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tripps 10-15-2025 07:45 PM

Valve cover condensation problem
 
Got some under covers motor runs 125 don't have bypass on manifold or bypass ,how about t I disconnect oil cooler to get oil temp up or do I need water temp up to get rid of condensation .I have a merc waterpump ran off crank pulley? Tia

Tartilla 10-16-2025 03:27 AM

You have 125f thermostat?

What is your oil remp?

Condensation is a factor, but you may be getting moisture in from the exhaust, or a weeping gasket. Evaporating some of it, and some condenses on the valve covers.

How is the oil on the dipstick?


tripps 10-16-2025 05:14 PM

Condensation
 
No the r mo Stat don't have the bypass set up I just put a restricted in thermohousing didn't get to try it yet oil on lipstick is mint has cmi ex not leaking

tripps 10-16-2025 05:18 PM

O
 
Don't know oil temp have cooler though I know I have t o make it hotter ,water and oil ,wen I take it out this s week send I'll try for oil temp readings

Griff 10-16-2025 09:06 PM

Is this after running the boat in the water for 30 mins + under load or ????

You need to determine the oil temp. Will probably need some type of kit or filter mount with a thermostat to build more oil temp.

SB 10-17-2025 04:24 AM


Originally Posted by tripps (Post 4936554)
Got some under covers motor runs 125 don't have bypass on manifold or bypass ,how about t I disconnect oil cooler to get oil temp up or do I need water temp up to get rid of condensation .I have a merc waterpump ran off crank pulley? Tia

New motor build ?
454 ? 502 or bigger ?

tripps 10-17-2025 08:20 PM

C
 
It's a fresh 502 w hp500 cam I'll try for temp I pan w temp gauge I don't r Un it for long time I know it's gotta run hotter

SB 10-17-2025 09:44 PM

Intake gasket leaking a tad ?

tripps 10-18-2025 03:52 AM

W
 
It's a fresh 5002 w Hp 500 cam cmi ex that don't leak is it cause of cold oil or cold water in block running merc sea pump ,no circulator,just. Inlet assembly

SB 10-18-2025 05:23 AM

Just throwing out what i’ve seen several times. Our lake freezes, therefore we’ve boated in some real cold water. Some have had no thermostats.

Also why i asked 454 or 502. Seen some 454 headbolts weep water as the blocks headbolt threads go thru deck into the coolant passage. The 502 blocks don’t. They are blind.

If you are convinced no leaks, you could try a pcv valve if your carburetor has a port for it.


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