Stringers supporting engine

[EZC]

I have an 87' S/C with the nissan engine. One of the aluminum motor mount supports that is attached to the stringer had started to slightly pull away from the stringer. After further inspection I noticed there was some moisture in the stringer. Does anyone know if the stringers rely upon the enclosed wood for support or were they used as a form and the fiberglass is strong enough to support the engine? I would hate to go through the trouble of repairing the stringer if it is fine as is. Any advice?

[Beta Don]

My opinion is that the oak (I assume it's oak) in the engine beds is very important - The fiberglass covering it is just to hold it in place - The oak is the 'structure' of the engine bed

If I had a loose lag screw in an engine mount which could not be tightened, I would remove it, fill the hole with an epoxy mixture (West System G flex or equivalent which is excellent for use in wet locations) let it harden, drill the appropriate size hole in the epoxy for the lag screw and reinsert the lag screw. The epoxy will soak into the wood and strengthen it so that it's actually stronger than it was originally

Don

[coolchange]

I think Don has a solution ...if you have detected the rot early..but if the decay has gone deeper/further a more "robust" solution will be required...so, IMHO you first need to find out how far the rot has gone into the stringer. (previous boat had stringer rot from stern to half way to bow ..and half the transom..I learned a lot about the art of fiberglass and boat construction that summer)

[EZC]

Yea, I think I will start by making some small holes around the problem area and see what I find. I will support that mount first though. Will wait till spring to start the project. Thanks for the advice and I will post after I get started.

[tego]

EZ, I can't imagine an engine mount support in an '87 that is secured with a lag screw. All mine (also an '87 with the Nissan) are secured to the stringer with four 1/2" ss thru bolts! That Nissan has way too much torque for lag screws. Good Luck- hope the moisture is minimal. Ben

[sail149]

EZC
You might want to drill a few of those small holes low on the stringer now and let the water that is bound to be inside drain out over winter., if it is oak in the stringer it will leave a nice stain so you will know it drained.
This will allow for your favorite epoxy repair to happen in less wet environment!
The fiberglass cover should be plenty strong enough to hold the engine weight , especially in a non running mode.
Warren
Ps I do not know what wood is in the stringer but encapsulated oak wouldn't bot be my first choice as it's not rot resistant like that.

[Beta Don]

I'm not sure what wood they used for the engine beds - Frequently it is oak because they're looking for something strong which won't compress when used with mechanical fasteners. They didn't intend for the wood to get wet, so probably not a lot of thought was given to it rotting and if anything ever did get wet and rot, it would have been long after any warranty had expired

As to lag screws. The original 4D61 engine in the early boats were mounted using 8 vertical lag screws and they were monsters - 5/8ths or 3/4 diameter. My 100 HP Yanmar is also mounted with 8 vertical lag screws, but the engine mounts were drilled for 1/2 inch diameter screws. I can't imagine that 8 properly sized lag screws would not hold up with a Nissan engine - Maybe the factory didn't use lag screws, but no doubt in my mind they would have been adequate. I've seen V-8's in other boats mounted using lag screws

Don

[EZC]

Appreciate the feedback all good points. My Nissan is actually through bolted with 1/2 s/s. I will not be running the boat in gear over an idle until this issue is resolved so I might go ahead and drill some holes as suggested. Hopefully things aren't too wet.

[rnummi]

This thread should be added to the "what to look for in a used Albin 27" string. Just hopped down and looked at my mounts after reading, yep. Time for very slow epoxy.....