Re: mike
I can't prove or disprove what wilde1j posted, but if your motor is a bad off as you say, you can definately do that to find out if the motor has internal issues then. I have a bad clutch in my boat and I can at least troll with it! It won't go any higher than fast idle with out slipping(clutch) and i can guarantee that's no where near 100 hp being applied. So, you can at least check it this way to see if things spin when they should or should not be spinning. And I don't mean to step on anyones toes.
I don't think you are stepping on toes either, but you are most likely giving incorrect information.
Unless you have a 60's vintage OMC outboard with electric shift system that was used on some of the 40hp models and V-4 models, you don't have a clutch mechanism in your motor. What I am speaking of is not the "hydro-electric" shift system and it wasn't used on other, through-the-hub exhaust outboards, either. This system was on the old pin drive models and it had a clutch mechanism with a pair of springs and a pair of clutch hubs. If you want to see what this looks like, go to
www.shop.evinrude.com and look at the gearcase parts diagram for a 1968 85hp model, with the electric shift.
As for wilde1j's comments, I don't completely agree with him, but understand what he is getting at. Trying to check for a spun hub by moving the prop by hand, isn't likely to tell you much, unless and as he said, the rubber insert is completely destroyed. At the same time, what can happen, is what you are describing - you can put the motor in gear and move forward at idle, but as soon as you apply much throttle, the hub won't hold.
This particular situation sounds more like internal gearcase problems to me. Whether it is related to the clutch dog or something else, will have to be determined. Slamming a gearcase from reverse into forward with a lot of throttle applied, could have damaged the tabs on the clutch dog and it might have done the same to the mating surfaces on the forward gear. If any of the tabs involved sheared off and is/are somewhere in the gearcase, continued use of the motor could cause further damage.
If the OP is not comfortable in diagnosing and/or repairing gearcase problems, it might be time for him to find a competent mechanic. If he goes to an OMC/BRP dealer, he can expect shop rates in the $70 - $90 an hour range, but he might also find a local mechanic who can do the work. I've run across more than a couple retired OMC mechanics, who dabble with repairs now and again. They can be just what is needed, because they know what they are doing and will usually offer very competitive rates.
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