Need Help

[rodman467]

I have an 1984 Jeep CJ7, it overheated 2 day ago, I replace the Thermostat, the Radiator and the Water Pump. Now when I start the jeep, it will idle fine and the temp will slowly move up until the jeep overheats. I took the radiator cap off once it was cooled down and started the jeep again. I watched the antifreeze slowly move up until it started spurting antifreeze all over the engine. I think I might have a air pocket in the engine. If this is right how do I get it out, if not I am open to any help I can get.

 

[CABBOTT]

Hmmm hope it's not a bad head or head gasket pressuring up the coolant system.

 

[mtnwhlr]

There is a trick I have used for years, when installing a thermostat drill a 1/6'' hole in the flange it will let any air escape. And are you sure you put it in the right direction.

 

[hdgapeach]

If a pocket of air is your problem, I've always made sure my replacement thermostats had a bleed hole in them before I install them. If the disc of the thermostat doesn't already have one provided in it, I use a wire size drill bit to add one tiny hole just to make sure air can escape past the disc.

Another possible method is to fill the radiator about 3/4 full, then take the top hose off of the radiator and pour coolant down the hose on top of the thermostat, reconnect the hose and top up the radiator.

Any way you do it, you at least need to get coolant on the thermostat spring to allow it to activate according to the coolant temp.

 

[Torxhead]

If you don't want to take it apart again to drill an air bleed hole, you could just drive it up and down steep hills to get the air to the top of the radiator. You could be in need of a coolant system flush also.

 

[elwood blues]

Cant you also remove the temperature sensor in the block while the engine is running, to help burb an air pocket?

Assuming the thermostat isn't in backwards

 

[rodman467]

when it comes to mechanics I love doing it but I have no problem if I am wrong. I placed the thermostat in with the spring towards the engine, is this correct?

 

[rodman467]

I took the thermostat out and put the housing back on the jeep and it ran good. I let it run for approx. 15 minutes and it did not get hot at all. I might be a complete idiot but when I put the thermostat back in it overheated within 15 minutes. I placed the thermostat with the spring towards the engine, is this correct or backwards.

 

[SlowPocono]

It seems like you have it right.
Try this.
It looks clear enough.

How to Replace Your Vehicle's Thermostat - For Dummies

 

[caveman]

It sounds like you might have a bad thermostat. Sometime even a new one will stick. Take the thermostat out and put it in a pot of water and heat it up on the stove. Observe when the thermostat opens and with a thermometer check the tempature. It should be stamped on the thermostat housing somewhere at what tempature it should open.

 

[IOPort51]

I still like the air pocket idea. I pull the temp sender on the top/ rear of the head to help get the air out. I think there is a chance to hold air in the heater as well.

 

[dsrt4]

I'm thinking air pocket as well. And I always drill a hole on these to help burp the air out. Chasing down a air pocket really does suck. Its real bad on rear engine cars with the rad in front.

 

[Turbogus]

In my FSM they list the procedure for burping the radiator and no drilling of the thermostat is nesessary. After all if it were they'dve thought of that at the factory, nicht var?
I was pulling what little there is left of my hair out when 'Black Betty' had her overheating issue every summer. Trying several tricks to get 'er within limits availed nothing. This went on for three summers until I pulled my head out and went with the Ford Contour fan setup on my 360, since completion last year she's behaving like a champ.

 

[Barry2]

I'm with caveman on this. .