I noticed this last week that the top left (when facing forward) thru hull bolt on the motor mount had backed out about a quarter inch. I don't know if there is a backing nut glassed in place or not, but there isn't one exposed on any of the bolts that I can see and the bolt that has backed out will not tighten. I think I can wiggle my way up through the transom and get a nut/washer on the back of the bolt but I suspect it's going to be a very tight fit. I was wondering if anyone else has had this problem?
Motor mount
- Thread starter Boydaclies
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Pretty sure there's an embedded alum plate
What year is the boat and have you tried backing it out, replacing it with a ss hex bolt, lubing it up and working it back in with a lock washer? I think mine were just big ss phillips head machine screws threaded into a glassed in backing plate. A through hull bolt and nut would be more reassuring but tough to get to, for sure. Good luck, Michael
What year is the boat and have you tried backing it out, replacing it with a ss hex bolt, lubing it up and working it back in with a lock washer? I think mine were just big ss phillips head machine screws threaded into a glassed in backing plate. A through hull bolt and nut would be more reassuring but tough to get to, for sure. Good luck, Michael
2001
Michael, The boat is a 2001. The set up you describe is what we've got. It's a large SS machine screw w/ (I'm guessing) about a #3 phillip's head. If there is a plate glassed in place, then maybe the screw threads have simply been stripped down from engine vibration. Part of the problem is that the bracket that screw holds in place is 'C' shaped, making the screw itself somewhat hard to get at. I was trying to avoid pulling the motor. Boyd
Michael, The boat is a 2001. The set up you describe is what we've got. It's a large SS machine screw w/ (I'm guessing) about a #3 phillip's head. If there is a plate glassed in place, then maybe the screw threads have simply been stripped down from engine vibration. Part of the problem is that the bracket that screw holds in place is 'C' shaped, making the screw itself somewhat hard to get at. I was trying to avoid pulling the motor. Boyd
Aloha, Michael
Fix option
I had a similar problem with one of my motor mounts bolts too. Someone had gone in and put a nut on the backside as a fix but pulling on the backside of the bolt at the nut caused some chaffing. I removed everything and used "JB Weld" which is a super high-strength apoxy that filled the old hole in very nicely. In fact I built the hole back up with plenty re-enforcment inside and out and re-attached using the same bolt through the hole without a nut. The site lists the product this way: "Like metal, J-B WELD can be formed, drilled, ground, tapped, machined, filled, sanded, and painted. It stays pliable for about 30 minutes after mixing, sets in 4-6 hours, and cures fully in 15-24 hours. It's water-proof; petroleum-, chemical-, and acid-resistent; resists shock, vibration, and extreme temperature fluctuations, and withstands temperatures up to 500° F. J-B WELD is super strong, non-toxic, and safe to use. " When hardened this stuff is steel and it bonded very well to both the fiberglass and the aluminum bolt hole.
I had a similar problem with one of my motor mounts bolts too. Someone had gone in and put a nut on the backside as a fix but pulling on the backside of the bolt at the nut caused some chaffing. I removed everything and used "JB Weld" which is a super high-strength apoxy that filled the old hole in very nicely. In fact I built the hole back up with plenty re-enforcment inside and out and re-attached using the same bolt through the hole without a nut. The site lists the product this way: "Like metal, J-B WELD can be formed, drilled, ground, tapped, machined, filled, sanded, and painted. It stays pliable for about 30 minutes after mixing, sets in 4-6 hours, and cures fully in 15-24 hours. It's water-proof; petroleum-, chemical-, and acid-resistent; resists shock, vibration, and extreme temperature fluctuations, and withstands temperatures up to 500° F. J-B WELD is super strong, non-toxic, and safe to use. " When hardened this stuff is steel and it bonded very well to both the fiberglass and the aluminum bolt hole.
JB Weld...
Cheeky - Did you apply the JB Weld from the outside? I've managed to crawl up through the transom enough to get a very large washer and a backing nut on the bolts with a driver, but it was a stretch, and I'm not a big guy. It didn't seem like there was enough room to do much more than that. However, as soon as I tightened the self locking nuts, I was worried about compression on the fiberglass, even though I used the largest washers that would fit and didn't tighten the nuts down very tight. JB weld seems like a much better fix. After studying this situation I have concluded that this motor mount could have been designed much better. In addition to this bolt pulling out, there's considerable cracking in the gel coat on the outside of the motor mount pillars, due I'm sure, just to engine vibration. As these boats get a few more years on them, I bet everyone's going to have problems in this area. Let me know how you applied the JB weld. I think in the short turn I'm just going to keep an eye on my washer/nut fix, but I suspect I will have to revisit this situation shortly. Thanks for your input - Boyd ps If there's an backing plate glassed in the motor mount pillars, I couldn't see it, and the screw that came out showed no signs that it was stripped.
Cheeky - Did you apply the JB Weld from the outside? I've managed to crawl up through the transom enough to get a very large washer and a backing nut on the bolts with a driver, but it was a stretch, and I'm not a big guy. It didn't seem like there was enough room to do much more than that. However, as soon as I tightened the self locking nuts, I was worried about compression on the fiberglass, even though I used the largest washers that would fit and didn't tighten the nuts down very tight. JB weld seems like a much better fix. After studying this situation I have concluded that this motor mount could have been designed much better. In addition to this bolt pulling out, there's considerable cracking in the gel coat on the outside of the motor mount pillars, due I'm sure, just to engine vibration. As these boats get a few more years on them, I bet everyone's going to have problems in this area. Let me know how you applied the JB weld. I think in the short turn I'm just going to keep an eye on my washer/nut fix, but I suspect I will have to revisit this situation shortly. Thanks for your input - Boyd ps If there's an backing plate glassed in the motor mount pillars, I couldn't see it, and the screw that came out showed no signs that it was stripped.
Should be ok
Although I fixed the hole, I had not replaced the actual motor mount (Not stock but rebuilt by a much previous owner using laminated that had begun to de-laminate) and it snapped on our maiden voyage on the way back in this spring (very ugly, dont ask)... so I had to pull the motor mount. Everything looked excellent underneath though admittedly it had only just been applied. I made sure I put a plenty good application inside and out to the tune of maybe an 1/8 inch each side with some effort. It kind of resembled using a grommet. Try using a q-tip bent to apply inside top and around. This is what I had to do since it was the top right hole that went down. Nothing wrong with the washer and nut. Just really hard to get at the nut if it isnt a bottom hole. good luck
Although I fixed the hole, I had not replaced the actual motor mount (Not stock but rebuilt by a much previous owner using laminated that had begun to de-laminate) and it snapped on our maiden voyage on the way back in this spring (very ugly, dont ask)... so I had to pull the motor mount. Everything looked excellent underneath though admittedly it had only just been applied. I made sure I put a plenty good application inside and out to the tune of maybe an 1/8 inch each side with some effort. It kind of resembled using a grommet. Try using a q-tip bent to apply inside top and around. This is what I had to do since it was the top right hole that went down. Nothing wrong with the washer and nut. Just really hard to get at the nut if it isnt a bottom hole. good luck
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