f250 temp alarm

[mullet76]

Pulled the smaller of the two thermostats last night and it looked pretty dirty. Covered in a silky mud film with a little corrosion around it. Scraped a little corrosion out of the housing but other than that looked pretty good further in the engine block from what I could see with a light. Going to replace the smaller thermostat and the pressure relief valve today and hope this solves my problem.

[rodbolt17]

whuuut???
there are not but two T-stats in that engine, both are the same size and part number.

on some of the later F250 stuff the original 69j pressure control valve may superceed to the 6AW.

I would find a dealership, or local tech, with a good borescope and have the ex stack inspected.
however pumps,t-stats and pressure valves are actually part of routine maint.

[mullet76]

whuuut???
there are not but two T-stats in that engine, both are the same size and part number.

on some of the later F250 stuff the original 69j pressure control valve may superceed to the 6AW.

I would find a dealership, or local tech, with a good borescope and have the ex stack inspected.
however pumps,t-stats and pressure valves are actually part of routine maint.

Yep, their the same size, I thought one looked larger than the other. After installing everything, no luck, still get the alarm after running in the tub for about 15 minutes. When I installed the new impeller the housing didn't look to be in perfect shape so I'm hoping a gasket is maybe pinched or something. I also get more bubbles than I think I should see coming from the top of the foot, but it is just under water so maybe it's normal.

[boscoe99]

If the motor is over heating at idle, with the boat in the water, but it runs fine at power, check the damn exhaust system.

[mullet76]

Problem fixed. Replaced water pump housing, old one didn't seal good. Ran for over an hour in the tub with no alarm shut it down for about 30 minutes than did it again.