Hi all,
My crankshaft pulley got loose and as i result my timing belt jumped out of it this weekend.

Does anybody knows how to properly adjust the timing between the cam pulley and the crankshaft pulley?

Thanks in advance...

Lucas

Hi there, I have never heard of this problem on these motors. The belt pulley on the crank should be fixed with a large nut which has a lock-tab washer on it to prevent it from loosening.
In any case, the timing is set via the flywheel and cam pulley. Align the "T" mark on the flywheel to the index mark you will see on the post under the rear bolt for the recoil starter (have to remove recoil to see it). At that point with "T" aligned with the mark, there is a dot / dimple mark on the outer edge of the cam pulley - that needs to be aligned with a corresponding dot / dimple that is cast into the top of the cylinder (or cylinder head, I can't remember) right under the edge of the pulley.

Good luck. Be sure the belt is tight and isn't stretched or cracked, that sounds like a more likely culprit. It would be very unusual for the crank pulley to loosen unless somebody messed with it and didn't get it back together correctly.

Thanks John,

I bought the motor used, and yeah, someone fidled with it for sure before it got in my hand...

The locking washer is barely destroyed from all the vibration it received from being loose all that time... I'll put some lock tight in there... so it doesn't come off again.

Do you think that it could have messed my valves or anything while the timing belt got off?

THanks again.

Lucas

Lucas,
It could have damaged the valves, I think there is a potential for pistons to smack the valves in this engine if the timing is off, but it would have to be off more than just a couple teeth.
If you have very little or no compression when you get it back together with the timing correct - you may have bent valves. But before you decide the valves are bent, check the valve clearance too. If the valve clearance is too tight or there is no clearance, that can cause a loss of compression too.

Good luck.
John

Hi John,
I wasn't lucky at all, both pricier exhaust valve were bended.

Since I know that the previous owner already fiddled in some ways with the motor before, I'm wondering if it was already bended or if they did so as a result of my timing belt getting off.

I have ordered all the parts needed and a new head gasket as it broke when I opened up the motor.

I'm still not sure of which mark to align when I'll put it back. there is a dot on the pulley of the cam which I assume is the mark that I need on that part but I don't really understand what is the mark on the fly wheel. there is three larger dot stamped/drilled on the flywheel but I think it is more like a way of balancing the wheight of the fly wheel than to mark it. WOuld/could it be the woodruff key that act as a mark? but then it is a nonsense since you can't see it when the motor is fully built back together???

I Have to say I have a way better understanding of mechanic in general since I own this outboard but the timming is a bit out of my league....

thanks in advance!
Is there a way to post pictures in here?

Lucas
Lucas

Hi john,
Ok, I just got the T mark, it is written a really small t, between two dashes and then there is a F stamped on the fly wheel...getting there slowly. Is the mark on the recoil starter the hole right next to the bolt holding it?

thanks!

Ok, I understood all you said now...
Weird, on one of the post of the recoil starter, the rear post actually, a hole as been homemade drilled to see the T mark on the fly wheel.

As I suspected, the previous owner obviously fiddled with the motor.

Thrilled to build it back, I'm barely sure that it will gain some power in some ways....I'll post info in here as soon as I finish the repair!

Thanks again John for your precious help.

Good. I don't know if you can post pics here. I could take some and try it. Let me know if you need more help.