Re-lag Bolt or Through Bolt

Weirthit

Cadet
Joined
Mar 12, 2012
Messages
12
I had just completed a successful sea trial after replacing all of the bellows and shift cables on my 1988 Welcraft 210 Classic. While standing on the teak swim step in the parking lot after pulling out, the upper lag bolt pulls out of the transom. ?DARN? I think I said as I caught my balance. This is one of four upper lag bolts. There are also four gussets that run from the stern edge of the step to about a foot below the water line (8 fasteners into the transom total).

I have not inspected the blind hole created by the lag to check the condition of the wood. The boat is in great shape and do not anticipate a dry rot problem when I do inspect.

Is the correct repair to drill through the transom and use nuts, bolts and washers to refasten the bracket or possibly fill the hole and create another blind hole?

Also, is 3M 5200 the correct sealant for this application or is there something better?

Thanks for the help.
 

DBreskin

Senior Chief Petty Officer
Joined
Oct 20, 2009
Messages
799
Re: Re-lag Bolt or Through Bolt

I have not inspected the blind hole created by the lag to check the condition of the wood. The boat is in great shape and do not anticipate a dry rot problem when I do inspect.

The bolt should not fall out spontaneously. There has to be a reason it lost grip. You may not have dry rot; you may have wet rot.
If the wood it sound you can lag it and use 5200 to seal it, but I'm guessing the wood isn't sound or the bolt wouldn't have come loose in the first place. If you do find rot be sure to check the other bolts and the rest of the transom.

Good luck!
 

Gpayne

Petty Officer 3rd Class
Joined
May 28, 2012
Messages
75
Re: Re-lag Bolt or Through Bolt

I had the same problem with my boat, except that the PO had used stainless wood screws that were definitely too small for the job. I went to my local hardware store and bought some stainless bolts, locknuts, and fender washers and thru-bolted it. I sealed the holes with 5200 and haven't had any problems since. Seems to me that in a weight-bearing application like that, thru-bolting is a better, if not safer option anyway. I'd hate to see someone have to go to the hospital after the swim platform gives way under their feet as they're entering/exiting the boat. Just don't be too shocked at the price of the bolts. If memory serves, four 1/4x3" stainless bolts, nylock nuts and fender washers cost me the better part of a $10 bill. Well worth the peice of mind, but still kinda pricey in my opinion.
 

64osby

Admiral
Joined
Jul 28, 2009
Messages
6,799
Re: Re-lag Bolt or Through Bolt

If the transom checks out a SS bolt though bolted with a fender washer would fix it so it wouldn't happen again. If you have access to it. Re due the others while your there.

5200 is the right stuff, it also has a 7 day cure time.
 

foodfisher

Captain
Joined
Feb 18, 2009
Messages
3,756
Re: Re-lag Bolt or Through Bolt

Agreed, the bolt should not have pulled out. ALERT! 5200 is permanent, no changes. 4200 will do the same job with the ability to be changed or reinspected. ps: through bolts are always a better choice given rear access.
 

Weirthit

Cadet
Joined
Mar 12, 2012
Messages
12
Re: Re-lag Bolt or Through Bolt

All lags are out now and the transom seems to check out. By check out I mean I pushed a screw driver into the wood that was exposed by the hole made by the lag bolts. It seemed to be solid.

Is there a better way of checking?
 
Joined
Oct 22, 2007
Messages
2,598
Re: Re-lag Bolt or Through Bolt

Is there a better way of checking?

If you have access to the inside of the transom you can drill several holes halfway through the transom and check the wood chips that come out. I have ovens and sensitive scales at my disposal so I've actually measured the moisture content of wood taken from a transom (and in my case it was very very wet). But even without all that equipment you can tell a lot by looking at the wood shavings.

If everything is ok then you seal up the holes with a slurry of fiberglass resin, milled fiber, and cabosil and your good to go. (For that matter I guess you could seal it with 5200).
 

SDSeville

Lieutenant
Joined
Mar 19, 2010
Messages
1,481
Re: Re-lag Bolt or Through Bolt

I must be buying the wrong 5200 because it is not that hard to remove. It is not like the permanent Locktite where you have to use heat to get it loose.
 
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