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Thermostat without a an air bleed valve

Slonopotam

Slonopotam

NAXJA Member #1358
Location
San Jose
Hi,

just replaced my original OEM thermostat with new Prestone and noticed Prestone does not have an air bleed valve, it was already 23:00 and could not leave the jeep disassembled on the parking lot. Am I going to have any problems without that bleed valve ?

Thank you,
Andrey
 
if you are that worried about it, you can take it out and drill a small hole in it - make your own bleed valve....

a lot of people have problems with non-OEM t-stats....
 
The biggest issue is going to be getting all the air out. Like was said, drill a very small hole in the flange. When I say small I mean a MAXIMUM of 1/16. About 1/2 way between the outside edge of the flange and the nose of the tstat, closer to the tstat. Then put it back in with the hole in the 12 O clock position.
 
If it's back together and hasn't given any grief as of yet, I'd remove the radiator cap (cold) and start it up. Let it reach full temp and the air should "burp" from the system. I usually use a jack to get the cap as high (compared to the engine) as I can by lifting the front of the vehicle.
 
RichP said:
The biggest issue is going to be getting all the air out.
Click to expand...

I tried a few 5-10 minutes shopping trips today. I could not get the engine to heat to more than 160F. It is chilly outside, around 50F. I also got new 3 row CSF.

So here are the questions:
1. Is it normal for engine not to heat up above 160F at ambient air temp 50F ?
2. If there was a huge air bubble inside the engine and the rear engine temperature sensor was not touching the coolant at all, would it report higher or lower temperature ? It is either that, or the new thermostat is stuck open.

If the answer to the first question is NO, I have to replace the stupid thing again.

Thank you,
Andrey
 
1) in 5-10 min trips, mine never gets to operating temp-- maybe 20 min.....

2) when I got my XJ it had VERY little coolant in it-- it reached the 300* mark
in less than a half mile (was reading MUCH higher than actual temp) so I'd say it will read hot with air on the sensor.
 
Shorty said:
1) in 5-10 min trips, mine never gets to operating temp-- maybe 20 min.....
Click to expand...
It looks like the needle goes quick to 160F and it just stucks there. I ran the engine at 4500RPM for a couple of minutes and the needle barely moved.

After that, I stopped and felt the upper tubes by hand - they were approximately of the same temperature, that is the thermostat was opened.

Shorty said:
so I'd say it will read hot with air on the sensor.
Click to expand...
Thanks.
 
Slonopotam said:
It looks like the needle goes quick to 160F and it just stucks there. I ran the engine at 4500RPM for a couple of minutes and the needle barely moved.

After that, I stopped and felt the upper tubes by hand - they were approximately of the same temperature, that is the thermostat was opened.


Thanks.
Click to expand...

What value thermostat did you use? If 160 - then it's probably working fine. But 190 or so is what the engine was designed for and hoses should feel pretty hot after a good drive. Maybe you got a defective thermostat? Those CFS 3 rows cool well so a good thermostat will be even that much more important.
 
One of the reasons I've always stuck with an OEM thermostat, gasket.
 
RichP said:
One of the reasons I've always stuck with an OEM thermostat, gasket.
Click to expand...

Just got OEM termostat package. Why does it have 3 different gaskets, I recognize only 1 of them ?
It is for 3 different cars ?
 
50* chilly? Why thats downright balmy around here..lol. Mt. Washington's wind chill the other days was -59.4*, they just had to get that .4 in there.
X3 on drilling a small hole in the tstat if concerned about trapped air.
 
I just swapped my thermostat for a 195 Stant Premium that doesn't have an air hole. No problems, and my XJ cools great! Warms up quickly, and the temp stays rock solid at 195 unless I'm stuck in traffic. I have yet to see it go over 210.
 
For those of you who drill bleed holes, do you just give up on pressure cap and overflow bottle ever working again or do you plug it with something? I could see tapping a hole and using some RTV and a small screw I guess but nobody ever says anything other than drilling a hole.
 
You shouldn't have to worry about the bleed hole on your open cooling system. Just let it temp cycle a few times and keep the rad topped off with fluid and make sure you have fluid in the overflow bottle. My xj heats up to about 200 in about 5-10 minutes of driving when the temps are mid 40s.

Did you over do it on the silicone when you installed the new t stat?
 
ehall said:
For those of you who drill bleed holes, do you just give up on pressure cap and overflow bottle ever working again or do you plug it with something? I could see tapping a hole and using some RTV and a small screw I guess but nobody ever says anything other than drilling a hole.
Click to expand...
Huh?:dunno:

Drilling a bleed hole in a tstat that didn't come with one has nothing to do with the pressure cap and overflow bottle...
 
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