gauge is trying to tell me. I'm going to try the reverse flush this weekend for my heat issue.
My e-fan was kicking off and on yesterday sitting in the driveway checking my heater control valve..... weird. i had the setting on heat and maybe bi-level at some point, and A/C.
I actually have 2 threads going on right now that are talking about the same thing some how. This one and one about
My e-fan was kicking off and on yesterday sitting in the driveway checking my heater control valve..... weird. i had the setting on heat and maybe bi-level at some point, and A/C.
I actually have 2 threads going on right now that are talking about the same thing some how. This one and one about
Thread Starter
CF Veteran
Joined: Aug 2019
Posts: 1,467
Likes: 267
From: Littleton, CO
Year: '96
Model: Cherokee (XJ)
Engine: 4.0 HO
My OBD-II reader was showing 185-190. Since the gauge only says like 100 and 210 and overheat, its hard to tell what the gauge is trying to tell me. I'm going to try the reverse flush this weekend for my heat issue.
My e-fan was kicking off and on yesterday sitting in the driveway checking my heater control valve..... weird. i had the setting on heat and maybe bi-level at some point, and A/C.
I actually have 2 threads going on right now that are talking about the same thing some how. This one and one about the Stant thermostats.... I wish we could combine them!!!! or something....
My e-fan was kicking off and on yesterday sitting in the driveway checking my heater control valve..... weird. i had the setting on heat and maybe bi-level at some point, and A/C.
I actually have 2 threads going on right now that are talking about the same thing some how. This one and one about the Stant thermostats.... I wish we could combine them!!!! or something....
CF Veteran
Joined: Nov 2017
Posts: 2,478
Likes: 275
From: Southern Texas (former AZ & Aus)
Year: 1999
Model: Cherokee(XJ)
Engine: I6 4.0L
My OBD-II reader was showing 185-190. Since the gauge only says like 100 and 210 and overheat, its hard to tell what the gauge is trying to tell me. I'm going to try the reverse flush this weekend for my heat issue.
My e-fan was kicking off and on yesterday sitting in the driveway checking my heater control valve..... weird. i had the setting on heat and maybe bi-level at some point, and A/C.
I actually have 2 threads going on right now that are talking about the same thing some how. This one and one about the Stant thermostats.... I wish we could combine them!!!! or something....
My e-fan was kicking off and on yesterday sitting in the driveway checking my heater control valve..... weird. i had the setting on heat and maybe bi-level at some point, and A/C.
I actually have 2 threads going on right now that are talking about the same thing some how. This one and one about the Stant thermostats.... I wish we could combine them!!!! or something....
It should sit just below 210 and stay there.. if it starts creeping up... you may want to consider flushing your entire cooling system, could have a partial blockage somewhere.