lake speed

yes the jetting is the same. it is not a rebuild this is a totally new motor. I started witht the same jets and was going to work from there. the plugs are nice and brown with no hint of detonation. if it was detonating to the point of heating the oil wouldnt you guys think there would be some splatter on the plugs? or at least the plugs look white? the oil temp will heat up to 140 while letting the boat idle for a bit through the no wake zone. as soon as I get the boat up on plane the oil temp gradually inreases and will continue to inrease until I slow down. when I slow down and go through an idle zone the oil temp doesnt really come down like it should. the temp will decrease but not like it did with my old motor. the only way to get the oil to cool down totally is to shut the motor off and let it sit for awhile. the is the exact same oil system that I had on my other motor and it worked great. If the bearing clearances were too tight wouldnt the oil cool down at idle? I can let the oil ccol with the motor off and after starting it again it will idle all day at 140-150 degrees of oil temp but as soon as you get up on plane it heats back up?

lake speed

I am going to a lighter weight oil and try reducing the oil level by a quart to see what happens. I know no one on here like fram filters but I am also going to try the hp4 filter instead of the mercury filter. At this point I guess its a process of elimination

Panther

how much water pressure are you running? Are you running a thermostat?

lake speed

no thermostat and I have about 2-3 psi at idle. should I try a thermostat to increase water psi and slow the flow down through the cooler?

lake speed

or at least a restrictor?

fastlane40

interesting.I'm having the same trouble with new 632's.Almost identical set up to you.Dart block,canton adapter,18x3 cooler,an12 lines,canton offshore pans,oil senders in the pan,crossovers and no thermostats at present due to water pressure issues.First lap and on it went to 260,slowed to 5000rpm and came down to 230.I too am wondering if the cooler is too small.I'm not sure about a restrictor.Definetly need a thermostat to get the motor temp up.

Panther

It depends, how much PSI are you running underway?

lake speed

well I just tried a 160 degree thermostat and all that did was raise the oil temp.

SpeedMaster

Your oil is NOT flowing through the cooler.
Could be the oil adaptor, ie the lines to the cooler and return,
Could be a plug not fitted in the oil gallery and allowing the oil to bypass the filter and cooler,
or ???? many other reasons, put an inline pressure gauge on the cooler line.

Your motor is behaving like it has no Cooler.

Steve

SpeedMaster

Sounds like you are racing.....First lap and on

A 632 is 4.6 x 4.75 stroke,
you are running a wet sump and a 'tiny' cooler, what do you expect?
The oil cannot return past the massive area of the rotating assembly.
You need a dry sump or external oil drains AND more cooler.

Steve