7.3 empty hp resovior over night.

[OHNO60]

Hey any of you guys remember issues of 7.3 hp reservoirs draining down after overnight sit? Have a friend with the issue on a 2003 E-series.All of a sudden issue started, but can't remember the fix.

[gasgasman]

Usually the it's the base engine oil pump. Excessive clearances will cause the oil to bleed down.

[Bruce Amacker]

I don't agree with that. Due to the design of the HP reservoir since 95ish they have a standpipe where the oil is fed into the reservoir. This means gravity cannot cause the reservoir to drain back through the LPOP in most cases, but if there is a failed gasket under the reservoir this might not apply. In my experience, most reservoir drainback cases are a bad HPOP. If the check valve inside the HPOP leaks it allows the reservoir to bleed out. I have never seen the LPOP cause a reservoir drainback after 95.

 

A similar problem is if the reservoir is full in the morning, goes empty and stalls after 10-15 seconds running, that is commonly the LPOP.

 

Good Luck!

 

[blown99]

Before you condemn the hpop, inspect the ipr valve o-rings. If the o-ring is cut it can create a hard start condition. This usually creates a long crank when hot issue too.

I agree with Bruce on the lpop and reservoir stand pipe not being a cause of this complaint.

[OHNO60]

Thanks Guys! ended up being f'd up low pressure regulator in the oil cooler head. Ended up not allowing sufficient pressure build when engine was cold. Recent repair on the cooler at another facility caused problem.I appreciate the help.