Twin Disk transmission on 3208 TA

[Gypsymagic]

I recently completed a rebuild of a single engine Cat 3208 TA 375 HP with a twin Disk transmission. (Transmission was rebuilt with new clutch and seals, all internal was found to be in good shape)
Not being familiar with this transmission when we did the sea trial I noticed an unusual to me, bang that jolted the entire engine when it went in gear, both forward or reverse. The damping plate was also rebuilt.
Thinking there was something wrong, the mechanic that rebuilt the transmission connected his pressure gauge and these were normal. He contacted TwinDisk and they told him this was normal, they verified this with an email to the subject.

My previous boat had an electronic ZF and these engaged very smoothly.

Anyone with these engines have an opinion?

Thanks

 

[twistedtree]

Damper plate is the first thing that came to mind, but you say that was "rebuilt". Do you know what model TD transmission? I have an MGX 5114 with electric shift valves and it shifts smoothly.


Does the gear or engine jump around at all when you shift? Maybe a bad engine mount?

 

[Gypsymagic]

MG 507 Twin Disk built 1996.

Yes engine tends to jump a bit, motor mounts are new and engine was completely aligned.

 

[heysteve]

I have a TD 506 on my 1984 3208 natural and it too bangs into gear. There is a momentary drop in hydraulic pressure then back into the green. I’ve been told this is normal.

 

[psneeld]

Lived on a 37' sportfish with twin 3208 TAs and twin discs for 3 years/ran it for 6.... if I engaged both engines at once in idle, it would nearly knock you off your feet.

Don't remember a bang or loud noise, but the sportfish produced enough noise and from the flybridge it might have been the and never noticed.

 

[Gypsymagic]

Do those that replayed to my question on the “bang” shifting of a Twin Disk 507-1, I enclose a reply on the subject from the TD major distributor and representative in the US:

WE WILL HAVE TO LIVE WITH THE NOISE, HE DID VERBALLY SAY THAT IT LIKELY WILL REDUCE THE SOUND AS THEY GET OLDER AND MORE USAGE. MINE WAS JUST REBUILT.

Robert


From: Matt Goldstein <mgoldstein@glpower.com>

To: >

Date: 10/27/2023 1:36 PM EDT

Subject: MG507-1 Harsh engagement






Robert:

Following up with our phone conversation on the MG507-1 engagement.

The standard MG507-1 is not equipped with a priority rate of rise valve, therefore they do not have a smooth engagement.

When shifted they instantly send full pressure to the clutch, which engages with authority.

There is typically an audible clunk.



We have plenty of people on both sides of the fence on this.

Old timers have a hard time knowing the gear is engaged on the new smother PROR stuff.

People with more experience with the PROR stuff call concerned that there is something wrong with their MG507-1 units because of the harsh engagement.



Switching to an MG5075 with PROR will give you them a smoother engagement.

Switching to the MGX5075 with a Twin Disc control system will give them the smoothest engagement in the industry.



Let me know if I can be of further assistance.



Thank you!



Matt Goldstein

Technical Service Manager

North Atlantic Power Products

15 Continental Dr.

Exeter, NH 03833

Ph: 603-418-0470

Fx: 603-418-0471

email: mgoldstein@glpower.com

web: www.northatlanticpower.com

Great Lakes Power Group

 

[Delta Riverat]

Banging into gear is something I'll never miss from my outboard (dog clutch) days. Shift fast, you don't want to hammer the dogs smooth. One clunk is what you want.

The Hurth 630's on my boat make no noise and no jerks. When engaged the boat responds. The only tell is a slight change in engine speed and sound.

 

[Slowmo]

I don't know if this helps but I know my Twin Disc gears shift smoothly IF the idle speed is 700rpm or below. This is probably because the pressure drops off a bit. At higher RPM the shift is abrupt. Also yes, there is a momentary pressure drop during shifting as the clutch actuator fills. I had BW Velvet Drive before, it was about the same.

 

[C lectric]

My TD 506 also bangs into reverse. Usually only once on the initial reverse shift.
It is a 1976 model with about 7000 hrs. on it. On subsequent shift to reverse no more noise.

 

[Pascall]

I had the same problem with a Technodrive link.
I applied an Accumulator and now the bang is a lot less.

Greeting

Pascal.

 

[twistedtree]

The response from GL Power explains it. Some gears have restrictors in the oil passage that causes the pressure to rise more gradually in the clutch pack when you shift into gear, and that causes a more gradual clutch engagement. It's like feathering the clutch on a car (if anyone still drives a clutch car) rather than popping the clutch.

 

[Pete Meisinger]

Normal or not, accepted by the factory or not, I wouldn't have it!

I also cringe every time I hear someone "ease" an outboard or stern drive into gear.

Does it help at all if you "shift it like a man".

pete

 

[tiltrider1]

The response from GL Power explains it. Some gears have restrictors in the oil passage that causes the pressure to rise more gradually in the clutch pack when you shift into gear, and that causes a more gradual clutch engagement. It's like feathering the clutch on a car (if anyone still drives a clutch car) rather than popping the clutch.

Manual transmission are currently the best car theft deterrent in Seattle.

 

[Steve1.0]

"Manual transmission are currently the best car theft deterrent in Seattle."


:lol:
I think that's true nation wide.


My 1992 TD's bang too. Also a second or two delay going into reverse. That worried me when I first bought the boat. Cat told me its normal.

 

[greatpapabear]

Good morning, Gy.psymagic.

You describe exactly the symptoms I found in 2006 with my port Twindisc box. Calling the main company in the UK, they sent an engineer to verify what was happening.

In next to no time, he said the issue was a too rapid engagement. He inserted an additional spacer on the idle pressure, and lo and behold, a smooth engagement. he left me with some spacers if ever I felt engagement needed further adjustment.

 

[Patrick4002]

td from 1990

i have 3208ta 435hp version with td507-1
the boat is made with 2 handels for the clutch and 2 handels for the fuel ( 2 engines)
i have the boat now for 4 years and in the beginning the port clutch needed 2sec to engaged this now less then 1 sec
i have no bang on the td's the motor speed is 600rpm-650rpm when switching gears. due to the 4 handels i can switch from neutral to forward /reverse quick
when switching from forwards to reverse i wait a few sec in neutral

i had a inspection from cat on the motors he told me that it was normal for having a delay (in the beginning we had the boat) due the boat had been moored for a few years without sailing.

he said it will get better after you sailed a few hours on 3/4 power so the td get heated well and the oil channels are good flushed when mooring.

 

[MYTraveler]

Bang is a relative term, but I hear and feel, from the pilot house helm, when I put my twin discs in gear, even one at a time. This on a boat that is so quiet, I have to strain to hear whether the genset is on (in fact, once I left the boat without turning it off). I have electronic controls which have a "smooth shift" setting. In that mode, you can't feel a shift. But I never use that mode as I prefer to know when I am in and out of gear (coming out of gear can be felt, which isn't surprising since it idles at almost 6 knots), particularly in close quarters maneuvering. It is comforting to feel the response.

 

[Patrick4002]

i dident think of this

Bang is a relative term, but I hear and feel, from the pilot house helm, when I put my twin discs in gear, even one at a time. This on a boat that is so quiet,.

about the same, we have a very good sound isolation, we don't hear the genset
(onan 12,5kw) and if we shift in gear we travel almost 7knts its even hard on inland channels as the max is 4knts

Best regards,
Patrick