is this a small or big block boat? more important-alpha or bravo drives. if alpha the bottom bolta are aluminum and go thru housing inside the foam seal and should be sealed. they come with a rubber gasket thingy, but i would add sealer. for zz28, the bravo lower bolts are threaded into the housing and don't go thru.

These are 454's/bravos from 1990. The bottom alum bolts have nuts (also alum) on the inside after they go thru the inner transom plate. The bolt heads have a square shape under their round head that engages the square hole in the gimble housing.

Another member mentioned the new bolts come with a rubber washer/gasket and that a SMALL amount of sealant should be applied to the rubber gasket.

When the drives were removed, I had to dig a little black rubber (or maybe sealant) from the bottom holes in the transom.

These bolts appear to be exclusive to the early drives (ser# 0B664190 THRU 0F729999 )

I have the same year setup. I replaced all those bolts last year when I had mine off. I'm almost sure you are right that there is a rubber washer/o ring that goes on that bolt. I remember thinking the same thing that they are not inside the sealing area so they have to have something.

I can't remember if they came in the bolt kit ($20 / bolt w/ anode cap) or I had to buy separate. I think it was separate because I had to go back to the shop to find it. I'll look on my boat /pictures today and see if it jogs my memory. I know I did add sealant on that bolt too....I think 4000 or 4200.

Dean

The lower bolt that has a small stud on the head for the anode to screw on is yet another version during that time period. Mine has no provision for an anode.

I just got off the phone and the rep said the rubber washer does not come with the bolt, so I had to order it separately.

the answer to your ? yes you put 4200 on then but only on the inside so then or fi you get allot of water up to the bolts the water dont seep past the bolts and sep into the wood..ever see how allot of guys on here ask if they ever seen the bottom bolts or studs rot off,,this is why you seal them.a circle on the outside and a circle on the inside and then the threads ..

Sounds like a good plan FIXX. Hoping I never get enough water in the bilge to reach the lower bolts but sh!t does happen!

Correction: Installed the gimble housings last weekend. The 2 lower (alum) bolts are within the perimeter of the foam seal. They use rubber washers to seal the bolt heads. If the rubber washers leak, water enters the "dry" area.

I used the correct rubber washers and a bead of 4200 to make sure they seal.

Before installing the inner transom plate, I used 4200 around the lower bolts in case the bilge takes on a significant amount of water like FIXX suggested.