Coolant fluid boiling on

[tommy_boyz_18]

Trans Am? Coolant fluid boiling on Pontiac Trans Am
Hello. A friend of mine has an '88 Trans Am and would like some help on this subject. Here's his question.


"Ey guys,

really need some help on this.

After driving a while....I find that my coolant fluid is boiling in the coolant reservoir. And I really have no clue any more what the problem can be.

There is a new thermastat in the car (witch works) Kicks in around 220...and then the temperture drops back.

Weird thing is....while the coolant fluid is boiling...the engine temp stays pretty low?

Could it be the waterpump?

HELP!!!"

 

[karl g]

Possably...
I hope for you its not a hed gasket!!
Is there any white smoke commin out of the exaust.Plus What degree thermostat did ya put in>>/ They are usauly 180 dg or 190 dg 220 is pretty hot

 

[Christian]

Nope, is the gauge right ???

You mentioned the fan is working, so when the coolant is boiling look at the overflow jug, if it is air coming into the jug then most likely your are looking at a blown head gasket

 

[joejoe]

no this wouldent be the waterpump unless it was leaking antifreeze from the pump ur problem is you probley just got done putting on the theromstat iam only guessing u probley removed the antifreeze whell when u put new it keep the cap off on the radiatior for bout 10 minutes itell its warm and reading normal u have to mush air in the motor ive had this problem all to many time if this dont help try replacing the cap on the radiator GOOD LUCK!!

______________________________

 

[wde3477]

Welcome to the site!

Hard to tell - at 220degF, getting pretty close to the boiling point of 50/50 mix antifreeze if it's not under pressure. Need to ensure that the radiator cap is holding the appropriate pressure - at 15psi, the boiling point is raised up into the 260+ degF range.

Your comment about the boiling without the engine 'seeming' to be hot has me wondering, if like a previous post-er suggested, that you may have a head gasket problem - where the fluid isn't really boiling, just seeing the escaping air that is being pushed into the coolant system.

Since the engine does cool back down after peaking at 220 - would place the water pump further down on the list of possibilities.