Marine Flywheel compared to an auto flywheel

Ed Harris

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Why is the marine flywheel so much heavier than a flywheel used in automobiles? I have a 1996 5.7L Mercruiser and it is in need of a new flywheel. Current flywheel has some missing teeth and I really dont want to get stranded at the sandbar and require a tow home.
 

kenny nunez

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The ring gear is replaceable. NAPA stocks the ring gear, just count the teeth. It is easy to knock the damaged one off with a brass drift and a suitable hammer. You heat the replacement in your stove and it will drop on and shrink itself out tighten up.
 

Scott Danforth

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Why is the marine flywheel so much heavier than a flywheel used in automobiles? I have a 1996 5.7L Mercruiser and it is in need of a new flywheel. Current flywheel has some missing teeth and I really dont want to get stranded at the sandbar and require a tow home.
the flywheel on a standard I/O is the exact flywheel used in a truck with a manual transmission. however why replace a flywheel when you can spend $15 at NAPA for a new ring gear.

it is heavier than the automatic flex plates without the torque converter, however comparable to a flex plate + torque converter

use the search function on replacing a ring gear. https://www.google.com/search?q=fly...HYlWDAgQrQIoA3oECAcQBA&biw=1569&bih=833&dpr=1
 

racerone

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It is that spinning torque torque converter that adds the weight on a car.----As stated above.
 

Ed Harris

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I got it now. You separate the ring gear from the flywheel and replace it with a new ring gear. I saw a whole replacement for $140 on Amazon and I didn’t know that you could separate them.
 

kenny nunez

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One other thing, be sure to replace the starter drive since it may have caused your problem. Be sure to get a new one and not one that was rebuilt.
 

Ed Harris

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When I first heard the metal snagging noise I took the starter off and had it rebuilt thinking that I was having starter motor trouble.
When I went to install starter that’s when I noticed some teeth missing. Everything will be easy to inspect once I pull the engine and get it on the ground
 

tank1949

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I had a bad console/helm switch that cause starter to drag and it ate the ring gear. NOT FUN. Something cause ring gear to wear out prematurely.
 

Ed Harris

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My starter may need to be shimmed so I will check the mesh when I get the new one on
 

Scott Danforth

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I got it now. You separate the ring gear from the flywheel and replace it with a new ring gear. I saw a whole replacement for $140 on Amazon and I didn’t know that you could separate them.
Rock Auto is $70 a steel billet SFI rated one is $150 from Summit Racing.
 

Scott Danforth

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My starter may need to be shimmed so I will check the mesh when I get the new one on
the main cause of ring gear wear is bad contacts on the electrical side of the starter. causes the starter to spin much slower, and the solenoid not to throw the bendix out fast enough so the starter becomes a mill and machines the teeth off.
 

tank1949

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My starter may need to be shimmed so I will check the mesh when I get the new one on
unless motor is out, there is not much room to do this. May be enough room on single engine application. At least, I haven't figured out how to do it.
 

Ed Harris

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Thanks for all the replies. Just about have engine ready to come out but I have one problem. The water inlet line to the power steering cooler is one hard joker to break free. Anyone have any good ideas?
 

Bondo

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Ayuh,.... Slip a hose pick in under it to pop it free,....

Try the other end if necessary,.....
 

Grub54891

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Hose pic and power tune. Get the pic in there and give it a shot of power tune in a couple spots. Easy at that point.
 

achris

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Thanks for all the replies. Just about have engine ready to come out but I have one problem. The water inlet line to the power steering cooler is one hard joker to break free. Anyone have any good ideas?
And this is why I put a thin smear of grease on all hoses before I put them on. I've pulled hoses off that I put on 20 years earlier, and they come off like they were put on the day before.

Chris.........
 

nola mike

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And this is why I put a thin smear of grease on all hoses before I put them on. I've pulled hoses off that I put on 20 years earlier, and they come off like they were put on the day before.

Chris.........
I've started doing this, esp on that same hose, which needs to be pulled for winterizing and is a pain to reach
 

JASinIL2006

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I've started doing this, esp on that same hose, which needs to be pulled for winterizing and is a pain to reach

Even better, add a drain valve to that hose. Then you don't need to remove it at all. That hose was always my #1 pain in the neck when winterizing. I added a drain to the hose and it makes winterizing so much easier.
 
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