cooling system issue

[badtbuick]

I'm trying to figure out if I need to change out the head gaskets, the main symptom I'm getting is when I shut the engine off I get bubbles in the overflow bottle, I am not getting any temp spikes no discoloration of the oil and when I did a chemical check the indicator fluid stayed blue, if its the gaskets so be it but I would like to rule out any external problem first before I dive in

 

[SHADOWII]

If the oil is not being contaminated, the radiator level is dropping, then the contents is passing thru the cylinders. Any steam coming thru the tail pipes, especially under hard excelleration?

 

[badtbuick]

Not really just some black smoke initially when I hit it otherwise its fine

 

[SHADOWII]

Is it possible the thermostat is failing and causing some boiling in the block? Are you actually losing any coolant?

 

[Flyin Brian]

Could it be your radiator cap is failing?

 

[badtbuick]

I am not loosing any coolant the level rises just a little bit when it I completely warmed up and goes back to the original level when cooled off the cap was bad so I changed it but the problem still persists

 

[machinegun]

Well I would look at the bubbles.

If you are not loosing coolant and you are not seeing contamination of oil and you have nothing in the exhaust I am leaning you do not have ahead gasket issue.

Get the car warm with the fans off and cooling system sealed and see if the top rad hose gets pressurized, shut the car off and see if the hose stays pressurized and how long it stays pressurized.

If it pressurizes and stays pressurized for 15 to 20 minutes or more than you have no coolant system leak.

You can follow the procedure below too.

First things first, get a coolant pressure testing kit.

with the car cold pressurize the system and see if you can find a pressure leak if any pressure loss.

If there is no pressure loss then get the vehicle warm and I mean very warm. Re perform the pressure test.

If you have no pressure loss then the air bubbles you are seeing is just trapped air in the system.

If you have pressure loss then trace down your location of pressure loss and resolve.

Hope this helps.

 

[belsie]

Another tip: while warming up turn heater on for full circulation and look for any wet areas in dash and carpet just in case. Heater core, valve etc...................

 

[John Larkin]

You can burp the system by taking the upper heater core line loose a little with the car running at full temp. Turn on the heater in the car so the valve opens and lets coolant circulate through the core. It will be hot (duh) so wear rubber gloves and eye protection. The air can escape at this high point and it might fix your problem. There will be a little cleanup but what's new?

My previous neighbor had very little heat in his Ranger for years until we did this and then it was like brand new. He was pissed.

 

[Pronto]

Go for a ride, stop and raise the hood. Reach in and shut off the engine. Listen closely for any "hiss". Mine stock engine did that and I had bubbles. Eventually I had foam in the radiator. Head gaskets were slightly blown into the valley.