Power trim on a 15 v botton

[KG4]

Just read a couple of posts about the little 15 allisons.It sounds like alot of the guys dont run trim.I am setting up a 15 ft v bottom what do you guys recomend trim or no trim. thanks

[Raceman]

When I bought my first 15 Allison in '74 it had a 1500 short shaft with no trim. It had been an APBA legal boat and the trim wasn't legal at that time. I later put trim on and preferred it that way. It is a little inconvenient to adjust manually for different water conditions and the tilt pin doesn't give fine enough adjustment with just the holes. My boat in race trim had a block on the transom that the motor rode against and it had very fine trim adjustment. Another reason the trim is nice in the case of an old inline Merc is the fact that when the engine is shifted into foward the tilt lock is unlocked mechanically. Suddenly jumping off the throttle at speed will let the engine kick out. In the case of the manual adjuster, we strapped the engine down so it couldnt move. Merc also made a set of manual adjusters for the raceboats that had a bracket on the transom connecting to the lower shock mounts. There've been a couple of them on E bay in the past year. I'd power trim it.

[DaveR]

I made a little manual block that allowed finer adjustments on a mark 55H that worked pretty well. Basically it was a block of brass that went across the J-brackets where the pin stopped the midsection. Seems to me it was about 1" square with a through hole drilled off-center that the pin went through. To adjust the trim all you had to do was rotate the block. The off-set hole changed the trim in small increments. That was a long time ago, but I don't remember having any trouble with it. Now you just can't beat power trim if you have a few bucks.