Damper plate blues...and a question

bertboyer

Member III
We are still battling our transmission replacement, but we are getting closer :)

We recently ordered a Twin Disc TMC-40 transmission to replace our Hurth transmission, and we also ordered a R&D Marine damper plate from PYI that a friend recommended. Unfortunately, the new and improved damper plate with polyurethane element doesn't fit in the adaptor plate slot like the old spring plate did. See the two pictures attached below.

Do anyone know of any company that sells the spring damper plate version? We have a Universal 25XP engine. Otherwise, we are looking into having the existing adapter plate machined to fit the new R&D damper plate we bought from PYI. I'll have to say that I really like the new damper plate, and my son, who is a mechanical engineer, as well as PYI, think that modifying the adapter plate to fit the R&D damper shouldn't be a problem.

All thoughts appreciated!

Spring damper.jpegRD Damper plate.jpeg
 

Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
Found a similar engine model with a little searching, and the comments about spline wear seem real interesting.
I wonder why PYI does not simply exchange the one they sent for the correct one?

Anyhow, the video seemed worth sharing. Hopefully.

Good luck!
 

JSM

Sustaining Member
Installed the Twin Disc MG340 (TMC40) on my M25xp four years ago. The shop I purchased the trans from was fairly adamant about using the OEM Sachs / ZF damper plate (part # 3306 316 001) to avoid any problems.
The ZF plate slid easily into place and everything bolted up nicely. I found that I had to raise the heat exchanger up a bit to allow access to the trans dipstick , an easy modification.
More here
 

bertboyer

Member III
Found a similar engine model with a little searching, and the comments about spline wear seem real interesting.
I wonder why PYI does not simply exchange the one they sent for the correct one?

Anyhow, the video seemed worth sharing. Hopefully.

Good luck!
Thanks Loren. Indeed, that damper plate in the video looks like the R&D damper plate we bought from PYI. Unfortunately, they don't make or sell the size damper plate we have (the spring loaded version). The PYI rep said about 10% of the R&D damper plates they send out don't fit the adapter plate.
 

bertboyer

Member III
Installed the Twin Disc MG340 (TMC40) on my M25xp four years ago. The shop I purchased the trans from was fairly adamant about using the OEM Sachs / ZF damper plate (part # 3306 316 001) to avoid any problems.
The ZF plate slid easily into place and everything bolted up nicely. I found that I had to raise the heat exchanger up a bit to allow access to the trans dipstick , an easy modification.
More here
Hi John,

Beautiful work on your transmission and damper plate replacement. We didn't remove the engine. Just lifted it a touch with an extra main sheet and moved it forward enough to take off the bell housing and transmission.

Do you recall why the shop said to use the OEM Sachs damper plate? It seems much less sturdy than the R&D damper plate. However, I will take your lead to heart and call beta marine where we bought the twin disc as I googled your part number and they sell the OEM damper
https://parts.betamarineusa.com/pro...g8dAvWb--a-qGfhlsCvfoXsVt78r9Hy4eXlcDwj0c5J_s

Thanks so much!

Bert
 

JSM

Sustaining Member
Do you recall why the shop said to use the OEM Sachs damper plate? It seems much less sturdy than the R&D damper plate.
Thanks Bert
When I started researching this project I considered the PYI plate as I thought it would help with vibration problems I was having but as I dug deeper I found more negative info ( Google R&D damper problems) seems most of the problems are with elastomer material failure or fit.
I had some conversations with Beta Marine in South Carolina and they never mentioned any plate other than the Sachs unit.
When it came time to buy Beta was out of stock. My yard recommended Federal Marine Transmissions where the owner Jim confirmed what I had read on the net. If I remember correctly his exact words were " Don't f**k around with anything else, you only want to do this once" ;).
The original plate made it 35 years with only noticeable wear on the teeth. I have four seasons and about 350 hours on the new equipment and all is working flawlessly.

Good luck and have fun !
 

bertboyer

Member III
Thanks again John.

I did google the R&D damper problems and I called Beta Marine who noted that the spring damper plate they sell is not the OEM part but would work fine if the outside drive plate diameter was the same. The OEM part is now pushing $600 and the Beta Marine version is $300. So I am heading out to the boat to pick it up and measure it. I see Federal marine sells several options, but I want to get measurements before I call them.
 

JSM

Sustaining Member
The OEM part is now pushing $600 and the Beta Marine version is $300.
Crazy ! Are you dealing with Beta Marine west or east ? I met Stanley from Beta east in South Carolina at the Chicago boat show a few years back, he is extremely knowledgeable and was a huge help to me when I switched from three engine mounts to four and again with the trans swap.
Jim at Federal is also very good. Make yourself a drink and grab a comfy seat if you call him...he loves to talk transmissions ! ;)
 
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Loren Beach

O34 - Portland, OR
Senior Moderator
Blogs Author
If the OP needs the number of the Portland area Betamarine rep, he should contact me. Ben is very mechanically inclined but is not a diesel mechanic AFAIK.
He installed the same Betamarine 25 in his Cape Dory as I put into our Olson. And, same engine for an E-32-3 in our club.
 

bertboyer

Member III
Thank you both.

Meanwhile, I was talking to Farron at Beta Marine in SC. He wrote a nice little PDF about replacing a Hurth with a TMC 40. He asked about the diameter of my damper plate and it matches his (121.5mm/4.78"). However, I thought he mentioned his was made by Alto. I emailed him to find out.

I then called Jim at Federal and he was having a rough day as his phone and computer were out. He is going to check on his damper plate stock as soon as he can and get back to me. Their website shows similar damper plates, but not the same diameter

I'll give you a call Loren.
 

Attachments

  • CONVERSION FROM ZF 5M (HURTH HBW 50) TO TMC 40.pdf
    343.9 KB · Views: 2

bertboyer

Member III
Update: Beta Marine just emailed back and said their damper plate was the Alto plate. I guess I will wait to hear back from Jim at Federal...
 

bertboyer

Member III
Update #2:

Jim at Federal called me back. Very nice guy and I did need that cup of coffee!

He again repeated that the Alto plate made in China was a piece of C***. He strongly recommended the Vulcan replacement. I can't find the part on their website as it is down, but here is what I believe to be the same unit. It looks exactly like mine.

While Federal is a bit more expensive than Fredwarner, I am still going to order it from Federal as they have 40+ years experience and Jim was great to work with. Very knowledgeable and a super nice guy.

I searched Vulcan damper plate problems and don't see the internet line up like it did with R&D damper plate problems.

All: Please let me know if others have experienced any problems with Vulcan plates.
 

JSM

Sustaining Member
While Federal is a bit more expensive than Fredwarner, I am still going to order it from Federal as they have 40+ years experience and Jim was great to work with. Very knowledgeable and a super nice guy.
Glad to hear Jim was able to help you out. He's a one man show and an absolute savant when it comes to marine transmissions.
The Vulcan damper plate was not an option when I was doing my research but at that price point , the fact that it's made in Germany and Jim likes it you should be fine.

Happy Wrenching !
 

bertboyer

Member III
Thanks again Jim!

I really wanted to support Federal because of Jim's stellar service. I also figured if I ran into a snag, he would be able to help me through it.

Bummer that their phone and internet is out. I need to mail him a check, he has to wait until it clears, and then he will mail it. Old school for sure!
 

JSM

Sustaining Member
Bummer that their phone and internet is out. I need to mail him a check, he has to wait until it clears, and then he will mail it. Old school for sure!
Funny, his internet was also out four years ago, I had to drive out to his shop with a check.

Keep us posted on your progress.
 
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