oil temps.
 

Ok 10 qt pans 300 degree temps , huge Hardin coolers ,5/8 oillines ,senders in pan,.... Boat definately runs higher than stock . Was a 60 mph boat now a 80 mph formula . Is the out drive suckin air and airrating the cooling water ?Should I plug a couple of holes in the drive .Water temp is a consistent 115 or 125 degrees .No bearing problems exist . What do you think ?

Re: oil temps.
 

Gen 5 or 6? Did you plug the bypass in the filter pad?

Re: oil temps.
 

Gen 6 and we did not plug the bypass

Re: oil temps.
 

Did you use the 30lb. bypass? Personally,I prefer to plug it to make sure all oil goes through the oil filter and oil cooler.

Re: oil temps.
 

not sure what bypass valve is installed but could enough oil slip by to raise the temps that much . What do you think about the out drive hole theory .

Re: oil temps.
 

now the bypass is actually in the block correct ?

Re: oil temps.
 

If your engines run that cool, it would seem that you're getting enough water. Make sure that the oil in the cooler flows in the opposite direction from the water. But that would only make a small difference, 10-20 degrees. The bypass is a very important thing. Alot of people have cooked thier engines from having the wrong one. There are a lot of threads here about it. Yes it's in the block, in the filter pad.. Hard to get to when the engine is in the boat. Is this a super charged engine? If so, even a 3 x 18 cooler might be too small. What size is yours? Any detonation raises temps fast. Running lean will also.

Re: oil temps.
 

twin 540s. Im not running lean . Shoul I try to block the bypass .At 3500 rpms I run about 250 degrees. At 5000 she rises fast 575 hp with 630 torque .Id be happy with a 30 degree drop in temp .

Re: oil temps.
 

My motors were pulled yesterday .

Re: oil temps.
 

one more thing 1050 dominators , jetted 90 squared. no blowers

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I have Dominators 92 jets and it's not lean. 3 x 18 should be enough cooler. Check this old thread about bypass's.http://www.offshoreonly.com/forums/s...ing+oil+bypass It's good even has pictures.

Re: oil temps.
 

how do I determine if I have a 30 psi or a 11 psi bypass valve. How can I plug it , If thats what I decide to do .
We checked the valve today it felt like it was sticking .

Re: oil temps.
 

My engine builder and I had this exact conversation just last week as I was curious what I had in my engine (i.e. bypass).
He told me he never uses a bypass as he likes all of the oil to go to the filter.
He also said we should be cutting the oil filters open, during oil changes, and inspecting the media for fragments.
In fact, one of our members was having oil pressure issues after a hard run. Pressure was very low at idle. He cut the filter open as recommended and discovered undesireable fragmentation. Motor came out and was disassembled to find a main bearing that was obviously the source of contamination in the oil filter. This filter inspection saved the motor components from a catostrophic failure.
Also, Oil Filter inspection is mandatory on all aircraft maintenance for this very reason.

Sorry to get off topic.

Re: oil temps.
 

Makes no difference if it's a auto block or a marine block, they're all the same. All gen 5 and 6 have this oiling set up. Maybe all Merc engines come with the proper bypass, but if you are rebuilding, you throw the bypass away before hot tanking the block. The part number is in that other post I linked to. I agree it's better to plug it.

Re: oil temps.
 

How do I plug it ?

Re: oil temps.
 

My engine guy did it. I'll ask him on Monday.

Re: oil temps.
 

I pressed a soft plug into the opening.. worked fine for several years..