I just installed an autometer water temp guage. And was shocked to see the temp rise to 240f after 10 min of driving.

While I was searching I came across a post that said aftermarket ast should have a restrictor in one of the nipples so that the coolant goes to the radiator instead of the ast.

I have a cheesy ast that is in the shape of a rotor that was on the car when I bought it and think that this may be one of my problems.

I have heard coolant boiling or bubbling in the ast.

How do I know if I have this restrictor or is it even such a thing.

 

Best way to find out is to cut it open.

Second best is to run the car from a cold start and feel the temperature of the of the top of the radiator versus the temperature of the AST. If the top of the radiator is cold and the AST is hot, most likely there is no restrictor.

Cut open the OEM AST, you'll see a restrictor built into it.

 

If this is the case can I add a restrictor? or should I get another ast?

 

Cut it open? Well, that would basically destroy the AST and render it worthless, regardless if it did have a restrictor or not.

What I suggest doing is the following:
1. The easiest way would be a visual inspection. Open up the cap and shine a bright light through the bottom of the nipple or from the top.

2. If that does not work and you happen to have a bunch of thin/long bolts lying around, slowly slide it in and see if you find a restriction of any kind. Having a stock AST might help you compare the ID.

Regardless of the design of the AST, 240F is ~115.55C, which is very hot especially after just 10 minutes of driving. This is a pressing issue, and prolonged exposure to high temps may/will result in coolant o-ring failure. It doesn't take much for our coolant o-rings to fail or begin to fail.

Many members on this board run aftermarket ASTs without that restrictor, and do not see this high of temperatures. There is something else wrong with your coolant system. It may be that the fans are not turning on, the pump is going bad, the coolant caps may be blown/not holding pressure, the thermostat is stuck closed, etc.

Good luck.

 

Best to not use an AST as they are worthless like turbo timers.

 

You are correct gramps. I found out that I have only one fan. How do I know if the air pump is going bad?

 

He means the water pump.

You only have one fan, or only have one working fan?

Does your stock temp gauge not read towards the top when your aftermarket gauge reads 240?