Hey Tom thanks for no guesses and please do not appologize. I should and do appoligize for asking so many questions. It is a notorious problem of mine.

My Smart Craft gage says water psi at the water pump outlet is 2-3 psi at idle and 43 psi max at some rpm before WOT up to WOT like a pressure relief valve is kicking in. Nobody seems to believe the 43 psi number. The Smart Craft gage reads the data from the ECU that reads the sensors. 'Mercury For Consumers' tech line said that the pressure head at the lower Bravo water pickup is 100 psi at 80 mph. No idea if this is true. Where/how did you tap into the water pressure at the heat exchanger? 10psi sounds real low but I have no basis for that opinion so it is worthless. Did you or the previous owner ever destroy a water pump impeller? Pieces of the rubber can go everywhere and plug up everything. I've had that pleasure.

With ported heads you should be making more than the 650 hp (& heat) published by Whipple for his kit with stock heads. Did the previous owner change the oil pump to a high volume unit?

Please post any numbers that you come up with in the future.

Good luck,

Bill

ttt

I have been through the cooling system looking for blockage everywhere. The only place I haven't been is in the transom assy. With the loss of water flow cooling the engine going to the inter cooler and the power this motor is making it just makes sense to have a transom water pick up. I don't mind a little speed loss with the added drag.(OMG did I just say that)
I don't know about the high vol oil pump but I watch the oil press constantly and have never felt it was low.

Oh, and I take the water press from a fitting I made right before the raw water goes through the heat exchanger.

Tom

So you have the intercooler hooked up to the engine's sea water pump feed. I know very little about Whippled 496 sea water plumbing recomendations but have heard often that supercharger intercoolers are set up with a dedicated transum water pickup. If you have not already talked to Dustin Whipple about this you might want to to get his input.

I was also considering a dedicated water pick up for my oil cooler until I was told of potential for water areation problems with these on stepped hulls like I have.

What oil pressure numbers do you see at WOT?

Would you happen to have a picture that you could post of this heat exchanger fitting installation?

Thanks,

Bill

Hey Bill,
I hooked up a water press gauge to where to raw water goes to the port side header. I put a "T" on the starboard side header feed and ran a water line over to the port header. This allows all the raw water to go through the heat exchanger. Its just something I came up with to try to cool things down.
If I remember correctly my oil press is 60 psi ish at WOT.

I don't think I can put up any pics any more, I let my membership expire.

Did your revised sea water plumbing improve the water temperature?

60 psi oil pressure at WOT, you are fine. I wish I had 60 psi at WOT. I am in the low 50's at 5800 rpm.

If you can still post your comments I think you can still post pictures. I think. But the clock is probably ticking.

Plane Silly,

While trying to post a picture of my Hering prop recently, I noticed that OSO had changed its format to add pictures to the threads. The icon is now above the text box, in the form of a picture box or a paperclip.

Chris

Just brainstorming. How sure are you that you have a 120F thermostat. The stock 496HO thermostat is a 160F and the coolant typically runs up to 180F during hard running. Second thought. If you are staying in the 60 psi oil pressure during hard WOT runs with a replacement crank and bearings (which always have bigger running clearances than the stock) I have real trouble imagining that your oil temps are at all high. If your oil temps are not high then 180F water temperatures should not even be a problem if in fact that 180F value is not erronoeus. Third thought since you are cooling the intercooler with the engine's sea water that is heating up the sea water in addition to the normal engine heat so coolant temperatures should be expected to be hotter. Did you check with Dustin Whipple regarding your issue and the fact that your engine sea water is being used to cool the intercooler?

Bill

10 mile long run today at 90+ MPH - WOT:

62 deg air temp
59 deg water temp

Coolant at 150 deg.
Oil temp at 180 deg.

Chris

My innercooler tee's off of the main water line, right after the raw water pump, goes thru the innercooler, and then dumps out the back of the boat.

After that tee,The main water line goes thru the fuel cooler, then thru the oil cooler, then thru the power steering cooler, then thru the heat exchanger, then thru the headers, and then dumps the raw water about a foot back from the collector flange. This is the way Dustin told me to do it.

He said that if I was having pressure or heat problems with the engine, that I should use a thru hull pickup with a strainer for just the innercooler.

Currently, all the water for my boat is coming from my IMCO drive.

Chris