Toasted the bearings. Anyone Know why?
07-11-2015, 12:37 PM
#11
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I used the whole oiling system from the 1998 7.4 mpi. The oil lines are pretty Small. I think 3/8. I pulled the block numbers. It's a gen v 1992 merc 370 hp. The previous motor had no issues. So not cross contamination from cooler..going forward. I think if I install the 30 psi bypass in the block and take out the other bypass in the center hole ,use the bigger cooler and lines ,and install oil temp gauge...I should be good. Does this sound right?
07-11-2015, 12:58 PM
#12
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Never re-use an oil cooler period. The example you gave of how the motor was running fine and then dropped rpm and oil pressure is a classic example of re-using an oil cooler.
Chris
Chris
07-11-2015, 03:30 PM
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07-12-2015, 09:45 AM
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07-12-2015, 10:13 AM
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Bearing materials can be stuck in old cooler if you re use, you can run no bypass but I use a 30 just in case, yes it could let some bad oil past but if you have oil temps you can catch it before it actually spins the bearing in a clog situation, cheaper to fix some scoring then actually spin it...
07-12-2015, 11:18 AM
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Did you reverse the oil lines when you installed it on the new engine? If you did, it will cause exactly what you are describing. I learned this the hard way in my younger life and the new engine also had 10 hours on it. If you reverse them, no oil will flow through the cooler. Toss the existing cooler, I even tossed the all the oil lines when I did this.
Good luck, but you need to find out what caused it, so you don't repeat it.
Good luck, but you need to find out what caused it, so you don't repeat it.
07-12-2015, 11:31 AM
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Did you reverse the oil lines when you installed it on the new engine? If you did, it will cause exactly what you are describing. I learned this the hard way in my younger life and the new engine also had 10 hours on it. If you reverse them, no oil will flow through the cooler. Toss the existing cooler, I even tossed the all the oil lines when I did this.
Good luck, but you need to find out what caused it, so you don't repeat it.
Good luck, but you need to find out what caused it, so you don't repeat it.
07-12-2015, 08:16 PM
#20
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I've got a similar set up with a 502/500hp using the standard 454 Mag MPI stuff, and want to switch it out without pulling the motor if possible. There's a fair amount of room to reach under the sandwich adaptor so it should be possible to spin the OEM Merc unit off and replace it, right? The bypass valve was replaced but I'm not so sure that the one under the nipple was removed, so I'll try to reach under there and get it (Hex wrench, right?)
From what I can tell the billit relocator kits use 1/2" barbed lines with pipe threads? It also looks like the merc cooler uses flared fittings so a new larger cooler will be in the plan.
I'm trying to gather as many parts as possible to minimize downtime and hair pulling, so any tips, tricks, and warnings are appreciated.
From what I can tell the billit relocator kits use 1/2" barbed lines with pipe threads? It also looks like the merc cooler uses flared fittings so a new larger cooler will be in the plan.
I'm trying to gather as many parts as possible to minimize downtime and hair pulling, so any tips, tricks, and warnings are appreciated.
