hit a roadblock.

[ottawa rogue]

I pulled my 450 out of the garage to start working on it and looks like the engine is seized. I tried to spin it over with a breaker bar and no go. I've got a ton of light oil down the spark plug holes but i'm not hopeful
So looks like it's time for an engine

is there any special things to look for as far as the motor locking up?
I know some yamahas have a problem with seizing the cam and locking the motor up.

 

[Guest]

Hi ottawa rogue.

What is the story behind that bike?

Have you ever seen it turn or run? I mean has it seized during the winter? Or you bought it untested and an unknown quantity?

 

[ottawa rogue]

well.... it was given to me instead of labor for fixing a guys virago, so if i scrap it out i've lost little or nothing.
the PO stated that it sat for a couple of years, but it ran when he parked it.
so i guess you could say that it was an unknown. Worst comes to worst, i'll tear it apart over the winter.
right now i'm in the process of buying a house, so that's gonna figure in to things

 

[Steve]

Did you pull the spark plugs before trying to turn the engine? If a cylinder is full of fluid (water, gas, whatever),it can hydro-lock, not allowing movement. Removing the plugs will allow the fluid to escape.

You say you have some oil in there now, just not sure when you tried turning it. You can also try rocking the crank a bit. It's generally not good to turn the engine backwards, but you only want to try turning it a few degrees, just enough to see if you can break the rings free.

.

 

[ottawa rogue]

ya, i pulled the plugs and looked down the bores as far as i could see. there wasn't any liquid down there. I dumped in some marvel mystery oil and let it sit.
i tried moving it at the stator end of the crank, and it felt like it wanted to move a little, i'll try again tonight.
I priced out an engine at our local motorcycle scrapyard yesterday, they want $650 if they have it there, $850 if they have to find it plus shipping
so needless to say i won't be doing that. bike's not worth it

 

[Guest]

http://www.thegsresources.com/_forum/showthread.php?230239-1978-GS400-Parts

There's a GS400 engine for sale for $100 at the link above. I think it might be an easy swap for you, give it a look.

Btw, I wouldn't automatically assume your motor is seized based on what you've described. At the very least, I'd be inclined to remove the head and cylinder and determine the cause of the problem before making a snap judgment.

 

[ottawa rogue]

Update: I got it broke free tonight, but it's still probably need to be gone through. I did notice that the starter gearing seems to be dragging on the ring gear behind the rotor.
this seems to be a fair amount of the drag. I'm going to bring my borescope home tomorrow night and see what the insides of the cylinders look like. I could see what looked like the factory crosshatching through the plug hole.

 

[ottawa rogue]

Got the bike running this morning, after a misadventure with the oil drain plug. the old oil was loaded with rotten gas, and the carbs need to be gone through (I figured I'd have to do that anyway)
We're making some progress now.

 

[C_OUELLET]

I see you've figured it out! My Gsx400L wouldn't turn over, thought it was seized up and all until I popped off the gear lever and that chain cover. my chain was all messed up and jammed up in the sprocket! Just thought I'd post that in case anyone ever runs into that same issue.