Engine stringers

[terry_thatcher]

I have never drilled or cut into the fore/aft engine stringers. Will probably have to for new engine placement. What is inside the fiberglass covering? Wood? Some glass/resin mishmash? Something else like, god forbid, foam? Thanks.

 

[bharney]

on my 1970 cm38 it's wood covered with heavy glass, still solid after 50 years

 

[jimcleary]

Terry

I have drilled into and cut off the fronts of Dana's stringers. Inside appear to be common pine 2x6 lumber. The first time the engine was moved into the main cabin for maintaince, the wood was punky (soft) where the lag bolts were. I drilled out the 8 locations and inserted 1" dowels made of oak. This fix seems to be working as the lag bolts and still tight years later. The forward ends of the stringers were also cut on 45 degree angles and glassed over the give better access around the lower part of the engine.
The first photo shows the angle cut and the second photo shows the 1" oak dowel being epoxyed into place.

Jim

 

[jose santin]

When I re-powered, then new engine was narrower that the old I had to place two steel angle beams by bolting them to the inside of the stringers. All the holes drilled produced dry wood. I also had to re-cut the top of the stringers due to using a transmission with a downward angle on the output flange ( this allows the engine to sit level) As mentioned previously, the wood core was regular lumber but all was dry.