03 nissan 18 hp 2 stroke spinning out or clutch slipping?

[willys_truck]

This is my first post, I am needing a little help with my 2003 nissan 18hp 2 stroke outboard. The engine is on a 1542 war eagle boat (rated for a 25), The engine runs and idles great, but when I go to take off and plane the boat out it spins out and just revs up. If I ease into the throttle, it will go into to plane and run fine, as long as I keep the boat on plane it is fine. It just spins out or slips when trying to get to plane fast. I thought my prop (10 pitch) might not have enough pitch, so I bought A new stainless steel (9 pitch prop), so I know the hub is good. When I replaced the prop the slipping was not any better, maybe even worse. So, that kind of makes me think that something in the foot is slipping. When the engine slips and revs up, it does not make any unusual noise or anything, just slows in pulling and revs up, I can back off the throttle, let it catch , then ease into it, and It will go into plane fine. ANY help with this would be appreciated, THANKS

 

[TOHATSU GURU]

Re: 03 nissan 18 hp 2 stroke spinning out or clutch slipping?

It would be almost impossible for anything to be wrong with your lower unit. You are probably too high in pitch with a ten, not too low and should have started out with an 8 or 9 pitch. But, the most likely problem is that the engine is mounted incorrectly on the transom. With the engine on the transom your cavitation plate should be level with the bottom of the boat. Try it there and play with the trim angle in various positions. When you get to one that works you can then try raising the engine on the transom a 1/2 at a time and playing with the trim angle again. At some point you will have the problem that you have now...Then go back to the previous setting where everything worked best.

Propping and trim are all trial & error.

 

[willys_truck]

Re: 03 nissan 18 hp 2 stroke spinning out or clutch slipping?

thanks for the reply. The engine is a short shaft and the boat is set up for a short shaft engine. I will play with the trim setting and raise the engine up if the trim setting does not take care of it. Thanks again

 

[willys_truck]

Re: 03 nissan 18 hp 2 stroke spinning out or clutch slipping?

i took the boat to the water today to try adjusting the trim, I went by myself, (the boat always spins out more when there is one person up front and one person driving). I moved the trim through all the settings and I ended up having to go back to the original setting for the best performance. I did notice that the plate right above the prop, is 2 3/4" below the flat bottom of the boat. The is just a clamp on motor, so there is not really a way to move the engine up, is there? THANKS AGAIN

 

[TOHATSU GURU]

Re: 03 nissan 18 hp 2 stroke spinning out or clutch slipping?

Just add a piece of wood on top of the transom.

 

[John_S]

Re: 03 nissan 18 hp 2 stroke spinning out or clutch slipping?

I'd mark your hub and prop and make sure it is not the hub. I've had two of the stock nissan props hubs spin on my 18. While you need to raise that motor, with it being below the bottom, its not causing the symptom you describe.

 

[willys_truck]

Re: 03 nissan 18 hp 2 stroke spinning out or clutch slipping?

I bought the engine used. I do not know if it makes any difference, but the prop that came on the the engine when I bought it was a 10 pitch aluminum solas prop. The new prop that I just put on the engine is a 9 pitch stainless solas prop.