Strange coolant issue on 5.3 motor

PittSpeed Automotive
1

I finally got the car all finished, but have been having a strange issue with cooling, almost like a over pressurizing of the system. I fill the radiator up, let the motor run with the cap off to get as much of the air out, and put the cap back on. After a few minutes of running water is pushing past the gaskets on the pump. If you turn the engine off, you can hear an air leak on the passenger head, by the sensor adaptor that will last for a minute or so.

Did, I did some more investigating and believe the issue is coming from that general area. I ran some more fluid through the radiator with the cap of, and it worked just fine. I picked up a new 18lbs rad cap and when the unit started to pull through, I turned the motor off and there is air pulling in from the passenger head that can be heard, but no visual leaks in the area, but coolant will push through the water pump seals. I’m going to get a new barb and see how that works.

Thanks,
Sean

2

was this combo ran before? if so have you done a leak down test or compression check? possibly hurt a head gasket and its pressurizing the system

3

x2

4

u sure you got all the air out? This motor has steam ports on the top of the heads on either side of the intake manifold and should have a small hose connected to them. Loosen the bolts on them and see if coolant comes out, if it does then all the air is out. If there isn’t any air in the system, then I would say there is a head gasket problem.

5

There are various things that can go wrong with cooling unit of a car, try using a 50/50 mix of antifreez and water if it’s empty or low, and close the cap.
Its best to visit a mechanic ensure you get it detected and repaired rather than trying various things on your own and causing something else in turn

6

this post was from 2 years ago, but thanks