Thermostatic oil cooler?
 

HELP!!!Was getting ready to purchase a t-stat oil cooler, but notice the Merc. oil filter adapter shows one internally? My oil temps are too low(<170 cruising, 200 deg. after long WOT pass) and I'm getting excessive condensation in motor. It is a '97 HP500 with 3.3 Whipple, no cooling system t-stat, just 5/8 restrictor disc. and crossover. Rear of intake tapped to bleed off water. Oil pressure 60 lbs. max.,35 at idle. Head gaskets good, and no mechanical issues with motor.
I boat in the NW, usually cold water temps and 70-80 deg. ambient.
Engine also runs very cold, usually will barely register on gauge, and yes it works.
Should I bring cooling system temps up, thereby raising oil temp? I could plumb the stock check balls and tee back in.
Or should I just address oil temp? Shouldn't the Merc. oil t-stat be working? I have disassembled the oil filter adapter and I'm going to test the t-stat plunger.......

Re: Thermostatic oil cooler?
 

I would try some thermostats first. 142 and 160. It definitely helped me during the late season runs. I run a crossover with bypass, and 160 T-stat has three holes in it. Holes are .155"
Do you have milk under the valve covers?

Re: Thermostatic oil cooler?
 

Yes, pretty milkshaked. I have a bung on top of crossover, I could put the Merc. tee w/check balls on, and a thermostat in the housing.

Re: Thermostatic oil cooler?
 

Crossovers can be a pain. I have been through the ups and downs.
Dean Nickerson clued me in on my current setup and it is successful. My crossover is a Stainless Marine. I usually run a 142 T-stat with (3) .188" holes, for the warmer months. I do use a Mercury Racing Oil T-Stat filter mount, also.

Re: Thermostatic oil cooler?
 

RLW, If you have a bypass what is the purpose of the 3 holes in the thermostat?

Re: Thermostatic oil cooler?
 

I would say to keep steam pockets from forming. My motor tilts back a ways, I will probably do a 3/16" hole at top of t-stat.

Re: Thermostatic oil cooler?
 

Yes, the (3) holes help keep some flow of water through the block so steam pockets do not form. That is what I have been told.
The bypass maintains a supply of water flowing to the exhaust manifolds.

HP350C,
I do not know what one 3/16" hole is going to do for you. Try it and let us know how you make out.

Re: Thermostatic oil cooler?
 

That makes sense.

Re: Thermostatic oil cooler?
 

Took apart my oil filter adapter and tested oil t-stat, no worky at all at 210 deg. Will replace that and report back. I don't think it has worked since I bought the boat, and I did not know there was a t-stat in there.

Re: Thermostatic oil cooler?
 

i thought the holes in the t stat were to keep some water flowing thru the exhaust to keep it from getting too hot while the engine has the t stat closed.

Re: Thermostatic oil cooler?
 

If there was a working oil thermostat, would a water thermostat be necessary? I also have a crossover with no cooling thermostat and I can't get the oil warm enough to "cook off the condensation". I was thinking of installing oil thermostats (210 degree) to help. If a cooling t-stat works, it would be easier to install than an oil t-stat.

Thanks

Re: Thermostatic oil cooler?
 

I have had my ups and downs with crossover systems. I presently use one with excellent results. I also use a Mercury Racing Oil T-Stat filter mount to control oil temps and a Mercury Racing Water Pressure relief valve.
I run a 142* Water T-Stat with (3) 3/16" holes drilled in it. Crossover also has a bypass with a 3/8" orifice installed in the 5/8" hose that runs to the T-Stat housing. I have had no problems with temps or pressures until this year, late in the season. Lake water temps were very cold. It was noticeable in the hydraulic steering as it was stiff. I did notice that my oil temps were not as warm as in the summer months. I changed out the 142 T-stat to a 160 T-Stat and all was fine. The warmer motor helped in bringing the oil temps up. All of the water T-Stats I use have three holes drilled in them.
There are many variables to consider when designing a water or oil cooling system.
I agree, it is not a bolt on system. It is all trial and error.

Here is a pic of my setup when I was running Stainless Marine exhaust. I presently am using the Keith Eickert headers which are susceptible to meltdown without enough of a supply of cooling water. You can see the hoses coming off of the T-Stat housing. Three holes in a T-Stat is not enough flow to cool your exhaust system regardless of what exhaust system you are running.

Re: Thermostatic oil cooler?
 

Yes I run a Merc. pressure relief valve too. I will probably go with a 120 deg. t-stat being s/c. As soon as I get the engine/oil temps. where I want them, I am taking the temp. gauge out and putting a water pressure gauge in. Reason being, there is already an overheat beeper, and if you have water pressure at the block there should be no issues. I don't have a strainer yet, and the low water pickup is great at picking up pebbles that plug the oil cooler tubes. Monitoring water pressure will keep me on top of developing problems.