GM mechanics ????

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Feb 21, 2007 | 08:22 AM

jetdoc

Thread Starter

Cargo Master

Joined: Jan 2005

Posts: 2,902

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From: Pasadena, Maryland

GM mechanics ????

I work for a local marina part time. Yesterday I was asked to disassemble a 454 engine. This engine had been installed two years previously and was supposed to be a new GM engine. The engine had disintergrated one piston and had damage to the rest. I pulled what appeared to be the best looking piston to find a crack in the dome and skirt. The rods had been previously numbered, however they were not in order and I found two number 1 rods! My question is, The pistons were installed with the dimple in the dome facing aft. Would that cause the damage I found. Also, I found GM markings on everything except the bearings and pistons. Is that right? I remember when I bought bearings from Ford before they were marked with the familiar oval. Thanks in advance!

Feb 21, 2007 | 08:24 AM

jetdoc

Thread Starter

Cargo Master

Joined: Jan 2005

Posts: 2,902

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From: Pasadena, Maryland

This engine is a port side engine so it is counter rotating. This was the second engine installed from this supplier. The next one is coming from someone else!

Feb 22, 2007 | 07:24 AM

GlennFordx4

Fleet Mechanic

Joined: Jan 2005

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From: cape may county NJ

I know a guy at my marina that went thru four 454 merc cruser engines last season all due to bad oil pumps, want to talk about a unhappy camper the mechanic spent more time on his boat then he did.

Feb 23, 2007 | 05:03 AM

jetdoc

Thread Starter

Cargo Master

Joined: Jan 2005

Posts: 2,902

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From: Pasadena, Maryland

I wish the problem was like that, the bearings were in good shape though. Four times! Look on the bright side, at least you'll have the routine down for the vessel!

Feb 23, 2007 | 10:36 PM

5_labsownus

FTE Chapter Leader

Joined: May 2002

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From: Fraziers Bottom, WV

The cracked piston skirts is due to repeated excessive RPM (over red-line)!

Will happen to any engine.

Feb 23, 2007 | 11:10 PM

Ford_Six

Hotshot

Joined: Oct 2002

Posts: 18,488

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From: The Big, Oregon

I learned from a boat I worked on that rod numbering on GM engines was a joke. They aren't marked from the factory, some rebuilders number them, but it's not really needed, aside from confirming that a cap and rod go together.