I was talking with Marc and K C marine was brought up. He said he had past away, said he was a really nice guy. I personally never talked to Kirk, seemed like a very good guy based on what others say about him, its a shame.

Interesting thread. Very sad news regarding Kirk.

I used to race with FMX transmissions in cars back in the day. I had a full manual valve body that I designed myself. The one thing I remember is running FEWER plates in the clutches. The shifts hit harder with fewer plates but I also bumped up the oil pump psi to about 250. It was a different application though, not saying its what you should do. The more plates in the clutch was similar to running wider tires in the snow. It would tend to distribute the load and float on top of the trans fluid where one or two plates would cut right through and lock up harder. You had to run the higher psi to do it though of course. Just a memory from reading about you guys stuffing those clutch packs. Usually more clutches were used for softer shifts and longevity in stock trannys (which may be what you want)

The teflon seals were a must. The steels were absolute trash and were why the ford transmissions sucked so bad. As soon as the fluid got hot, there went your psi through the gaps in the steels. I never cryo'd the gerator and experimented with dozens of setups running psi as high as 400-500 psi to hold those plates together under nitrous.

The FMXs suffered from weight and that huge compound planetary really tore up the mid band (2nd gear). Yes the paper plates and bands were the chit but hard to find. Occasionally I blew the ring lands off the lip of the front clutch but the later models beefed that area up (post '80).

I have a Merctrans in my SeaRay which I am rebuilding now. The challenge is going to be not modifying it ;-) I always thought Kirks ideas were great on their website, sad he's gone.

-BL

Howdy y'all from Texas. I had many great discussions with Kirk. I knew he had cancer but didn't know for sure he had died. So sad to hear. Good news is that he was a Christian and rests with the Lord now. I took some notes that I need to share somehow. I even charted out standard seal numbers that work great. The nylon seals are easily made on a lathe and I think Kirk gave me dimensions.Good thing is that Merctrans is a good and viable design to keep using. Even by this post you can see that there are tons of used parts around. The achilles heel that gets so many Merctrans is freeze damage of the cooler. The curved tip will split open and water gets in trans = bad. Rout outlet 3/8 hose to a thru hull telltale outlet and you can SEE that cooling water is passing. Keep access, via a fitting and extra hose, to the inlet water passing from belt driven pump to the trans cooler. To winterize blow compressed air thru and you'll see water clear from cooler thus removing threat of freeze damage. Should I make a Youtube video with all my info?

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Would you mind sending me that one as well, I'm in a similar situation and am about to take mine apart, it would sure help alot.

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Link to KC Marine's old website
 

Merc Trans seems to be not as bad as the reputation that precedes it.

Weakest point I have found on a MercTrans is the Output shaft, their such a small diameter. Hit your prop on something solid and it will break it. Their hard to come by also. If you see one used out there you better grab it!