1995 Mariner 115hp 4 cyl 2 stroke- Seized

skytracker

Seaman Apprentice
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Apr 11, 2008
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39
This motor started fine after storage but telltale was not as strong as it should be. So went to shut it down and check impeller out. It would not shut off until I hit the kill switch and shutoff fuel. Water pump housing had grooves, seals damaged. Impeller stiff but intact. Replaced all. Tried to start and would not crank. Found shift in gear interlock thinks motor is in gear yet prop spins like neutral. Found out from dealer QS 3000 controls and cable failure recall applies. Dealer replacing controls and cables. Try to start and still locked up. Pulled plugs and tried flywheel no go. Dealer borescoped and said no damage evident in the cylinder area through the plug holes that it must be in lower part of power head. Also tried again with lower unit off still stuck. I need to get it home and get the service manual to tear down and inspect what it could be the dealer wants a lot to tear down further. Any help pointing in the right direction is appreciated. This motor has been well taken care of and stored in my workshop barn in winter.
 

skytracker

Seaman Apprentice
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Apr 11, 2008
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39
Looking at rebuilding but I need to get in there and see what I have going on. What is the easiest access to the crankshaft, connecting rods, and bearings??
I think I can get access to the cylinders through the exhaust/cooling cover with all the thirty bolts on the left side, correct??
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,030
Removing the exhaust cover will allow you to look at the pistons and rings through the exhaust ports.----It will also allow you to see if one of the cylinder sleeves has moved.---That would be serious trouble.
 

skytracker

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Apr 11, 2008
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Racerone thank you for the confirmation. I hope none of the sleeves have moved. What about access to the crankshaft and bearings??
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,030
That would require removal of powerhead and a complete teardown.--------Not hard to do.
 

skytracker

Seaman Apprentice
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Apr 11, 2008
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39
My serial number is 0G272245. I have a PDF of the service manual somewhere but I cannot find it.
 

skytracker

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Apr 11, 2008
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Thank you Racerone. I am,supposed to get it back tomorrow. I intend to take the powerhead off. Do I need the special stand to put it on?
 

skytracker

Seaman Apprentice
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Apr 11, 2008
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39
With Memorial weekend going on I just got the boat home. I will start taking the powerhead apart tonight to see what I find.
 

Drew220

Seaman Apprentice
Joined
May 30, 2016
Messages
39
Good luck. I have a 95 125 Mercury which is almost identical to yours. I used a engine hoist to take the power head off of mine. It's relatively flat on the bottom. I would sit it on a table still connected to the hoist. You will need new manifold gaskets. I would recommend using gasket remover to remove the old gasket. It was a huge pain to scrape off.

Wish I would have known about the QS 3000 recall. Mine broke last year.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,589
These motors are bad about cracking/breaking pistons skirts if run above recommended RPM range....
 

skytracker

Seaman Apprentice
Joined
Apr 11, 2008
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39
Good to know Faztbullet. I don't think I ran the RPM too high. I have the cooling cover off and will get the exhaust cover and more on the weekend. Have to get my hoist set up moved so I can pull the boat forward when I pull the head off.
 

skytracker

Seaman Apprentice
Joined
Apr 11, 2008
Messages
39
Drew220 what did you find on yours when you tore it down? Did you repair it?

You may still be able to get a dealer to replace the QS3000. They just did mine free of charge for the control, cables, and labor for it and initial engine inspection. But they would have charged too much for the powerhead tear down and possible repair.
 

skytracker

Seaman Apprentice
Joined
Apr 11, 2008
Messages
39
What about hydraulic,lock somehow? So far,I cannot find anything except it is locked up. Can move the flywheel about 1/4". Cylinders look good. Will have to take the other half apart.
 
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