• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

Cold snap = no heat?????

M

matttaylor1976

NAXJA Forum User
Location
Grass Valley, CA
I replaced the thermostat and waterpump about a month ago, and everything was working perfect. Then yesterday morning, heat stopped. It has been cold out, but not cold enough for the heat to stop in my opinion. I'm almost wondering if the thermostat is bad already (Napa part). Anyone have any ideas?

Edit - Sorry, should have been clearer....no heat from the heater. Temp gauge wont even get past about 120. It was blowing hot and would maintain engine temp at about 190 -200 up until yesterday morning.
 
Last edited:
if engine temp won't get to normal temps I would go with t-stat. and I have seen one (mine) go in less than 6 months of use, so 1-2 is feasable I guess.
 
coolant is full, and all air has been burped out. just really random. It's acting just like it did when i first got it, the guy i bought it from had pulled the tstat and left it out:bs:
 
How exactly do you "burp" a system?? I have an air pocket and I dont get heat unless I'm actually driving or giving the Jeep throttle. Do I just add coolant with the heater on full blast??
 
Disconnect the upper radiator hose and fill it up with coolant. Might also help to disconnect the upper heater hose from the motor and top that off too. Some people have had it start to work right after they go up a very steep hill. Possible raise the front end and run and fill it.
 
So it appears that the thermostat is fine. I got home, took the cap off the bottle, squeezed the upper radiator hose a few times and the temp started climbing to normal, put the cap back on and it stayed... i might have had an air bubble in there after all. Will post back tomorrow with results in the morning. suposta be 26 overnight, so i'll have a very good idea where i stand.
 
matttaylor1976 said:
So it appears that the thermostat is fine. I got home, took the cap off the bottle, squeezed the upper radiator hose a few times and the temp started climbing to normal, put the cap back on and it stayed... i might have had an air bubble in there after all. Will post back tomorrow with results in the morning. suposta be 26 overnight, so i'll have a very good idea where i stand.
Click to expand...

I'd give anything for 26F. This morning the temp was -24F.:shiver:
 
matttaylor1976 said:
So it appears that the thermostat is fine. I got home, took the cap off the bottle, squeezed the upper radiator hose a few times and the temp started climbing to normal, put the cap back on and it stayed... i might have had an air bubble in there after all. Will post back tomorrow with results in the morning. suposta be 26 overnight, so i'll have a very good idea where i stand.
Click to expand...

Good info........squeeze it to burp it. Hopefully simple fix.
 
I'm putting a later model t/stat housing on my 90XJ with a petcock in the sensor spot.

Not my idea, read it somewhere (maybe here?).

Should make it easy to "burp".
 
joe_peters said:
I'm putting a later model t/stat housing on my 90XJ with a petcock in the sensor spot.

Not my idea, read it somewhere (maybe here?).

Should make it easy to "burp".
Click to expand...

Not sure how that is going to help much, since you need to burp the air out from the head on the other side of the thermostat. It's easier to drill the small hole in the thermostat as 5-90 suggests, or just loosen the temp sensor to get the air out.
 
no dice....still froze my butt off on the way to work. Guess now i have to pull the freakin thermostat. This one has me baffled. stupid 4 dollar part causing all of this oh well, at least it's simple enough to fix.
 
If the air bubble is stationary in the head and never allows the thermostat to open, then drilling the thermostat and going nose-down and purging the air through the back of the head might be the best way.

As I am changing my thermostat to a higher temp one and putting on the later style housing I hope to purge the air by going nose-up and not having to mess with the sensor.

I'll let you know what happens.

:eyes:
 
Changed out 180 for new 195, with a late model modified t/housing. I modified the t/housing by tapping the sensor spot out to 3/8 pipe, installing a 3/8-1/4 pipe adapter, and installing a 1/4 pipe petcock. Installed with new SS bolts (I had to drive the long bolt out of the old t/housing with a ball peen hammer and punch!). Topped off the cooling system, fired the engine and let it warm up to an indicated 210 on the gauge with the heater on full. Shut off engine, jammed a 12" piece of 3/8 fuel hose over the end of the petcock, held the hose straight up and opened the petcock. The air rushed out, topped off reservoir with petcock open, then buttoned it up. Cost $20 for all parts. If I had broken the temp sender that would have run $10.51 at thepartsbin.com

For the rest of its life this 4.0 can be burped in under 1 minute, not including time to warm up.

Disclaimer--I didn't think of this, I read it somewhere, perhaps here?
 
so i found the problem.... a small piece of gasket managed to get stuck in the thermostat. one small frickin piece of cork managed to cause me to freeze for almost a week!!!!! All better now
 
You must log in or register to reply here.

Similar threads

U
Overheating? Quick help please.
Replies
9
Views
2K
75SV1
7
M
Oil pressure question
2
Replies
26
Views
3K
Money_Pit_Incoming
M
E
95 XJ Overheated, Shop says Head Gasket, need advice/info
Replies
18
Views
3K
Etherel15
E
G
99 temperature gauge ECT sensor issue
Replies
6
Views
1K
gba88
G
B
Jeeper needs Help !!
2
Replies
22
Views
3K
denverd1
denverd1
Back
Top