Carla

Hello !
I´m new to this forum. I live in Sweden and recently I bought a Sea Ray 255 Sedan Bridge -81 from US. Unfortunately the transmission was not a Borg & Warner but a Merc Trans II with an electrical motor to shift the gear. The drive is a TR. When I put the boat in water everything worked fine. But the third ride with the boat the transmission started to skid. When that happend we had 1200 rpm. We were lucky that could go back to the port. I checked the oil level and filled up a little to the mark on the stick. Tested the boat when she was tied, I shifted the gear into forward and back position many times and it seemed to work fine. Next ride the proplem occured again. Now the boat is up from he water and when I run it an land nothing happens in the forward position. The reverse gaear always work.
The electrical shift motor works. I have moved the shift forward and back many times and it seems to work. The shift mechanism turns in different ways from the neutral position. The oil level is ok. Have you any idea what the problem is on my Merc Trans II ? Is there anything I can check with the stuff inside the boat ? Is there any spring controlled valve inside the shift mechanism that could be faulty ?

Hope someone has any idea what to do or to check.

Best regards
Jorgen

picklenjim

Unfortunately it sound like the trans is going to have to be removed and repaired. If the electric shift on the trans is moving as you said then there is a problem in the trans. It's not getting pressure to the forward clutch pack to apply it or the clutch pack it self is worn beyond tolerance. Reverse has nothing to do with these parts so it still works. All the shifter does is direct the fluid flow to apply the forward clutchs or to the reverse band. Pressure must be good beings the reverse still works.These transmissions use some parts including clutchs from a ford FMX transmission. You may be able to get a local transmission shop to repair it for you as they are a very simple transmission. Another option would be to find another one in good working order. Usually you can find a good working used one for $6-700. Be sure to specify if you have a Ford or Chevy engine as the bolt pattern is different. Same parts internally.There's one on ebay now.
http://www.ebay.com/itm/MERCURY-MERC...s_Gear&vxp=mtr
Or you can get a rebuilt one or parts from here,
http://www.kcmarinetr.com/Default.aspx
I think I would try a local trans shop though first. You could get a gasket,seal and o-ring kit from KC Marine and a trans shop could probably get the other parts you need.

Carla

Thank you very much for reply. I was hoping there was something to check with the tranny and engine inside the boat but now I understand the engine needs to come out from the boat. The seller on ebay wants to ship in US only but I could ask him if he could ship to Sweden as well. I also see one tranny on an internal sight here in Sweden http://www.blocket.se/stockholm/Merc....htm?ca=14&w=3. Around $1200.
I should talk to them I guess.

John the Drive Man

I've done many of the Merc Trans. The problem is inside. Give me a call. 954 237 0332 I can give you a quote,

Carla

John ! I live in Sweden and my tranny is also here. The shipping cost to US and back to Sweden would be very high I think.

// Carla

Carla

Holy s..t ! Finally I bought a tranny here in Sweden, 3 hours away with my car. The tranny was originally installed on a 5,7 l Mercruiser and I have 7,4. The company who sold it told me that it will fit both 5,7 and 7,4. It looked exactly the same. The new one doesn´t fit to my motor. The inside diameter is smaller on the new one and there is also a little thing that limits the inside diameter so it doesn´t fit over the flywheel. My tranny is a MCM-E and the new one is marked MCM-B. How many different trannys are there ? Not everyone has the label still left so it´s not easy to know if the next one will fit. Is it the same parts inside ? Is it possible to strip the new tranny and put that parts in my old ? // Carla

sparky24

If i were you i would ship the thing over to the US and have it rebuilt. BAM marine, KC, or nopper marine all seem to be big names.

picklenjim

There are 2 different cases. One bolts up to Ford engines and the other bolts to Chevy engines. Is that your problem, the trans doesn't bolt up right to the engine? Chevy ones will bolt up to any Chevy engine. Not sure what all Fords the Ford ones will bolt up to. Yes the parts are the same inside and can be swapped to your original case. I just swapped the guts out of 2 Chevy cases into 2 Ford cases for a friends houseboat. Disreguard the letters on the tag as that just indicates there was some sort of internal design change. Cases are still the same either Chevy or Ford. Mercury quit using Ford engines in the mid '70's so with the one you just got being a "B" it's older than your "E" so it may be a Ford case. If the transmission bellhousing and bolt holes don't match the back of your chevy engine than it must be a ford case.

If you need information on the Merctrans it has complete rebuild instruction in the Mercury Service Manual #2.

Also reread my post #2 above. If it were me I would take both of them to a local trans shop, have them disassemble both and put all the best parts between the two in to your original case. Remember they use some parts from a Ford car FMX transmission.

Carla

Thank you very much for your reply picklenjim. It seems to me that you know what you are taking about.
I try to put a link on my two trannies and maybe you could see if the new one is from a Ford. The bolt pattern seems the same.


// Carla

Carla

The link again:

http://tinypic.com/r/2la3eax/5

//Carla