K&B 7.5 outboard leaks fuel

[CamcorderRacer]

The outboard is on a Prather Lapcat II. It was running full throttle going fast and I was in the middle of trying to tune the motor by adjusting the high speed needle. The prop shaft broke I replaced it but had to take the motor off the lower half. It never run good after that. It won't reach hign rpm and runs off the glow plug. Fuel comes out of the joint between the pto housing and lower half. I dissasembled the motor and the pto bearings were rough. I inspected the inside of the motor housing for cracks. The only place for fuel to flow through is through the bearings. Ive heard that bearings help seal the combustin chamber. The front and rear bearings are smooth. I've replaced pto bearings before with a toaster ovn but don't like to until necessary. Also this motor doesn't have an oiling hole for the pto bearing like my other motor. I just like to play around with old style equipment.

 

[Grimracer]

Make sure you use a new gasket between the case and PTO. It sounds like your motor has an air leak.

Grim

 

[CamcorderRacer]

Thanks for the reply as I am thinking through this problem. There is no sel between the lower half and the pto base. All I had done was pull the engine off the lower half to remove the broken tip of the flex shaft. Then after that I coudn't keep it running wthout the glow plug attached. I have another motor that works but I like to learn how to make it run (fast). I had an air leak in the low speed idle needle that needed an o-ring and had one of the case screws come loose in another engine in the past, so this is a new experience.