Mercury 25 hp motor removal and replacement

[seanymph85]

I have a 1985 Sea Nymph 14R aluminum V-hull boat with a 1987 Mercury 25 hp motor on it. I need to find a way to remove and replace the motor so I can work on the bunk boards. I have never done this before and need suggestions to do it safely and insure the motor is back exactly where it needs to be on the transom. I assume the motors are to be centered on the transom.

I can possibly use some type of winch arrangement which I don't have presently along with the open ceiling supports in my garage. I would be uncertain what support points to use on the motor so as to prevent any breakage from lifting the weight of the motor off of the boat. There is electrical wiring attached which with the exception of removing it from the battery towards the bow of the boat I would be uncertain of how to remove and replace properly on the motor end itself.

If anyone has suggestions how one person can remove this motor so I can better position my boat on the trailer or remove it to work on the bunk boards and likely replace the two different types of existing brackets with swivel brackets I would certainly appreciate hearing from you regarding your experience with this concern. :joyous:

 

[Bob_VT]

Re: Mercury 25 hp motor removal and replacement

That motor weighs 105 lbs. Unbolt it and left it off. When you go to re-install it.....us a tape measure and mount it equal distance from the sides of the transom. It is really easy.

 

[JimS123]

Re: Mercury 25 hp motor removal and replacement

I have the same boat and also had a 25 on her at one time. I built a stand out of 2x4's for use when it was off the boat. The motor was also bolted to the transom thru the motor's mounting holes, so relocation is a piecocake. (if yours isnt bolted it should be!)

Put the stand behind the motor, take out the bolts, loosen the clamps, pick the motor straight up and set it down on the skeg....rest. Then pick it up again and set it on the stand. I've done it that way till retirement. Now my wife moves the stand to help.....LOL.

 

[seanymph85]

Re: Mercury 25 hp motor removal and replacement

That motor weighs 105 lbs. Unbolt it and left it off. When you go to re-install it.....us a tape measure and mount it equal distance from the sides of the transom. It is really easy.

I didn't realize the motor only weighed that much. I just know it seemed that end was fairly heavy making it harder to adjust position of the boat on the trailer bunks etc with the motor on it so I assumed it was much heavier than that.

Thanks for the info!

 

[seanymph85]

Re: Mercury 25 hp motor removal and replacement

I have some left over 2x6's I could use for part of a stand if needed and can get 2x4's later on. Would you happen to have a picture of the motor stand you made? i might even be able to put a couple of small lawn mower wheels or something to make it into a stand dolly arrangement.

 

[seanymph85]

Re: Mercury 25 hp motor removal and replacement

I have the same boat and also had a 25 on her at one time. I built a stand out of 2x4's for use when it was off the boat. The motor was also bolted to the transom thru the motor's mounting holes, so relocation is a piecocake. (if yours isnt bolted it should be!)

Put the stand behind the motor, take out the bolts, loosen the clamps, pick the motor straight up and set it down on the skeg....rest. Then pick it up again and set it on the stand. I've done it that way till retirement. Now my wife moves the stand to help.....LOL.

Here are a few pix of the current mounting arrangement. Glad to check this out prior to having boat in open water!

 

[carholme]

Re: Mercury 25 hp motor removal and replacement

http://forums.iboats.com/boat-resto...ing-o-b-motor-stand-instructional-266008.html

Gerry

 

[roscoe]

Re: Mercury 25 hp motor removal and replacement

The thread in the link below has many examples of motor stands.

Some are small and simple, some are large and elaborate.

Don't miss the ones on page 2.



http://forums.iboats.com/boat-resto...ing-o-b-motor-stand-instructional-266008.html

 

[steelespike]

Re: Mercury 25 hp motor removal and replacement

If you just need a spot to store the motor.If you have an open stud wall just screw a 2 X 6 across a corner.
or pick a stud and screw a 2 X 6 to it and add a diagonal; brace down to the base of the wall.
Just getting down and dirty and not wasting any time.

 

[JimS123]

Re: Mercury 25 hp motor removal and replacement

I have some left over 2x6's I could use for part of a stand if needed and can get 2x4's later on. Would you happen to have a picture of the motor stand you made? i might even be able to put a couple of small lawn mower wheels or something to make it into a stand dolly arrangement.

Two and a half 2x4's. 2x6's would work too. That's a 25 Yami on it.

 

[seanymph85]

Re: Mercury 25 hp motor removal and replacement

Thanks for the quick route idea. I do have an open stud wall. While I want to make one of the other stands with casters in one of the prior posts this will help until I can get better equipment to cut the angles on the 2 x 4's. I am guessing a radial arm saw may have been used or a table saw with accurate sliding/guide. In any case this will get the motor off and on support until I can get or borrow a better means to cut the angles. I have a small older table saw and for angles I don't trust the accuracy across the width of the 2x4's.

 

[Bob_VT]

Re: Mercury 25 hp motor removal and replacement

Be forewarned........ The motor has an awkward balance when it is in your hands............ top heavy.

 

[JimS123]

Re: Mercury 25 hp motor removal and replacement

Thanks for the quick route idea. I do have an open stud wall. While I want to make one of the other stands with casters in one of the prior posts this will help until I can get better equipment to cut the angles on the 2 x 4's. I am guessing a radial arm saw may have been used or a table saw with accurate sliding/guide. In any case this will get the motor off and on support until I can get or borrow a better means to cut the angles. I have a small older table saw and for angles I don't trust the accuracy across the width of the 2x4's.

I use a table saw for furniture making. For lesser things its too much trouble to get it out and then clean up the mess in the workshop. The stand in the pic above was cut in the driveway with a portable battery operated reciprocating saw. In the past before I bought the saw I often used an old fashioned hand saw. There are only a few cuts to make, 2x4's are soft and the only angle cuts are for the braces, which don't have to be fancy.

I have 30 or more motors hanging on the walls, and at least a dozen stands, all of which were rough cut and nailed together.

 

[seanymph85]

Re: Mercury 25 hp motor removal and replacement

Be forewarned........ The motor has an awkward balance when it is in your hands............ top heavy.

Thanks for the reminder. I was thinking that might be the case and was considering having an extra person help in case it was needed to help balance in the event the motor was top heavy. Which clearly it is. I know the metal can probably crack and break easy so we'll be careful in that regard. Given the motor is only clamped and with locks and not bolted I am considering drilling out the bolt holes from the motor mount on the outside to inside of the transom prior to taking the motor off but not having done that before am very cautious about potential repercussions. A. given the top of the cross brace is real close to where the center of the hole would be and B given the need to somehow seal those holes around the bolt etc. to prevent internal rotting of transom. I would assume a metal bit the right size would be in order.

 

[seanymph85]

Re: Mercury 25 hp motor removal and replacement

http://forums.iboats.com/boat-resto...ing-o-b-motor-stand-instructional-266008.html

Gerry

I downloaded the PDF of the plans for future reference. Will try to make that when I get the materials picked up.

 

[JimS123]

Re: Mercury 25 hp motor removal and replacement

Thanks for the reminder. I was thinking that might be the case and was considering having an extra person help in case it was needed to help balance in the event the motor was top heavy. Which clearly it is. I know the metal can probably crack and break easy so we'll be careful in that regard. Given the motor is only clamped and with locks and not bolted I am considering drilling out the bolt holes from the motor mount on the outside to inside of the transom prior to taking the motor off but not having done that before am very cautious about potential repercussions. A. given the top of the cross brace is real close to where the center of the hole would be and B given the need to somehow seal those holes around the bolt etc. to prevent internal rotting of transom. I would assume a metal bit the right size would be in order.

"Internal" rotting really isn't an issue. The 14R merely has a piece or ordinary marine plywood bolted to the aluminum with carbon steel screws. I drilled for engine bolts, drilled to route a depthfinder cable and drilled for snaps for the cover. My original piece of wood lasted 43 years an d I never sealed any of the holes because they were above the waterline. I replaced it in 2007 because it looked a little ratty. It was so small I got a piece of scrap plywood and painted it. I expect the new piece will outlast me.....LOL.

 

[seanymph85]

Re: Mercury 25 hp motor removal and replacement

"Internal" rotting really isn't an issue. The 14R merely has a piece or ordinary marine plywood bolted to the aluminum with carbon steel screws. I drilled for engine bolts, drilled to route a depthfinder cable and drilled for snaps for the cover. My original piece of wood lasted 43 years an d I never sealed any of the holes because they were above the waterline. I replaced it in 2007 because it looked a little ratty. It was so small I got a piece of scrap plywood and painted it. I expect the new piece will outlast me.....LOL.

Okay thanks! I guess I was just being over cautious because years ago I had an old Tri-Hull FG bass boat with a 75 hp outboard and nearly lost the motor to the bottom of the lake because the transom cracked at one point. The motor was just barely hanging on and when with a tow we finally got the whole rig back to the boat launch and on the trailer we had to strap up the motor with a "winch" type strap to be able to move the whole thing safely. It was repairable fortunately but didn't want to see that happen again due to any neglect. It was a hidden problem as I hadn't seen any obvious warning signs previous to the incident.