Oil pressure relief valve
 

Hello,

I am looking for the oil pressure relief valve (CTL 645 A assembly) for my carrier.

Does anyone know where to find this part? According to part number, it was a special part for carriers but is there an equivalent part for commercial Ford trucks?

Best Regards,
Raphael

Where is that part located in the Carrier Oil system?

In trucks, there are 2 oil pressure valves, one is a component of the Oil Pump and another is located in the Oil Gallery in the block. They are still available for 50# and 80# systems.

It is outside the engine, above the clutch (see picture).

If we call it the oil cooler bypass valve, then others will know what it does.
It allows cold, thick oil to bypass the cooler, but only if it has a p.d. (electrical term= potential difference) of 3.5 pounds (approx)
Sorry I cannot direct you to one, Bauduin.

Oil cooler
 

Page 130, Illustration No. 26, FUC-03
Version SE-83-44, Reissued May, 1944.

Ctl 645a
 

Hi Raphael
I think I have what you are looking for. Give me your email address and I will send you photos of this part.
Best Regards
Adrian