[StinkerBean]

Picked up this 2002 Yamaha Kodiak 400 4x4 for free. My buddy's neighbor was getting ready to haul it off to the dump. Asked him what's the deal with it and he said had been running fine and then one time he went to start it and it would turn over a bit and make a clicking sound coming from under the seat which I believe is the solenoid and couldn't get it to start. After that it stayed parked for about 2 years outside. Said he didn't have time to mess with it.

I got it home but didn't have a battery for it. Tried connecting my battery jump pack to it and see if anything would happen. With the key on no dash lights or headlights came on. I tried jumping the solenoid but just sparked a couple of times. Figured I'd try to turn the engine over by hand next.

The internals of the pull start are missing so I removed it to get to the crankshaft bolt and removed the spark plug. Put my ratchet on it and it wouldn't budge at all, not one inch. Feels completely locked up. I tried filling the cylinder with WD40 for a few hours to see if it would help but no luck. I added some marvel mystery oil into the cylinder and let it sit overnight and still no help.

I decided to remove the starter and make sure it's not locked and it spins freely. I removed the crankcase cover to see if maybe something looked broke back there but all looked good. At this moment I plan on letting the mystery oil sit for about a week and see if it frees up anything which I doubt.

Without have to tear into the engine do any of you guys have any tips or tricks on what I can do to try and get it unseized?

 

[pyromedic]

There's a few things you might try, none of which may work. I think I'd start from the least possibly damaging and move toward things with a greater possibility of damaging parts. The first thing I would have tried is looking into the cylinder through the spark plug hole with a bore scope to see how much rust/corrosion was visible but since there's already been WD-40 & MM Oil in there a scope may not reveal much at this point. You might try adding some kerosene to the MM oil already in the cylinder. Kerosene is quite thin (low viscosity) with little surface tension and can work it's way into small places carrying oil with it. Let is sit a few days and try turning with a breaker bar. You may be able to pump HOT water through the water jackets which would expand the cylinder diameter slightly and allow oil/kerosene to reach even more areas. Try turning it over while hot. Sometimes rocking back and forth (clockwise & counterclockwise) can break things free. If none of that worked you might try applying air pressure to the cylinder if you are lucky enough to be in a portion of the cycle to have both valves closed and the piston not at exact top dead center. High air pressure may force it over and at the very least may force some lube to areas between the piston, rings and cylinder wall that haven't yet received any. If there was moisture in the cylinder it's likely the rings have rusted. When steel or cast iron rust they expand reducing clearance sticking things in place. You might try pouring some Evap O Rust into the cylinder in an attempt to dissolve any rust but with all that oil in there it may no longer be able to reach the areas it needs to reach. Sometimes a little shock or vibration can be helpful. Gentle use of an impact wrench to try to turn it over can be attempted but don't get carried away. It's possible to break crankshafts or strip fasteners you are using to attempt rotation ultimately destroying an otherwise good part.
In any case, if things are rusted/corroded that bad it's highly likely that you'll need to do a top end job before it will ever run well.

 

[StinkerBean]

Thanks for all the advice. I used a shop vac and removed whatever WD40 that was in there. Then I poured in some MM Oil and has been sitting for a couple of days now. I might try adding some kerosene like you mentioned and see if that helps. Also read that Kroil is good to use and also a 50/50 mix of ATF and Acetone. I'm willing to try whatever just to see if I can get it broke free without having to disassemble it. At that point I'll just put it up for sale for parts and get me some beer money.

 

[StinkerBean]

Well I gave it another go. I couldn’t move it with just the ratchet and socket so stuck a breaker bar in there and gave it a few taps in both directions with a mallet and it broke loose. I can now spin it over.

Should I fill the cylinder with some PB blaster and let it sit for a couple of days before draining the oil and putting in new oil? Or is there something else I should do? Any other steps to take with it before trying to actually crank it over?

 

[JBRanger800]

What I would do. Raise whichever end of the machine to make the cyl vertical as possible. Put some oil in cyl ., Leaving spark plug out. Turn over by hand a few times. Then take a drill with socket on crankshaft nut and spin it over for several minutes. Then suck the oil out of the cyl and try to start it after reassembly.

 

[pyromedic]

Glad you got it broken loose. JB Ranger's idea is a good one. It can't hurt anything at this point and who knows, you may get lucky and have it run fine.

 

[StinkerBean]

Thanks fellas. Will report back once I get more done with it.