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160 hp mr-1 engine swap (with jet ski engine)

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Not great pictures but I built a gantry out of 2x4s and 2x6s, it needed to be 10’ high and 10’ wide lifted the engine and pulled the boat out from under it. There really isn’t much to disconnecting the engine in order to pull it. You need to remove the coupler cover, all the wiring except the oil tank sensor simply unplug, the fuel line, exhaust, cooling lines, and throttle cable get disconnected and then the four bolts on the engine mounts.
 
@okula225 if you're still looking for a manual, I've got one for an 05. They are virtually identical boats, I've yet to find a difference between it and my 06. PM me if interested...
 
I built a gantry and used a chain hoist. I have removed and reinstalled the engine four times now and have it down to about 3 hours to remove and the same to install.

A standard engine hoist won't get it high enough. I tried :(.

Here's what I built.

Pm me @Jgorm if you want to go over how to get it done.
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I can pull it in about an hour by myself. Of course I am all setup for it and its way easier in a ar230. The only thing I need help with is removing the engine cover. Here is my setup.
 
So finally pulled the engine out of the boat, it was much easier than I thought. Completely tore down the engine and found the problem. Failed journal bearing on cylinder no 4. Crankshaft journal looks clean but the sidewalls of the crankshaft where the connecting rod rubs up against isn't the cleanest. Any thoughts on this? Can that be cleaned up or am I looking at a new crankshaft?
 
@okula225 Out of curiosity, were the cooling system water jackets without sand/sediment buildup. My cylinder water jackets were packed with white algae.Cylinder water jackets
 
Thanks for the update and pictures, especially about the cooling passages

Do you know how many hours are on the engine?
Was it fresh or salt water boat?
What did the thermostat and anode look like?


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Thanks for the update and pictures, especially about the cooling passages

Do you know how many hours are on the engine?
Was it fresh or salt water boat?
What did the thermostat and anode look like?


.
About 400 hours and it was a salt water boat, but flushed after each use.
Didn't pull the thermostat but now that you mention it I definitely will.
 
Can you take a picture of the end of the exhaust (the long J shaped one)? There are 3 holes that allow cooling water to enter the exhaust steam. There have been reports these clog with salt.
 
Can you take a picture of the end of the exhaust (the long J shaped one)? There are 3 holes that allow cooling water to enter the exhaust steam. There have been reports these clog with salt.
Mine are free and clear, however there is a lot of salt build up around the rubber joints that I will have to clean, however the 3 holes on the 90, j, and small pipe are all clear, I will be passing some brake parts cleaner through it though to get ride of any potential debris.
 
Do you have a micrometer to measure the crankshaft journals? I would recommend being very picky about tolerances with those journals, 10,000 RPM is no friggin joke. As for the sides, different engines have different tolerances. Some engines have enough clearance to where the rods will "float" back and forth a little. I wouldn't be too worried about a design like that, but I get the feeling this might not be the case here. My question would be what caused the marring? Do the bearings have a flanged portion that rides the side, or was it the actual connecting rod that rubbed the side of the crank journal? Overall, I would like to believe that the sides of the crankshaft journals won't be too critical, but words like that are relative to who's talking, and who's listening...lol. I would be freaking anal about the journals themselves, though. Pics would be beneficial too...
 
Picture 1 is a good crank journal.
Picture 2 is the damaged crank journal.
Picture 3 is the good journal bearing.
Picture 4 is the bad journal bearing.
 

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Do you have a micrometer to measure the crankshaft journals? I would recommend being very picky about tolerances with those journals, 10,000 RPM is no friggin joke. As for the sides, different engines have different tolerances. Some engines have enough clearance to where the rods will "float" back and forth a little. I wouldn't be too worried about a design like that, but I get the feeling this might not be the case here. My question would be what caused the marring? Do the bearings have a flanged portion that rides the side, or was it the actual connecting rod that rubbed the side of the crank journal? Overall, I would like to believe that the sides of the crankshaft journals won't be too critical, but words like that are relative to who's talking, and who's listening...lol. I would be freaking anal about the journals themselves, though. Pics would be beneficial too...
So I reached out to my very trusted car mechanic and he advised that in the current state of the crank that if I put everything back together with new journal bearings, that he would be surprised if the engine lasted more than 10 minutes. Not shocking based on the gouging.

My plan is to take the engine to a reputable jet ski mechanic (and crankshaft machine shop) and have them polish the crankshaft journals as well as sidewalls and use new journal bearings that account for the polishing delta off the crank. I know what to do, however don't have the tools to do so, so better off leaving it to the pro's.

Outside of that, do you think reassembly and timing is very difficult? Been toying with reassembling it myself, new gaskets, and able to clean everything to ensure no metal shavings throughout the entire system. Biggest concern is ensuring TDC, as well as intake and exhaust cam positioning to ensure timing is correct.
 
I can't look to find it now but check @Jgorm posts, he did a complete rebuilt and posted a bunch of great pics.


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I can't look to find it now but check @Jgorm posts, he did a complete rebuilt and posted a bunch of great pics.


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Just found his two videos, very helpful. Makes a lot of sense, cylinder 1 at TDC and the cam dots aligned with the alignment mark. Very confident in my abilities once I get the crankshaft repaired.
 
@okula225 Was the piston above the scarred journal somewhat seized?
 
@okula225 Was the piston above the scarred journal somewhat seized?
No, there are no gouges in the cylinder wall, just seems that the journal bearing rubbed against the crank shaft wall and caused it to seize.
 
Wow, am I seeing right that the bearings basically melted out the side to create the “flanged” portion on the two bad bearings? I’m not seeing a flange on the two good bearings... Whether you get this crank turned down, or buy a new one, I’d also recommend getting the whole assembly rebalanced. These buggers spin pretty quick, and I’m sure the factory balanced them. I reserve the right to change my mind, but unless you’ve got a crankshaft thrust bearing that went out, I can’t quite envision how the connecting rod would’ve been the reason it wore on the side of the crank journal. I’m wondering if that damage wasn’t done by the melting bearing as it squeezed out between the rod and crank.
 
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