Is my motor F@#ked

[D-Nice]

Ok so last September at the brigantine beach bash I landed wrong an broke my tibia and fibula in my right shin, 2 surgerys 3 casts etc.. . My sj has been sitting since with a cover on it in my back yard... Open it up for the first time today an the hull had water almost up to the crank shaft.. Pulled the plugs an they look like there's moisture in there since there corroded.. What are the odds my motor is filled with water? It's not seized as I can turn the shaft by hand

 

[Little_Franny]

Unfortunately you prob have a condensation issue, if the hull sat with water in it the moisture gets in the air and then into the engine as the air heats and cools. If it wasn't fogged I would prob disassemble and inspect

 

[Sparkplug]

99.9%

 

[SVTPete83]

Hopefully your flywheel and bendix isn't rusted either. Good luck op. In the very least I would disassemble and re gasket.

 

[DAG]

If it's a stock motor Run it till it pops. In the mean time keep an eye out for a couch doner to swap in at your convenience.

 

[102nd7]

I agree with dag. Fog it turn it over by hand a few times and run your oil ratio 40:1 for a tank or two. You really got nothing to lose by giving it a go.

 

[Kny21]

I'd pull the top end and inspect. If you find you have issues it's gonna be cheaper than running it till it blows and possibly taking out the cyls and/or cases.

That's my .02.

 

[jetpilot36]

just run it. if its got a little water in it, you're gonna wanna get it started asap. if its a stock motor, just run it. i wouldnt go disassembling it unless it doesnt start.

 

[Sparkplug]

Crazy. It takes a hour to get the motor out and apart. Another hour to clean, and 1 more to put it back in. 3 hrs of work to potentially get 100s more hours of ride time.

Don't be a lazy fawk, take it apart and clean it.

 

[jetpilot36]

Crazy. It takes a hour to get the motor out and apart. Another hour to clean, and 1 more to put it back in. 3 hrs of work to potentially get 100s more hours of ride time.

Don't be a lazy fawk, take it apart and clean it.

is your motor all o-ringed or something? cause you're looking at exhaust and headgaskets and intake gaskets and timing cover gaskets to take a motor apart and clean it. it takes me at least an hour to get the surfaces all clean for new gaskets. then you gotta shim the motor and make sure its lined up right. its more than just a "clean it in an hour job"

 

[JetManiac]

That isnt good, most likely rust in the bore and rings as well as pin bearings and crank bearings. Depends how much moisture for how long.

You can remove your head and intake mani to inspect crank and bores to at least get an indication.

You can oil her up and run it for without issue ,but you may also throw a rod after bearing failure and ruin cases and cylinder.

 

[D-Nice]

Since it's a jetmaniac 781 with litterally maybe 5 hours on it I think I'll jus take it apart an go over everything.. Thanks for the input guys

 

[jetpilot36]

ok. well youve probably got more than a grand into that motor then. i would take it apart to be sure. if it was a stocker, I'd just beat it like morning wood!

 

[Sparkplug]

I wrench so I have proper tools. Air tools. A mini impact driver is a blessing with these also Small wire wheel on a die grinder cleans and preps all surfaces very easily. If you know the torque specs n your head, that saves a bunch of time also. Yu can reuse the cylinder base gasket, and exhaust gasket. The flywheel and case gasket can be yamabonded.

If your engine ever sits for a length of the with water in it, disassembly is probably your best bet. Yes these engine are tough and can take abuse.

 

[yamanube]

Just run it, is probably the worst advice I have ever heard. Even a stock motor that has been sitting under water for a year should be disassembled and inspected.

 

[SuperJETT]

Also, 'what have you got to lose?', quite a bit since a crank can take out the crankcase, cylinder, bendix, etc.

 

[102nd7]

In my opinion the 61x/62t 701-771 motors are so cheap and easy to come by it isn't worth the time or money to disassemble and replace parts that may or may not be broke or damaged. Heck he doesn't even know of there is water in there or not. I'd drain the waste from the hull pull the plugs and turn it over a few times to see if any water is in there. It doesn't really matter tho. He already said he was going to take it apart.

 

[Roseand]

Cheap? Hahahahaha. What's it gonna be, less than 100$ to replace all the seals and gaskets if he strips it down and inspects it? A jm 771 is worth well over a grand, so I sure as hell wouldn't just run it till it blows. It's not unheard of for a crank to go and take everything out with it. I'd say check it out. Still 102nd7,cheap? Lol even if he were to replace pistons, rings, all new gaskets, rebuilt crank for about 350$ or a sbt crank for 250$ and a hone, he'd be well below the cost of a new jm 771..

 

[102nd7]

Oh come on now. Half of you wouldn't follow your own advice on this.

 

[jetpilot36]

I think he means chep compared to after market. Ive seem 701s and 760s for 4 5 and 6 hundred dollars. That is pennies compared to what we all want to be running which are 3 and 4 thousand dollar motors. If his seal at the starter is good, I bet There's condensation in that motor at worst. If it is a jm motor, then all his seals should be good right? But ideally the gold standard would be a full inspection which will require ordering gaskets and tearing it down.