is there another name for it? I don't see many references to it -- is it similiar to the velvet drive?

what kinda HP can this tranny take???


thanks

Mark

They were caled the MercTrans. I`ve have several over the years, the weak link is the pump gear. If you hammer it hard the gear will split in half and loose pressure

My guess is about 450 hp max, maybe more if you are easy on them. They seem to last longer if you prop down a tad and spin the motors a little higher. These trannys don`t like to be strained.

Good luck,

Kurt.

Good answer!

Good answer!

MercTrans II. -- Operates like B/W Velvet Drive but weighs less than half, is about 6" shorter and far more delicate. Previous answer is totally accurate but pump parts can be upgraded by "cryo-treating". --- Jer

THis is an old thread, but I really need to ask Biggus and JPClear about recommendations on fixing a shot MerTransII or going to something else - parts are nearly non-existant, and I'd like to look at something "less delicate". I've had my 74 SRV300 for 10 years, and honestly - 90% of my mechanical issues have been tranny related. What's cryo-treating? I believe the pump failed this past weekend on my port engine and am evaluating my alternatives before jumping in....

If you have the room in front of the engine (about 6 or 7 inches) then go with the BW tranny. It will take a LOT more HP then the Merc Trans.

Jon

OK, here is what I have done just recently. I located a B/W late style 71-C for TRS(the shorter, lighter B/W) with all the goodies needed to upgrade. (bellhousing, cooler, lines, linkage, starter, coupler, etc. for less than a grand) I am sending the tranny to Tom Huber who will build it to take 900+ hp. Will install it this winter or when the MerCtrans fails; whichever comes first. This requires the space to move the engine about 5" forward but the results are a much stronger installation and a bulletproof, nice shifting drive. --- Jer

Of course, there is the question of what I'm going to do with my MerCtrans if it survives till I make the swap. I have "tricked" it with some apparent success since it's well into it's second season behind 600+ hp with no problems. But, I DO NOT PLAY COWBOY! It would probably handle 450-500 hp forever. --- Jer

according to Galen -- at http://www.speedmasters-inc.com/ -- there are plenty of parts for the merc II

He rebuilt mine last year (at the recommendation of Jo Nunez) -- turns out there are different models of the merc II tranny -- factory rating on the later models is 450hp -- without modifications.

I'm running 500hp through mine -- and while i don't hammer the stick for take off -- i other wise don't worry about my tranny. I've not had any trouble with it at all.