odd overheat.

[Whiterabbit]

Been tracking down an overheat issue.
New water pump, old one's seals failed.
New thermostat.
Flushed and cleaned the cooling system a dozen times.

Last issue I thought might be causing the high rpm overheat was slightly loose belts. Nope.
Head torque good. Head gasket good.
What's this----
The rocker arm shaft was slightly rotated!
Low oil flow!! That was it!

Oh, vote for my M151A2 for MV of the month!
MUTTS RULE!!

 

[HILLBILLY 06]

Been tracking down an overheat issue.
New water pump, old one's seals failed.
New thermostat.
Flushed and cleaned the cooling system a dozen times.

Last issue I thought might be causing the high rpm overheat was slightly loose belts. Nope.
Head torque good. Head gasket good.
What's this----
The rocker arm shaft was slightly rotated!
Low oil flow!! That was it!

Oh, vote for my M151A2 for MV of the month!
MUTTS RULE!!

So having low oil flow and a slightly rotated rocker arm shaft can make it over heat?
Do you have low oil pressure in general, or just that one rocker that caused the issue?
Oh and I voted for your Mutt earlier, great looking all around...

 

[Flyingvan911]

You might remove the engine and pull out the freeze plugs. My friends engine was flushed a bunch too but when he pulled the freeze plugs he found a bunch of large junk in the coolant passages.

 

[Wheat1]

Might check timing also. Mine would overheat after about ten miles at highway speed. I put timing light on it and adjusted timing. That took care of problem.