Merc Trans What do you think?
 

Any one using these still? Are they worth having rebuilt? Will they hold up to 450 HP Small Blocks?

Back in the old days when Mercury and Ford were in bed together the MercTrans was born. Most of the guts are from the C-6 Ford hydraulic automatic transmission. It was better than the Borg Warner in three aspects:

1. It was lighter with its aluminum case.
2. The engine could be closer to the transom for better weight transfer and front of the engine accessibility.
3. It robbed less horsepower from the propeller.

I don't believe it was ever offered with big horsepower.

Cozzi, as usual :ernaehrung004: is right on the money.

Years ago, I had a pair of blown smallblocks (the old Hells Banana M-666) in front of the MercTrans with zero problems. Beat the hell outta them :cool-smiley-027:

Also had one in front of a twin turbo Gale Banks 482 in my 24 Superboat. It didn't work well in that application....:D

Kurt

They should be fine for the smallblocks. I think I have seen them on the 420 TRS set up before from the factory. (not positive on that one, you gurus probably might be able to shed a little more light)

as for Bigger power, I have heard they are not as good as the borg warner ( after it was upgraded of course)

I had the one in the Donzi rebuilt, added an extra clutch, and had the shaft clearance. Should be good to well over 500 hp I was told. Mine came stock in behind a 454/330, with a Trs. Love it.

Thnaks for the info
 

We just bought the new Race boat and the guy that used to race it had them for over 20 years"boat is a 79" but a couple of people are telling me to swith to the Borg Warners. I am trying to keep this as low budget as possible so i think just a good rebuild from Bam with the extra clutch packs will do the trick?

The merc trannies are not the toughest things available. They can however give you good service. Borg warners will slow the boat. Partly because they move the motors forward.
Jim

Merc Trans
 

Can i expect them to last the whole season?

Thats a tough question. I think the biggest determining factor is the touch of the throttle guy. And it is my opinion a cleaver type prop is more forgiving.
Jim

Merc Trans
 

:DHave a great throttle man and are running 3 blade cleavers so i guess it will be a learning experience. Thanks

I have 3-blade Mirages on mine, and the Merc trannies fried on the second trip out. I have NO confidence in them.

Knuckles
 

Who did the rebuild? Did you add the extra clutch disk?>

absolutely...

Buiz
 

Ok what do you have? Rebuilt ever? HP?

I had TNT rebuild it with the pump mod's and extra clutches, it shifts and works like a dream... my engine is about 425 hp and it's a 454, we have several friends making almost, and up to 700 hp, and they have had excellent success with them, I wouldn't trade mine for anything.. I wouldn't hesitate to get it built right and use it for your application

I have them on my Formula and also my Donzi 18. The Donzi has a big block 330hp and no issues. The Formula I ran for three years with out any issues. I have run long WOT runs and it seems to be ok. Just watch the temps. I run B&M Trick shift in mine.

Thanks
 

Thanks to both of you for the info

WOW! Glad to see such positive comments on the Merc trans. Most people seem to dog them. I have them in my 33 Cig behind a set of 420HP's and (knock on wood) have not had any issues during my ownership (2 1/2 yrs). From what I hear the parts are readily available and fairly easy to rebuild. Sounds like the extra clutch pack is the way to go.

Keep the testimonials on these coming.

had them in my 28ss that i sold this summer, owned the boat for nine years not one problem. keep the fluid cool,oil changed, put a pressure gauge on them to keep an eye on them, if the pressure starts to drop repair them before u f__k them up, an last but not least throttling the motors when u are lauching it. also i have one trans complete and one disassembled for sale and parts for those transmission.

Thanks again
 

Seems like allot of people have some good things to say. I just dont want to put out 3600.00 and not have them last at least one season. Seems like heat is the number 1 enemy.

Heat, rpms, torque, heavy throttles are all enemies.

The Borg warners are more forgiving and you can build them to be stronger trannies. If you are looking for bulletproof then you have to send the borg warners to a reputable builder and have them upgraded to do more than you need them to do.

You can get reliable service out of the merc trans if you don't overload it, overheat it, overpower it etc. Fact: it can be upgraded. It depends on the overall circumstance of the boat, weight, HP, etc to determine what how you need to rig the tranny.

You should call HUber marine, Texoma marine or Bam and ask their opinion, but It sounds like you will be OK in your situation.

$3600 for what? that's abot 3 times too much..

$3600.00 would include the price of pulling both engines, separating the trannys and doing complete tranny overhauls and putting it all back together...right? If not, you're paying too much.

The Borg-Warners steal about 25 HP from the props.
The MercTrans takes 6 or 7.

$3600.00
 

That is the price Bam quoted for 2 tranies from them rebuilt with the extra clutch packs. I will be doing the work myself for the install. Not sure about doing the borg warners because of the extensive engine relocation and extra weight.

Trannies were on the boat when I bought it so I am not sure who did the rebuilds. They were rebuilt about 6 months before I bought it. I have two 502's in the boat, so with big blocks the trannies are somewhat strained and I think that they may have overheated. One had pink fluid, so I think that the cooler may have had a leak in it. Be sure to replace the coolers when you get your rebuilt.

If you want I have a pair of them that I just rebuilt that I can sell. They ran real well and I only have about 10 hours on them since rebuild. They were rebuild with brass clutches and all new seals...... I did not put in extra clutches as the brass clutches to allow for some additional power. Both pumps were perfect when we took them apart. They are still in my boat so I would have to pull my motors so I am not sure how much of a rush you are in but it could work out. I ma upgrading the the BW because I built two blower motors.

Bam quoted me $1800 per tranny, I also believe it's a FMX not a C6. I have the planatary out of an FMX and Mercury just lathed off the front and welded the clutch pack carrier to that, planatary geaars are the same, why couldn't a person drive out the pins and rebuild the merc with the Ford gears?

Audiofan
 

You have a message

The last time I rebuilt one, the parts came from right from Merc in Ford wrappers.

From what I remember the weak links in the system are the shaft , the hub that holds the clutches and the key way to the pump. I would hope all those pieces and the pump are new in your rebuild price. As far as extra clutches the plates aren't the weakness and more plates put more load on the shaft and the hub. MRD used to custom fabricate a lot of the internal pieces including the hub gear that holds the clutches. I don't know what the did to toughen up the key way to pump connection. Anyway if you rebuild it properly and use new stuff you should be OK for your small blocks.
Jim

the pump from merc was $1600 the last time they made them.

Merc Trans
 

I dont think merc makes any parts for them anymore.

Your right I just looked up some stuff. Pump was 806. but is NLA.
Shaft was 87. Now NLA. Its been a while since I've worked on one. Does Bam have a source for parts? Or are the making some parts for it? I don't know but Labor wise the aren't that involved.
Jim.

I wish my computer hadn't fried. I could show you the pictures of the clutches in my Donzi when I first bought it, that would make you cringe.:eek:

I think that I will have some ugly-looking clutches also after mine is taken apart also. Here is how it was driven while the trannies were still good.

http://www.youtube.com/watch?v=RvckKIIEuls

Knuckles
 

Nice video

Merc trans
 

There is a gentleman on the board from Kennebunkport, Maine who runs these in a 28 Cigarette. I think his name is Brian. He bought my two Merc trans take - offs as spares. Very knowlegeable, nice guy. It is probably a good idea for you to do a search and contact him.

Barry

Thanks Barry
 

Thanks

trs
 

I have a pair of BW trs trans. just listed in the swap shop.

I have these transmissions ad need a seal kit for one. does anyone what part number i'm looking for? I can not find these transmissions listed any where.