Force mounting

[TMALEGA]

Hello all i am hoping i can get a quick response here. I am transplanting my 1985 85 hp force motor from one boat to the next. My question is what size bolts i should use to go through the bottom of the mounting bracket. The top has those washer and wing screws on the inside of the splash well. The holes in the new boat are in the same place as the motor needs. But they are smaller. So i didnt know if i was suppose to be using a smaller bolt. I was thinking this since they used a block on the inside to support the transom and used much bigger bolts. Is there a size that works better then others.?

 

[lucas_chrysler_1]

Re: Force mounting

the bottom bolts dont have to be as big as the top(you dont have to worry you got the clamps) because the bottom bolts dont have much stress on them (only in sharp turns) with the top bolts you have huge amount of force being pulled on them, but the bottom is just sheer factor. 3/8 grade 5 stainles bolts will work great. or what ever size holes are in the transom

 

[Frank Acampora]

Re: Force mounting

3/8 X 3 1/2 or 4 inch long STAINLESS depending upon transom thickness. Use extra thick stainless fender washers on the inside and use Nylock nuts. Smear the bolts well with silicone RTV and squirt a good bit into the holes too. Too much is just enough to ensure that water does not infiltrate the transom at the holes.

The bolts should be held from turning while a second person inside the boat tightens the nuts. Tighten firmly and securely, but they don't need to be so tight that the washers bend and sink into the inside of the transom.