Raylar

Verify your pan capacity with your Merc model engine but I believe that would be a 6 quart pan. If it is 9 quats would be to much oil but if the dipstick is correct and in correctly that should be pretty easy to confirm.

Best Regards,
Ray @ Raylar

BillK

hd,
Before running the engine again, I really think it would be a good idea to pull the oil filter and cut it open to examine it for bearing material. If the oil was circulating backwards, you will need to look in the center of the filter, not the outer layer like normal. If the temp really got up to 310 something is wrong and it might not only be the plumbing direction.

Just my opinion,

Bill Koustenis
Advanced Automotive Machine
Waldorf Md

Carbon Footprint

iTrader: (4)

Plumbing was correct, with the exception of going through the filter backwards. Out of engine outside port into filter center port out of filter outside port into top of oil cooler(downriver) out of cooler (raw water side) and back to engine center port.
Is just that and the oil being 2 qts high enough to cause a temp issue?

FIXX

iTrader: (2)

after the rebuild,the engine's oil pan will hold 7-8 qts and filter ,lines and cooler should hold 1-1.5 qts.

Griff

My 502mpi takes 8 qts with an oil and filter change. There is probably another half quart in the cooler and lines that never comes out.
I doubt being overfull is the issue.

Carbon Footprint

iTrader: (4)

What about the lines at the oil filter being reversed?

Mbam

If the oil level get's high enough so the crank is hitting the oil the temp goes through the roof - On the dyno we used to see about a 15 HP loss for each extra quart. That lost HP = heat. I always check to see where the full mark on the stick is in relation to the windage tray. There is a windage tray, yes?

Where is the temp sender? Is it in the filter adapter? With the routing you have it would be measuring the temp before the cooler.

Me, I always like the sender in the pan. If not there then on the outlet of the cooler, or in the oil galley in the block.

And yes - as Bill says take a look at the filter, that can either be depressing or reassuring.

Just an afterthought, what kind/weight of oil?

articfriends

iTrader: (1)

If your oil flow thru the filter was restricted to hardly anything (which is what it probably did being plumbed wrong) the factory block bypass valve would most likely open IF you still have one. At this point your motor would be getting un-filtered oil that has also bypassed the cooler. If you tried to drive it like this it WOULD get pretty hot. I would be more worried about getting the plumbing correct and finding out IF motor got hurt than possibly having too much oil. As soon as you run it plumbed correctly you should watch oil pressure closely and be cutting filter open and looking for debris/metal after short time. If you find alot, pull motor out before you destroy alot of parts, Smitty

Griff

As articfriends said, that would definately cause a problem and the higher temps.

Carbon Footprint

iTrader: (4)

update:

so tuesday before leaving for Havasu, swapped lines at oil filter (that was the only thing that was plumbed wrong) and checked filter for debris. The filter was clean so I installed a new one. I also pulled my IAC and found it to be rusty and stuck in the closed position. I went out for a quick lake test and immediately noted a HUGE improvement. Oil pressure solid at 60-70 and oil temps never got above 180. Once I ran it a little harder oil got to 200 or so and never any hotter than that.
Thanks to everyone for their engine saving input!!
The idle is still inconsistent though, after running for about 7 hours at havasu, it still wants to die when brought back to idle slowly, and just poking around in the canal, it felt like it could die at any minute, and did more than once. If you bring the idle up to 1000 is very pulsating but eventually evens out and won't die at that rpm level. I changed the map sensor on one day using a friends that was working fine on his boat, but still no change. I looked for manifold leaks with spray test but none are apparent.
Any ideas?
1997 GenVI 502 mpi with vst and mefi1
Only issue is at idle, the boat jumps out of the hole with no hesitation, and pulls very hard all the way to 5000 with no issues at all. The boat ran 67 gps with a 23p hydro Q4