89Mach1

So we just bought a 93 32' Fountain Fever a few weeks ago and I have a few questions on oil temps.

It's got carbed HP500's, and gauges read as followed at 3200 rpm.

Port motor-

Water Pressure- 21psi
Oil Pressure- 70
Oil Temp- 195
Water Temp- 125

Starboard Motor-

Water Pressure- 21
Oil Pressure- 70
Oil Temp- 220
Water Temp- 120

After a WOT run for about a mile or two port motor oil temp raises to maybe 210 and starboard motor oil temp up to 240, both water temps up to 140ish.

Starboard motor has a little bit of mayo crap under oil fill cap and port motor has at least double maybe triple the amount, and actually just came through the breather tube onto flame arrestor yesterday after a quick blast to WOT. Oil levels are right where they should be with no gain or loss over the past 3 weeks, about 12 hrs, and oil looks fine on dipstick. I'm assuming this is a condensation issue, and obviously port motor is running cooler oil temps so that would explain why it's got more crud than the starboard motor. So my question is, how do I get oil temps up on the port motor to burn off any condensation? And once I get temps up, should I try to clean out under the valve covers or will it burn off? Also, I don't believe there is a pcv valve, just 2 stainless hoses coming from valve covers to flame arrestor.

Thanks!

Jay

Black Baja

iTrader: (2)

Just run it wide open all the time.

Drew555

It should steam out. But why is it in there. I would check the pipes for leaking issues. You can change you t-stats to a higher temp. You probably have 140s in there. Or like the others say just pin it lol

89Mach1

Maybe try 160 t-stat then? It's got IMCO exhaust I believe, have there been issues in the past with them? Anyone have any idea why one motor is running cooler oil temps than the other? Anything else I can check? There's got to be a real solution other than pin it all the time.

Griff

I would install new 140* T stats first. That is stock on HP500's. I'm thinking somebody maybe swapped them out for 120's.
At idle it should get to 135-140 on the water temp gauge. After a hard run it should get to 150.
Make sure to use a Merc gasket or gauge wont ground and read at all.
Carbed HP500's also had issues with reversion at idle due to the cam used in them. Merc changed the riser design on the Gil exhaust to help reduce reversion.
If you have Imco exhaust, it does not have risers with as much angle as the newer design Gils.

89Mach1

Thanks, the 120 actually seems to make sense at the temps it runs at cruise. I'll have to pick up some 140's this week and swap them out. So I'm not sure exactly what you mean about the IMCO exhaust, reversion wise, do you think they are fine or not? They are the power flow with silent choice, but I don't use the silent choice as the previous owner has the air actuators zip tied open.

Griff

The Imco Powerflows with silent choice could easily be causing some reversion at idle. The cam overlap causes water to be sucked back up the risers at low rpms.
It makes no difference if the exhaust is open or closed. The risers still mix water at the same place and not close enough to the transom.

Bumping the idle speed up to about 850-900rpms will help reduce reversion. Its not great on Bravo's but they should be fine.