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Advice needed on 1988 OMC 50L replacement

H

hometowndog

New member
"I have a very clean 1988 Bayl

"I have a very clean 1988 Bayliner 19.5 foot Bowrider with a OMC 5.0L and OMC Cobra stern drive. The motor has a cracked block, and maybe possible damage to the exhaust manifolds due to improper winterizing. Should I get a long-block replacement and move my existing parts over or should I upgrade to a 5.7L or 7.5L. If I upgrade, will the outdrive need to be replaced?
I am a good mechanic, but this is my first experience with marine applications. It appears from internet browsing that the 5.0L is normally replaced with the 5.7L. Will most of my parts transfer to this engine?
Thanks."
 
Is it a Chevy 5.0 or a Ford?

Is it a Chevy 5.0 or a Ford? Very expensive to switch everything over--even more so with a 7.5 liter.

A long block is usually hte best way to go.

Jeff
 
"It is a Chevy. Not sure I und

"It is a Chevy. Not sure I understand your response. Are you saying it is expensive to switch everything over to a 5.7L because the parts are not interchangeable or because of labor? What about the outdrive, is my current outdrive compatible with a 5.7 or 7.5 engine?
Thanks."
 
"A "5.7" is a Chevy. A

"A "5.7" is a Chevy. A 5.8 liter is a Ford 351. Most things will interchange between a Ford 5.0 and 5.8, but it's a different engine in many ways. The "7.5" (460) is an entirely different motor.

Any Ford experts out there to offer him some advice?

Jeff"
 
"Thanks Jeff. Here is what Mar

"Thanks Jeff. Here is what Marine Engines.com & Michigan Motorz says about their NEW 2006 GM 5.7L base marine engine, standard rotation: "Direct replacement for 1987 thru 1995 305 ci (5.0L), 350 ci (5.7L) Mercruiser, Volvo Penta, OMC, Indmar, etc..." So does this mean the parts needed to complete this base engine, such as the intake manifold, can be taken from my 1988 OMC (Chevy)305ci ? I would prefer to use the 5.7L as a replacement if possible.
Thanks."
 
"Most everything will switch o

"Most everything will switch over. The only thing is if it is carburated or an F.I. unit. The carb and manifold will bolt right up, although you might want to go with a slightly larger carb. On an F.I. motor, the computer might need a different chip for the best operation. The gearing should be the same in the lower unit for both engines. I've done this swap in cars numerous times with good results. I can't see there being any problems. Go for it!"
 
I was wandering what happen wa

I was wandering what happen was it not winterized at all or did someone do something wrong?
 
"Obviuosly, someone did someth

"Obviuosly, someone did something plenty wrong! Yours makes the 28th engine wrecked by poor winterizing this year--I've kept count.

Jeff"
 
so is the bucket of AF and muf

so is the bucket of AF and muffs OK as long as I get the engine hot to open up the thermostat ? I am abit worried I was told it would have to stay in the 20s for over 24 hours to cause damage..
 
"This was my daughter and son-

"This was my daughter and son-in-law's boat. They took it to an authorized marine dealer to have it winterized, then they stored it for two years. When they took it out of storage my son-in-law hooked up a water supply hose to check the engine and get it running. The motor started right up, but when he went back to look it over he found water coming out the side of the block above the freeze plugs. He was not real specific on where the leak was on the engine. He then shut it down right away. Do you suppose there was a water valve left open from the winterizing process that he did not close, and it was leaking water and made it appear it was coming from the block? Just a thought."
 
Pull the intake manifold and y

Pull the intake manifold and you'll see a nice long crack in the block just below it. Yikes!

That makes 29 wrecked engines this year alone due to poor winterization.

Jeff
 
"Dan...on that engine there sh

"Dan...on that engine there should be 2 petcocks down low, one on each side of the block that they use to drain the block, if it's leaking above the core plugs then it doesn't sound good. Question though, if it was done professionally why don't you go back as they should be responsible to make it good?"
 
Swap it out with another 5.0L.

Swap it out with another 5.0L. In some cases the fly wheel will need to be replaced. I tried doing that in my 89 bayliner ( go from a 5 liter to a 5.8 and found out that I needed a new flywheel for the swap. for the 20 Hp gain its not worth it. youre better off swapping the manifold and adding a 650CFM 4Brl carb.
Rob
 
Hey Guys I have an 89 Arrow b

Hey Guys I have an 89 Arrow boat with a Ford 4cyl engine. I wanted to test engine(on tlr)and when i hooked up waterhose to lower unit water began to come out somewhere at rear of engine (seems to be where engine and outter unit connects) What could be the prob? (just bought boat so this is all new to me)
 
"B Alan...you should really st

"B Alan...you should really start a new thread for a new question/problem. To answer your question though nothing is wrong, (assuming this on the outside of the boat and not inside?) it's perfectly normal for water to exit up there, a lot of the OMC's actually have exhaust bellows with slits cut in them to help reduce back pressure while idling"
 
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