Rage

Russ,

Thanks for all the thought you have put into providing direction to solving my problem....especially for a competitor's product no less.. Admirable.

The Hardin Marine unit was purchased new from a boat dealer who apparently had it sitting on his shelf forever and posted it on Ebay. The unit is all brass and copper construction except I guess is silver solder holding it together. It had a lot of green copper oxidation on the exterior which I cleaned and painted black. I do not know where aluminum oxide could come from since no aluminum components appear to be present.
I could see the thermostat spring and guts inside the housing and it appeared clean and uncorroded subject to confirmation. I thermocoupled the oil bypass tube and it did seem to maintain the ~190F setting when the engine oil temperature was much hotter than that.

My next step will be to try an extended WOT run with the oil cooler now replumbed to be counter flow instead of parrallel flow. Any good thoughts towards reducing max oil temperature during extended WOT running will also be tried.

BenPerfected

My thought is to remove the thermstat and do a WOT extended run. The thermostat is really a flow restrictor to build and then control the oil temp at a set level. This way you will know if your cooler is capabile of controlling the temp that your combination is creating. If you still build too much oil temp, you will now know the engine and or cooling system is creating too much heat for this size cooler. At least you will eliminate a varible and you can be more focused on the potential causes. This is also a low cost test

Rage

When I upgraded to the current ~600hp level I still had the stock 425hp oil cooler and no oil temperature gage. During WOT runs to document AFR for ECU recal I noticed oil pressure really dropping. An oil temp gage and the Hardin oil cooler was then added but I retained the stock oil lines & fittings the latter being a bad idea. This was my first look at the actual oil temperature numbers coming out of the engine at WOT. It got hot quick but the oil pressure did not drop near as much as before so it must have been REALLY HOT back then probably 300F+. The following winter I replaced all the stock oil lines and fittings with AN-10. Three of the stock invereted flare oil line fittings were 3/8" ID. The max oil pressure increased significantly with those restrictions removed and it did seem to take a little longer at WOT before the oil temperature got to my personal max limit of 270F out of the engine to shut it down.

My Bravo drive has the low water pick up as stock along with the side pick ups. I plugged the side pickup holes that run above the water at WOT full trim to minimize water pressure loss or air induction or at least that was my hope. It was suggested that drilling the low water pick up inlet holes larger would increase flow which I did as well. Since the sea water pressure readout that the PCM555 ECU presents has a max scale limit of 43 psi wghich I was already running at I do not know how much this improved sea water flow/pressure.

To make sure that I was getting adequate sea water flow through the HE, and not just a high pressure do to some restriction, I temporarily added a 5/8" sea water dump line just down stream of the HE. The max sea water pressure at WOT dropped from 43 psi fdull scale to about 38 psi so the flow through the HE had to have increased but the WOT run time before oil heat up did not change noticably. So the water flow rate was probably fine before adding the dump line.

Rage

Steve, Yes the oil pan is totally stock and running 10 qts per 496HO specs. I did try running a quart low at WOT because Innovation said that that was good for reducing max saturated engine oil temperature during the race and adding a few hp at least on the dyno. I really did not notice any improvement in the oil heat up problem running a quart low. What size oil coolers did you run if you recall? Of course your hp would have been some what less I assume. Do you think that was the windage issue fix you mention? The parts list I got from Innovation to convert my engine to an HP3 did not include any crank case parts except for the HV oil pump. If I am being dense and missing out on something else here please let me know.

Rage

I run on a pristine highland reservoir so no normal need for a sea strainer. Mr Cool what do you think about a sea strainer reducing areation of sea water to the HE?

Rage

BenPerfected I like low cost tests and its a good thought.

Unfortunatelly this oil cooler thermostat does not restrict oil flow through the cooling section to raise oil temperature to the set temp but instead this thermostat stays open allowing some (not all) of the oil to bypass the cooling section until the set temperature is reached and then it closes off the bypass so 100% of the oil now has to flow through the cooling section.

BenPerfected

I did not know about this cooler design. Besides trying a larger cooler (would you be able to borrow one?) maybe use an infrared temp gun and see what engine parts or accessories are excessively hot after you make a run. These guns should be pretty easy to borrow.
We once had a engine temp issue (Stb 20 degrees hotter) and it turned out to a blocked internal water passage in a Mercury thermostat housing....the really strange looking one in the 80's. You could not see it and the we finally isolated it by Stb/Port parts swapping. As you might imagine, we tried lots of things before we finally swapped these parts...took two years!...hope you can beat that!

Rage

In my effort to ID my oil temp problem I have acquired a lot of stuff including an infared temp gun and two quick tip thermo couple temperature devices. Just tell me what to check and I will be on it.

BenPerfected

I would aim the temp gun at everything that has water in it. Intake, exhaust, heads, various points on the block, etc. Assuming you have twins, measuring back and forth between engines might show a variance. If you run a single, try comparing side to side.
We actually had a second high temp issue back when we had Gil manifolds. I big flap/piece of powder coating delaminated inside the manifold and was restricting the flow at the fitting where the 1" hose jumped to the tail pipe. As it didn't totally stop the flow, it was difficult to detect. This also took a long time to figure out. Both these restrictions caused the water temp to rise. We didn't have water pressure gauges at the time.
Do you measure your water pressure?

smiklos@sunprint

iTrader: (1)

I am sticking with windage.
Steve