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Yanmar Locked Up

R

rover4679

Adam Scarbrough
Anyone ever seen or heard of a 3 cylinder Yanmar locking up while sitting up? The motor was run 3 months ago with no issue. Today I tried to crank it and it sounded like the started as hung up. I tried to turn it over by hand with the hand crank lever and it will NOT budge. Any ideas??
 
What does the oil look like? Are the batteries up to crank the engine? I am not sure if you can crank by hand, I cannot! It's not in gear is it?

Just thoughts.
Jim
 
Sounds like it is water locked. Pull the injectors and crank the motor. If water shoots out, you have a manifold gasket leak.
 
if it's locked up because of water in the cylinders try draining the waterlift muffler and see if that frees it up. I've had water siphon back to the engine when the anti-siphon valve stuck.
 
Adam--since no one mentioned it, I have to assume you tried to move the crankshaft with the Compression Release Valve open? If there was water but the crank/cylinders are not frozen by rust, the starter should be able to turn over the crank and expell any water out the valves-- with the compression release open. But if even then you have no movement of the crank, I think somehow the crank is frozen.

There is a tech named Rick at Mack Boring, people in NJ who rebuild the Yanmars. (He did mine is 2009) His phone is (908) 391-1713, and he knows these engines through and through. Maybe he'll take a call from you..just to ask if there are other diagnostics you can do before calling in the Doctor. The number at Mack Boring Co is (800) 622-5364.

I hope you find an easy solution; maybe the Bendix is jammed, and it's a starter problem, that would be a lot easier than water in the engine...

Good luck!

Carl

PS Only once in 30 years was I able to start the 3QM30 using the hand crank, and it took two people--one to turn the handle as hard as possible and another the close the compression valve, at just the right time: as the cranker was pulling up, his strongest point, so he can keep pulling up as the first cylinder compresses. Otherwise the crank is stopped instantly, no joy.
 
I tried to crank it with the compression release down. It will not budge. The crank will not move at all. I drained the oil through a t-shirt and its slightly dark but looks and smells good with no metal or flakes. The oil had gotten to the top of the motor as indicated by oil in the rocker arm bearings. The gear box is in neutral and turns free.It looks like the motor is going to have to come out. (Unless my phone call to Rick indicates otherwise). Any hints for easy rig up to get it out?
 
Are you sure the batteries are up and starter is getting juice and is not bad? Another idea, why not remove the injectors and squirt in some light weight oil and let stand if the starter is okay? I would exhaust all efforts before pulling the motor.
Jim
 
I agree, pulling motor is drastic/last resort when you are KNOWN to have a frozen motor. Even then maybe they can do something with the head off. Call in a Doctor before you do pull the motor, it is not simple-- requires outside help with fork lift or similar. Rick or Mack Boring will know where there is an engine guy near you wherever you are.

Please try to find out what's wrong before you pull the motor.

Best luck!

Carl
 
Did you try draining the muffler or removing the exhaust hose from the gooseneck, If there is water in the cylinders this will drain it out. I doubt you can drain the water by the compression release levers.
 
I pulled the injectors and ran a plumbing snake into the cylinders. No water but a little rust. I poured marvel mystery oil in each cylinder and said a prayer.........we will see.
 
Only other thing I can think of now that you are injecting stuff in there, try a rust-breaker called PB Blaster --it really truly works to loosen rusty things. Maybe pour/spray some of that in after the Mystery Oil?? It is very non-viscous and will penetrate everywhere. It will clean out when the fuel comes in again

Maybe time for a mechanic

Carl
 
Well, its free. I filled the cylinders with MMO and made a little t handle on a pipe that would bind into the flywhel so that I could put a little pressure on it with a hydraulic jack. Every 12 hours I flipped it to apply pressure in the other direction. Today I came home to a loose jack. I worked it back and forth until it freed up. (It took a while). Anyway, its free and I ran a bendable magnet along the cylinder walls and found no metal. I guess the lesson here for me is to run the motor longer than 5 or 6 minutes and run it more often than every 3 or 4 months. Thanks to all that posted.

P.S. Carl, Rick is the one that convinced me that this motor is a beast and to keep trying until I got it free. Thanks!
 
Way to go and I think we all learned something! the hydraulic jack idea was clever and forceful! (more than resourceful)

I assume the rings will clean the cylinder walls and I wonder where the junk goes, but wow you did it. I hope it all cleans out.

And so glad Rick was a help to you!

Keep turnin over; your patience is admirable.

cm
 
I do know that there are "layup" instructions in the Nigel Calder's book that assist those who store their boats for long periods of time.
Jim
 
It starts right up and runs great but I now have a little leak on 2 of the injectors that tightening didnt solve. I pulled the injectors out but want to change all of the gaskets in each of the 3 cylinders. Has anyone pulled the middle and bottom piece that is down in the injector hole?

Thanks,
Adam
 
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