motor mount bolts loose.... options?

[moparron]

So.. I pulled my motor to replace with a new one (that doesn't spray oil all over). I went to clean the crude out of the bilge the other day... BTW scrubbing bubbles works wonders! While cleaning the bilge, i found out that my port motor mount bolts were just flopping around in the holes.
So.. what are my options here?? As you can see from the picture the mounts are on "boxes". I have a few ideas - but not sure if I'm over thinking or under thinking this??
1) Cut the box open, install a piece of 4X4, and glass the box back together
2) inject a mixture of resin and sawdust into the holes (that will be a lot of sawdust)
3) Capture a Unicorn and chain to the boat until things fix themselves

 

[jbcurt00]

On the new to you this past winter 1989 Sebring?

They are part of what anchors the motor in place and maintains the outdrive alignment on a 25+yr old boat.

IMO, you need to do a very thorough inspection and core the below deck stringers, motor mounts and transom.

Repairing/replacing the motor mounts w out inspecting the rest may leave further potential problems that should be addressed now while its the off season and you've already got the motor out.

 

[omc_parted]

My two cents: I had to replace/rebuild all my mounts, the old ones had 2x4s in the same kind of epoxy/resin "boxes". Not sure how long it would take for fiberglass to soak into a thick piece of wood, but I made my new ones out of PL'd, resined 3/4 inch "sandwiches". I want my repair to be so waterproof that I NEVER see the same mess that I had found during my rebuild. Better to over achieve than to repeat. Takes a little longer but if you want the full power of the engine to transfer to the prop, you need a solid motor mount configuration

 

[Second Chance 248]

It has to be a fluorescent pink unicorn or it won't work, also forget the chain idea, you should use 1700 and epoxy tab it's legs to the trailer
As mentioned above, a complete inspection is in order while you have that motor out. For mounts like those, you might want to consider a composite to avoid ever having to do again, just my 2 cents

 

[moparron]

Yes on the new to me 1989 Regal Sebring. Which has so far been a major learning experience.
The problem with living on the Space Coast.. is we our "off season" is only three weeks in January. Granted - since I got the boat in January I've only had her on the water three times. Once in January, once in February and once in August. So it's all off season to me anymore.

On doing the through inspection - I am assuming that you mean.. .cut all the floors out and start cutting holes in the stringers? Granted - I really hate that dark red carpet in the boat, but I wasn't ready to tear it all out YET Transom 'seems' solid... with all the bolts I removed when I took the full width swim platform off... but I know, it could be deceiving.

So the general consensus is to cut the boxes open and redo them? At this point, if I'm gonna do one I might as well do both - eh?

 

[moparron]

Oh... Florescent pink!! All I could find were florescent green ones.. that figures

I wonder if I brought the boat back to Regal, if they would take pity on me and rebuild/Restore the whole thing? BWAHAHAHAHAHA

 

[jbcurt00]

A seemingly solid transom often isnt. Look thru other resto topics, soft motor mounts often leads to soft stringers.

In the 1 pix you posted, I can see 2 stringers that are against the motor mounts. Take core samples there.

W the motor out you have nearly full access to the transom at the keyhole. Core around it, and inspect every transom thru hole by removing the thru bolts and inspecting the transom core.

Depending on the core results in those areas will dictate what further action is necessary, if any.

Water got into the motor mounts, so truthfully, good results in those easy to access areas isnt a guarantee there isnt a problem in other hard to reach areas. Slightly less likely, but not a guarantee.

Core holes can be filled w 3M 4200/5200, or resin filler (polyester or epoxy). As they are drilled from the interior, no cosmetic damage or increased likelihood of causing additional damage.

A 1/4in drill bit, marked for 1.25in depth can be used for coring. Wet, damp or dark shavings isnt what you want. Dry light shavings is a good sign.

Taken high, low and side to side in multiple locations.

Good luck.

Take lots of measuremnts and dimensions to try and rebuild the mounts as close to what you remove.

You need to remove the mounts fiberglass and all, and grind down to clean glass on both mounts. Then use multiple layers of exterior plywood wrapped w CSM and poly resin stacked and wrapped again w CSM and resin laid up into the mount location w 1708.

Removing the tops and refilling the void, after removing the rotten wood, wouldnt be how I'd suggest or fix it. Wouldn't use a 4X4 or dimensional lumber of any kind, esp not pressure treated. Kiln dried PT plywood would be fine, if you can find it, but thats not available here, even by special order. The space coast may make it more readily available.

 

[moparron]

Wow... Jb, seems you have done this a time or twenty!
I got everything you said until you got to CSM. Can you elaborate on what CSM is? I haven't played with glass in twenty years or so. And then it was automotive. Thirty years since I did any on a boat (A dinghy for my mother's wooden sailboat)

 

[Scott Danforth]

I would use laminated plywood glued together with either PB or tite-bond III.

CSM = Chopped Strand Mat

 

[moparron]

Oh.. that makes sense for CSM!!!
With all this talk of rotting stringers and transoms - on top of at least one motor mount box. What about Composites? Like Coosa board? Or is that not cost effective (I haven't even looked at pricing yet)

 

[Scott Danforth]

What about Composites? Like Coosa board? Or is that not cost effective (I haven't even looked at pricing yet)

not cost effective, and not as strong.

I used arauco plywood from Menards for my rebuild. more plys than most, and exterior grade glue. I then hollowed out a pocket in my mount blocks so I could thru-bolt the front motor mounts vs using lag bolts. The blocks were covered in 2 layers of CSM then tabbed into the new stringers with a couple layers of 1708, then covered with a few more layers of CSM.

I had even gone to the point of making a tapped nut plate for the bolts. however my drilled holes were off just a bit and my layers of glass a bit thicker than I intended, I ended up with large fender washers and a tube of 4200 covering the tripple coated bolts when I was done.

in 40 years from now it may need attention, however boats will hover over the water (and the Cubs will win the penant race)

 

[moparron]

Okay... it was an idea anyway - throwing coosa board and other synthetics out Good ol' plywood it will be
I have been toying with the idea of through bolting, as it seems a bit more logical than lag bolts. But trying to figure out how to have that box open enough to get a wrench into and still maintain enough strength. I am probably way over-thinking this when "gusset this and gusset that" starts popping into my head. I think when the boat was build they just laminated a 2X4 intot eh box and called it good?? I haven't opened it all up yet... still in research mode.

 

[Woodonglass]

If you use plywood and lag bolts and do it correctly (not like the factory did it!!!!) it will last far longer than you will own the boat!!!!