12 valve screeching

[dieselmechanic101084]

12 valve has pressure in rad while cold and screeches for a split second and then goes away. Rad pressure climbs to 10 psi in 7 min. I think this is normal. Pulled thermostat and neck. Ran engine and no bubbles. What could be causing this?

 

[Nyoest]

Try running it with out the Belt. Might be an accessory causing the noise.

 

[tp0d]

Belt tensioner pulley

 

[dieselmechanic101084]

went and looked at it. Not a screech more like a blow gun noise. Found a/c compressor releif valve popping off.