YeeHaw33

I just recently got a 1977 JS440. This was given to me for free (wow), so I didn't ask many questions. I just got an owner's manual on ebay, but I have an oil question that I do not see the answer for.

There is a black oil plug at the end of the engine, no dipstick, just a plug. I'm not sure what type of oil to use here. Can anyone help with this? Thanks.

atc250r

I'm not too familiar with the Jet-Ski engines but 2 stroke engines have the oil pre-mixed (or on newer machines injected) into the fuel. You shouldn't have to add oil to the bottom end ever.

John

no fear here

The black oil plug that you refer to is not on oil plug at all. Don't put oil in there it is actually a service plug for the ignition system. All the lubrication for your motor is in the 2-stroke oil.
Congrats on the good deal!!!

YeeHaw33

I understand that the mix provides the oil, but I just looked at it again, and this cap has oil residue on it and also an o-ring. It almost looks like it's at a crankcase. It's at the very end of the engine, right next to the fuel tank.

no fear here

Trust me on this. I first checked in my service manual before replying to your question. I own 650's so I wasn't positive, but I was pretty sure about it. Take a flashlight and look into the hole. You will see the flywheel in there.

jonesy54

yes, the hole is for ignition and timing adjustment purposes.

you'll be sorely dissapointed if you put oil in there.

__________________
-1990 X-2 - the weird one
-1987 JS550 - bone stock and staying that way for now
-1984 JS550 - restored, 440 pump, Skat Trak, primer, thumb throttle

YeeHaw33

Thanks guys, I appreciate it!

JUST-IN-TIME

if u see oil in there, you got a crank seal problem

__________________

HUMAN BUILT = HUMAN FIXED

goldfish

So what happens if you do put oil in that plug? The guy I got my skis from said that he ran amsoil in them... and if there is no oil that should sit in the crank of an 86 550, would you really mix amsoil with the gas?

jonesy54

it probably depends on how much he put in there...or he may have mixed it with the gas, who knows? POs are hard to figure sometimes.

heck, i have mixed regular motor oil with my gas a couple of times when i was out of the 2-stroke stuff.

__________________
-1990 X-2 - the weird one
-1987 JS550 - bone stock and staying that way for now
-1984 JS550 - restored, 440 pump, Skat Trak, primer, thumb throttle