Engine Mount/Stringer Repair -- Has anyone tried ____?

[bds85466]

I was wondering if anyone in this forum has used Seacast or Rot Doctor CPES/L&L for repairing engine mount areas?

Did it work well, poorly? What kind of shape was your stringer in?

Depending upon the extent of the rot, I'm trying to decide whether to cut the fiberglass top off and replace the guts, or use one of these sealing/filling methods. The boat isn't worth a whole heckuva lot, so pulling the floor/replacing the entire stringer seems like overkill at this point.

Otherwise, any other ideas? I'd love to hear what the all knowing forum things. Thanks!

 

[Robj]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

These types of questions get asked quite often. People looking for an easy way out for stringer repairs. Regardless of how much you think your boat is worth, safety should be your ultimate concern. Really IMO, the only way to do such a repair involves removing all the rotten wood and replacing it with new. I have tried that git rot, and found it was expensive junk that did not really penetrate much deeper than poly resin. You will find Seacast to be very pricey. Just replace the wood with new, glass it in, and it will be good as new.

Have a great day

Rob.

 

[bds85466]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

Rob,

Thanks for the response. I'm not a glasser so I don't know what kind of time/$ that's going to be. Any ideas on how big a job that is?

Maybe a better question is:

If only part of the stringer is bad, specifically very local to the engine mount holes, do you have to replace the whole thing? Can one section of rot + some good on each end be removed and replaced? Then glassed back over?

 

[Woodonglass]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

Hey bds,

I think we have a terminology issue here. You are using the term stringer but it sounds like you are talking about your transom. Stringers are the pieces of wood structure that run longitudinally between the hull and the deck and the Transom is the entire back portion of the boat that the motor attaches to. It sounds to me like you are talking about your transom. If that is the case then replacing the transom is a straight forward piece of work that could take up to 30 hours of work and about $200.00 Not much High level fiberglass skill required. Lots of posts here on iBoats to help show you and guide you through the process. You might find that once you get into it that your stringers will have some rot issues as well.

Good Luck with your project

 

[bds85466]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

Well, there might be some confusion on my part... but I am talking about the engine mounts on the inside of an I/O -- the front mounts. There may be a seperate piece, but I'm speaking of the mounts directly on top of the stringers. These dealies in the photos...

The starboard side is pretty good, but the portside has rotted ever since a exhaust mani leak...

 

[Woodonglass]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

Welcome to iBoats!
Alrighty Then!!!! Those are your Motor Mounts and yes those are mounted in conjunction with your stringers. You need to determine how extensive the rot is in the stringers. Take a drill with 1/4 inch bit and drill some exploratory holes in the stringers about 2 inches above the hull back towards the outdrive. See if you get light tan dry shavings or dark brown wet shavings. If you get wet shavings then your problem could extend back into the transom as well. If it has been wet enough to destroy the motor mound then I suspect that your problem is more extensive than you might imagine. You need to do a search for replacing motor mounts and transom for an i/o. You will find lots of threads with plenty of pics of guys that have been there and done that.


Good LucK

 

[bds85466]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

.Really IMO, the only way to do such a repair involves removing all the rotten wood and replacing it with new.Just replace the wood with new, glass it in, and it will be good as new.

Have a great day

Rob.

How should I proceed to cut out the old stuff? Take the whole mount out? Lop off the top of the fiberglass shell, pull all the rotten stuff out and refill?

 

[bds85466]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

Here's my initial plan for making my inspection/entry cut into the portside engine mount.

 

[Greg Mrozinski]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

That will work for initial inspection. You only need to cut as much as you need to determine the extent of the rot. But don't be surprised if you wind up removing most of the stringer. Remember wet wood will rot if it hasn't already started and wet wood is nearly impossible to dry out in place. So many times denial turns into reality.

 

[bds85466]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

Thanks for the confirmation Greg.

I can't quite seem to get a good answer on if it is wise to leave the fiberglass side shell or not.

If it comes down to replacing a full section of stringer/mount, how do you make the cuts?

I'm guessing that once I find the "end" of the rot, that I'll want to take another 5-6 inches or so...

Though considering what I see inside, I'm still considering digging out as much rot as I can, penetrate sealing the remaining wood, and back filling with composite...

As far as wood goes, I've seen people taking a long angluar cut from the bottom of the hull to the top of the stringer for replacement. Like a longitudinal miter joint...

Is this done with treated wood? Laminated? Sealed?

What goes between the wood and the hull again?

 

[j1hoekst]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

How did the repair work for you? I have a similar situation. Mounts are bad, stringers look fine

 

[bds85466]

Re: Engine Mount/Stringer Repair -- Has anyone tried ____?

Wow that's going all the way back to 2010. I was trying to forget about that nightmare.

In retrospect, and despite what some of the naysayers said, the fix went great.

We basically lopped the top fiberglass off both engine mounts, cored out all the rot (which was only on one side), injected/cured/sealed remaining wood with Rot Doctor CPES and then backfilled with the L&L slurry. Small layer of fiberglass cloth over the top after it had set, and it was better than new, ready to be remounted.

Ever since, the big ol V8 motor is remounted and solid. Going on 3 seasons strong since the fix and is definitely more solid and water/rotproof than real wood.

Probably not the way to replace an entire stringer obviously, but it worked for us on the motor mounts.

PM me if you want more information or the steps I took. I have lots of pictures (which reminds me I never got around to posting them here on iboats). Though I would have to check, I may even have some sawdust and L&L still laying around if you want to take it off my hands.