Since I got the boat 2 years ago, the drive has been hard to install. Noticed the engine height changed about 1/8 inch when drive was removed. Finally have the time and the place to pull the engine and take a look at the rear engine mounts. Its a 2000 7.4 MPI sn L077838. Found a spring spacer missing when I pulled the engine. Parts catalog shows this serial number using the spring spacer but I see, and have read of, newer mounts without the spring. Are the new designs retrofittable to the spring type design? If so, I will order the new design kit. While engine out Im cleaning and painting the bilge, relocating the tab pumps/reservoirs, relocating my battery switch, and adding a 14inch wide swim ladder with BoBo handles to allow the arthritic wife to get in and out of the water easier. Pics show the existing transom bracket and lack of spring in LH mount.

Missing the spring

Spring in place

you have to change to the new bushings in the bellhousing to run without the spring spacer

Also, check your coupler. If you have been running like that there is a good chance its worn.

Found the rear mount bushings were at different heights. Replaced with new style bushings and repainted bilge.

Bottom of bushing well below casting.

Bottom of bushing even with casting.

New paint in bilge

You need an alignment bar. The odds of anything actually being square or level on a boat isn't so likely. So determining something is off 1/8" ....

An alignment bar will tell you the thruth...

I measured engine height with a tape measure before I removed the drive. I measured again with the drive removed. Height changed 1/8 inch. I just wanted an idea of how far off my alignment was because my input shaft and coupler had been supporting considerable weight for some time and I suspected something wrong with a rear mount. The bad mount bushing was confirmed as the problem, I expect.

and it will leave you stranded , its $500 and you have to pull the motor to replace it . Ask me how I know

I've got a new coupler ready to put on it.