Another 454 flywheel ring gear shot

mf15

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Great forum I have read all of the ring gear threads. But need some help.
1993 Baja 236 cuddy 454,carbed,thunderbolt,Bravo 1.
Son bought boat in december after a test drive it worked. Was re winterized, We let it sit and started to work on it in February.
Pulled plugs, water ingested into two cylinders, replaced manifolds and risers, got rid of the water and oiled cylinders, There was some rust and of course the water had froze in the cylinders over the winter.
Tried starting a few times last week, the engine turned over ok, quite a number of times but did not get a start. Then the starter started screaming and not turning the flywheel. Pulled starter and sure enough broken teeth on the ring gear, starter bolts were also a quarter to half turn loose,possible streatch. When bolts were pulled there was also some metal fines on the threads. It will cost 1200 to pull engine and replace flywheel. Of course shop says have to replace whole flywheel and not just the ring gear.
I guess my question is why did this happen. Tight engine from the slight rust on cylinder wall. Dont want this to happen again. Engine is not seized you can also turn it over with a wrench.
What might we be looking at for additional cost. cylinder honeing new piston/rings. anything else. We are also going to have them pressure test for cracked block.
The 10000 boat will now be a 13000 boat after this is done and the trailer brakes are replaced. Thanks for any help Old Mike
PS: I told him to buy a boat with an outboard, oh well.
 

Bondo

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Re: Another 454 flywheel ring gear shot

Pulled plugs, water ingested into two cylinders, replaced manifolds and risers,

My Guess is,.......

This issue was going on Before the sale of the boat.........

Of course shop says have to replace whole flywheel and not just the ring gear.

I'd find Another Shop to do business with,.......

Why would you spend Hundreds when it's a $30.00 Part,..??..??.......
 

mf15

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Re: Another 454 flywheel ring gear shot

The other quote for the job was 1800.
Anyhow I guess we could pull the engine, lift it out with one of his bobcats it only weighs 1200 pounds with outdrive, not sure what the engine weighs by itself. But it looks so complicated in there, we are not mechanics, but reading this forum it seems like you become one fast, if you own a boat. But since I dont really know that much about engines/outdrives at least this time I would rather have a shop do the job, and figure out what actually caused this.
The manifolds were shot so my guess is that is where the water ingestion came from. Also on that one cylinder we have lower compression, 105 PSI.
Have the merc service manual but the more I read the more complex the job looks. Yes it is a 30 dollar part, but from the other threads the boat shops only want to relpace the whole flywheel for some reason as does ours.
Old Mike
 

Bondo

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Re: Another 454 flywheel ring gear shot

Well,........ Boat Mechanicing IS Easier than Car Mechanicing........

To Pull the motor,..... There's a Few Wires,... A couple of Hoses,+ 4 Motor Mounts......
It's Pretty Straight Forward..... especially with the Manual......

I'd Pull it,+ replace the ring Gear,........ Then Run it.......

If it's going to be an Issue with the lowered Compression,....
You might get By, til fall,+ you could do an Engine Overhaul next Winter........
 

whywhyzed

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Re: Another 454 flywheel ring gear shot

I can't think of a reason to replace the flywheel. It does sound like you'd want to take the heads off while the engine is out and look at valves and cylinder walls, rear coupler, pressure test outdrive and such. It seems with these older boats, you go one of two ways to really enjoy it. Either you become your own mechanic, or you have to be in a position where you do not care at all what it costs to run it, you find the best shop you can and get them to just "deal with" the issues and have it idling at the dock every Saturday morning for you and fix it back up next week.
 

mf15

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Re: Another 454 flywheel ring gear shot

No son does not have unlimited money that is for sure. I just re-read the shop manual on pulling the engine. Pull outdrive, then disconnect everything.
Then you have to re align the outdrive and reconnect. My problem is I do not know what caused this. So this time probably need a pro to make sure it does not happen again. I would hate to replace ring gear and strip it again the first time the starter was engaged. You would think that if you can turn the engine over by hand then it is not too tight. But I am not 100% sure on that. That is why I am asking here so I have at least an idea on why this might have happened. When it was cranking we pulled the plugs on the water ingested pistons and no water came out. Old Mike
PS: About 250-300 hours on the boat but of course it is 14 years old.
 

Bondo

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Re: Another 454 flywheel ring gear shot

That is why I am asking here so I have at least an idea on why this might have happened.

And the Answer Is,...........

Pulled plugs, water ingested into two cylinders, replaced manifolds and risers,

Rotten Manifolds will Do It Every time.........
 

mf15

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Re: Another 454 flywheel ring gear shot

Not making myself clear. Manifolds are fixed, so why did the ring gear teeth get chewed by the starter. I am thinking tight engine, but it can be cranked by hand. Even if it can be cranked by hand could it still be tight enought to chew up the ring gear., and if it is tight what might be the reason.
Old Mike
 

mf15

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Re: Another 454 flywheel ring gear shot

Update: Checked flywheel it only has one spot eaten away. Put starter back on and it only took about 1 second or less and and engine fired right up.
So I guess it is not overly tight, engine sounds fine so far, no leaks on the outside of the new risers and manifolds. Too bad still need to replace flywheel/ring gear. Old Mike
 

Don S

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Re: Another 454 flywheel ring gear shot

Not making myself clear. Manifolds are fixed, so why did the ring gear teeth get chewed by the starter.

The engine probably hydrolocked before, damaging the teeth on the starter and the ring gear. As long as the starter misses the bad spots when first trying to start, then it will usually work for a while. But, it will not heal. The problem is still there........... and will get worse.
 

Coors

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Re: Another 454 flywheel ring gear shot

But it will come back to haunt you; that engine always stops at 120 degree positions, is the nature of the beast. So you always have a 33.33 % chance of it wanting to start where there is no tooth...
 

Bondo

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Re: Another 454 flywheel ring gear shot

Not making myself clear. Manifolds are fixed, so why did the ring gear teeth get chewed by the starter.

Don answered this,+ I thought I did earlier,....

It No Doubt started this Issue,... Before you got the boat,....
The Previous Owner just didn't Tell you about it......
With the New Manifolds,+ Risers,.... You Should have this thing Behind you......

'Course..... You Still need a New Ring Gear.........
 

mf15

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Re: Another 454 flywheel ring gear shot

Thanks guys, I understand now. Pulled the plugs on the two cylinders after running for about 15 minutes on muffs and cranked it, no water came out.
So hopefully the manifolds and risers were the cause of the water ingestion.
I know the flywheel is shot, and needs replacement, but it was good to see
that the engine now seems so far on muffs to run fine. Need new starter bolts
after looking closely they were slightly bent,from the stress. Probably also new bendix or starter just to be sure. Thanks again. It would seem that these complex old boats are a never ending maintenance nightmare.
In the good old days my 25 horse pull start Johnson $250 bucks for the boat and motor was the way to go. But that was 45 years ago, I was about 14. Did lots of fishing out back in Brigantine NJ, the thing ran until I was about 26.
It was an old engine when we bought it. Old Mike
 

Coors

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Re: Another 454 flywheel ring gear shot

That engine always stops/starts in 3 positions of the flywheel. Replace the ring gear.
 

Coors

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Re: Another 454 flywheel ring gear shot

and make sure that the forward- mounted bracket is installed. It saves the stress on the 2 starter bolts.
 

Bondo

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Re: Another 454 flywheel ring gear shot

Need new starter bolts
after looking closely they were slightly bent,from the stress.

Ayuh,.......

Get the Chevy style 1s,.....
They're Knurled along the shank of the Bolt,+ they Fit the Starter Much Better than the aftermarket Smooth shanked bolts.......
 
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