Need help on how to fix engine mounts

[FReyes]

After searching all summer for a boat I finally found one that seemed to be perfect. I'm in contract on a 1985 Trojan Intl 10 meter for $11,500. Spent the weekend on the boat going over all the systems. My only concern are the bolts on the engine mounts. I found a few of them were not grabbing to the stringer. I'm able to pull a couple of them midway out with my hand. I'm figuring the stringer must be rotted in these areas. Funny thing is on some of these the bolt right next to it tightens just fine. Damage is on both sides. The engines are Crusader 350 hp with 385 hrs. If I don't accept the boat it will cost me $1200. The boat appeared to be extremely solid. During sea trial everything seemed fine. The engines showed no flexing or vibration. Any idea of the cost to fix this? Is there something I can inject into the bolt holes to repair? I'm thinking of buying a moisture meter to try to determine the extent of the damage. I need help to decide whether to let it go or repair

[bjanakos]

It's difficult to tell without more data... A moisture meter, a knock test, and a qualified surveyor should be the next step (or the first).

It could be that the stringers are totally gone or that the bolt was simply over torqued and stripped. In either scenario, loose motor mounts are not good and not cheap to fix.

[todd brinkerhoff]

It's difficult to tell without more data... A moisture meter, a knock test, and a qualified surveyor should be the next step (or the first).

It could be that the stringers are totally gone or that the bolt was simply over torqued and stripped. In either scenario, loose motor mounts are not good and not cheap to fix.

X2

Remember, unlike a vehicle, the entire weight and force runs through the motor mounts.

[FReyes]

If there is no rot, I am thinking of pouring some epoxy with milled fibers and glueing in a stud bolt and use a nut on top. Anyone ever tried that?

[FReyes]

I found out that these Trojans have all glass stringers except where the engine is. There they have a wood core the lag mounts into. What I'm doing depending on the amount of rot is either inject reinforced epoxy or over drill the whole and insert a wood dowel. Feel comfortable closing now. Thanks everyone for the assistance.