Moving motor up or down-use sealant?

[Proselect]

This is probably in the wrong forum but there are a lot of people who do this a lot in this forum and would know. When I move my motor up two notches on my transom do I use some sort of sealer behind it? I see there is a silicone or somthing oozing out the edges now. What do I use if it needs it?

 

[steelespike]

Re: Moving motor up or down-use sealant?

I've never had to move one up.But as I understand it it is a mechanical procedure
on the mounting bracket proper not directly involving the transom.unless there is a hole in the transom I don't see a need for a sealer.If there is a need to seal the mechanical parts from corrosion some sort of marine silicone.I'm sure someone more experienced will stop to help us out.

 

[Triton II]

Re: Moving motor up or down-use sealant?

This is probably in the wrong forum but there are a lot of people who do this a lot in this forum and would know. When I move my motor up two notches on my transom do I use some sort of sealer behind it? I see there is a silicone or somthing oozing out the edges now. What do I use if it needs it?

3M 5200 does a good job. If there's an unknown sealant already there, it may be an idea to remove the motor with the bracket attached (generally there'll be some hoisting lugs under the cowl) having noted the current hole position. Then remove the existing old sealant and apply the 5200 generously especially around the bolt hole areas. Replace the motor in the new position and bolt her up... not too tightly and clean up any overflowing 5200. Let the 5200 start to cure and then torque the bolts to about 50 ft lbs. Wipe off the excess 5200 to neaten things up around the bracket. Install the locking nuts using thread lock and allow the 5200 to cure completely. Be aware that two holes higher is a big amount and you may have to trim the motor down far more than you're used to, in order to prevent ventilation. Good luck.

 

[Proselect]

Re: Moving motor up or down-use sealant?

thanks triton. I know moving it up two holes is a lot but the motor is as far down as it goes now my av plate is under water at wot. I have another thread on here dealing with that, I was just curious about sealing the motor to the transom. What really stinks is I just repainted the boat and taped around the motor. Now after I monkey around getting the motor height right and proping it correctly then I will have to clean up around the motor and repaint and try to blend it all in.

 

[Outsider]

Re: Moving motor up or down-use sealant?

5200 is a great adhesive, but you aren't doing that. I'd use something like 400UV which is more sealant and not as tenacious as an adhesive. You might want to repower or move the engine in the future ...

 

[Triton II]

Re: Moving motor up or down-use sealant?

5200 is a great adhesive, but you aren't doing that. I'd use something like 400UV which is more sealant and not as tenacious as an adhesive. You might want to repower or move the engine in the future ...

I beg to offer the following from the Jamestown Distributor website - 5200 makes a great sealer as well as being an adhesive:

3M 5200 Marine Adhesive Sealant
Use 3M 5200 on wood, fiberglass, hardware, motors, on fiberglass transoms, seams, joints, between struts, and planking stern joints. It is extremely permanent.

Check the bonding and sealing jobs 3M 5200 can handle for you: fiberglass deck to fiberglass hull, wood to fiberglass, portholes and deck fittings, motors on fiberglass transoms, under moldings, hull seams above and below water line, Center board trunk joints, between struts and planking, Stern joints, Deck housings, etc.

3M 5200 may be easily applied with a manual caulking gun. It will remain workable with trowel or spatula up to four hours after application, and won't sag or flow in vertical or horizontal seams.

This high performance polyurethane adhesive sealant becomes tack-free in 24-48 hours, and completely cures in 5-7 days with no shrinking. The seal is extremely strong, retaining its strength above or below the waterline. 5200 stays flexible and allows for structural movement. Stress caused by shock, vibration, swelling or shrinking is effectively absorbed.

OK, Proselect - there are plenty of products to choose from: Sikaflex 291, 3M 4000UV (we don't get a 400UV in Australia) which is what I think Outsider means, 3M 4200 and the fast cure types as well.

Your choice and good luck.