ENGINE NOISE-DAMPER REPLACEMENT?

[wolfe10]

Leigh,

So, the only change was from the OE polyurethane dampener to the Sacs one-- no other changes needed.

Said another way, the OE polyurethane style dampener and the Sacs are interchangeable with no other modifications.

And, no "Low RPM rattles"?

Thanks.

Brett

[leigh weiss]

Brett,
For my engine, with is own low speed vibration pattern, the rattle is a thing of the past.
The part was a direct bolt in. No changes required.The replacement PYI damper Plate is now on the sale page.
With only a sample of one I don't know if this is the "FIX"
Be sure to use Lock Tight on the mounting screws.

Leigh

[wolfe10]

Locktite red or blue? Do you have torque specs?

Thanks.

Brett

[leigh weiss]

Brett,
I used Blue Lock compound
Torque was 170 inch pounds.
That was based on the size of the bolts and a SWAG as to the proper spec.
I just found the ZF/Hurth transmission technical manual. If you need a copy I can send it as a PDF
It did not have the specs for the damper bolts.

Leigh Weiss Brisa #155

[Capt. Nini]

I purchaced the Sachs part but after talking to Leigh Weiss I called Fred Huchinson at PYI. He convinced me to replace the damper plate with a PYI high deflection plate, part # 22 AA4. It has a 30* deflection, thus better absorbtion, cost $215. Will install 12 November.

Randy Nini
Capt. Nini
#294

[jking]

Hi,
From what I have been reading there are lots of boats with this problem. My boat is very rough for about 20 seconds after engine start, but I don't think it is worth replacing just yet.
Jan #303

[AynB]

Halona is getting her's done this winter. We've over a 1000 hours on the engine and systems so, at the least the mechanic is going to inspect it. We too are going to go to a flexible system, probably one that allows for 30 degrees.
We're doing it out of hand because we've seen what happens when the damper plate goes out. What should have cost this particular boater about $1500 to just replace the damper plate on time ( or on schedule ) ended up costing him about $2700 - mostly because of all the damage that the blown up pieces did. Took the mechanic 10 hours alone just to get the bell housing off the engine.
So I am just gonna do it and waste what ever hours the plate had left on it and replace it with a more modern system. I've already had to replace the transmission ( at just over 500 hours !!! ) due to poor ( read cheap ) design. I really don't want another headache.
Good luck,
Al

[leigh weiss]

To all who are plagued by the "Low speed Rattle"
It seems to me that the problem of chatter/rattle of the transmission seems to be two fold.
A light flywheel by the engine manufacturer for the entire family of engines and a poor choice of damper Universal/Westerbeke to absorb torsional variations this will cause at low speeds.
The quick fix given to us from Hansen Marine and Catalina is to raise the idle speed and or replace the damper.
My guess is that PYI in response to this, has developed a High Deflection Damper to replace the original.
I found that Bata Marine (based on the same Kobota blocks) sells similar marine engines with a critical modification. They install an extra flywheel weight (increases mass) that reduces torsional variations/vibrations. They claim very quiet and smooth operation over a wide range of engine RPM especially idle of 800-900.
Numerous postings on this and other pages have reported problems with low speed transmission rattle.
It seems to me that poor engineering/lack of testing by the original manufacturer is the cause.
I have installed the original PYI, a Sachs and a PYI HD damper. I have run them for about 10 Hours each and report that
the HD Damper is the best as far as reducing transmission rattle .
I can also wonder if the torsional stress is some how reducing the service life of the original dampers.
My experience with Damper life is limited to my 1980 Universal 5425 engine with a Sachs damper and a Hurth transmission that lasted over 4000 hours of cruising
My Catalina 350 engine with 125 hours was a rattle bucket which prompted me to seek the root cause of this problem. I now have about 350 hours and a quiet boat.
I also have two extra dampers PYI and Sachs hardly used.


Leigh Weiss Brisa #155

[wolfe10]

Randy,

Do you have enough hours on the new Damper Plate to give us a report?

Was it an easy replacement for the OE plate?

What condition was your original in when you removed it? How many hours on it?

Have you been able to return idle speed to correct RPM vs raising it to compensate for the OE plate? Result?

Thanks.

Brett

[nybor]

Hello All.

Well, thanks to Jerry, Leigh, et al., I DID IT! It took me longer than the "5 hours" mentioned, but now that I know what to do, 5 is a reasonable time frame. I would allow 10 hours - need a factor of safety (sorry, engineering prof talking here)

Jerry's photos are great and I used them with some additional ones from Leigh to complete the job. I installed the PYI plate and incredible difference. I switched from idle to forward and thought I had screwed up, because there was ZERO noise/clunk - even at idle. However, the dock lines indeed showed that it was in gear (forward and reverse). Not having that noise is so much nicer than worrying about not letting the engine idle...

the only additional things to be aware of and might help speed up the process:

1. I bought an open ended ratchet set from Harbor Freight (thanks Leigh). One of them fit around the nut that is used to lift the rear of the engine. This made raising it a breeze. I added another threaded bolt/nut on the starboard side, but you can simply spin the nut with your finger to take up the slack as the port side is raised. HOWEVER, the bolt had a slight angle to it as it raised the rear and of course as you "rotate" the rear, there is a forward force on the engine's front rubber mounts. It might not be a problem, but I left it like this for several weeks while busy at work/waiting for the new plate, etc. Once I lowered it, the mount bolt did not line up with the holes on the engine. After wiggling/prying etc, I got them in, but slightly damaged the beginning threads of one of the mounts. A quick spin with a die cleaned it up and no further problems.

Removing the plate. I couldn't get the bolts off at first. I finally got one off and saw that whoever installed it used Locktite RED. McMaster Carr sells a "high torque" allen wrench ($0.38) that I used in conjunction with a mini-torch to heat them up. The remaining bolts them came off.

Had a lot of grief about the drip less shaft seal and its collar. I did loosen it and eventually slide it backwards maybe 1/2 inch, but I think it was already pretty far back. I used new set screws (another Leigh suggestion) and no leaks. However, if I grab the bellows and lift it up, there is a leak. This I am told is normal. I ran the engine in gear and no leaks so fingers crossed.

last but not least. I did the entire job myself, but a helper would help getting the tranny out but more importantly back in.
To line up the spline, bolt holes and alignment pins while holding it by oneself was not fun.

Bottom line. It can be done and it is a rewarding job knowing that you don't need a mechanic to help. (now watch me sink when I take her out!)

dave
#414

[hansgrasman]

On March 4, 2012 Jerry Ross published a detailed list of the replacement procedure for the damper plate.
I gave a mechanic a hard copy of the replacement process but he never did show up to tackle the job.
It was my only hard copy and the posting of March 4 will not activate the links of the exhibits the exhibits which Jerry provided.

Is it possible to resent this again and enable the links to the exhibits ?

We have other C350 owners who are interested in this subject.

My transmission does work but has a clatter sound and I know it comes from the damper plate.

Look forward to a reply

Thank you

Hans Grasman
Belcourt165

[KenKrawford]

Hans, I think the information you need is in this thread - http://www.catalina350.net/phpBB3/viewt ... f=11&t=685

[nybor]

One more cautionary note if you decide to do the plate replacement. Take the time to remove/move as many hoses as you can before starting. I didn't and sure enough, several constantly got in the way! You shouldn't have to work AROUND flexible hoses.

[Palmettomoon350]

Palmetto moon only had 750 hours and the noise was becoming quite loud. After searching the forum I came to the conclusion the damper plate was the culprit. Another owner here in Charleston replaced his damper plate but could not move for several days, very tight working space. Virtue being the better part of valor I found a mechanic to do the job. While he was working he also removed the heat exchanger and cleaned it out, and drained the transmission fluid and refilledl. He was extremely thorough.
Once the work was done I could not believe how much the noise level and vibration had been reduced. The damper plate itself was complete mess. It's no wonder it caused the amount of noise and vibration. The piece in the center came out in chunks.

Carl Beckmann
Palmetto Moon # 223

[russp]

Hi Carl,

Quick question, what damper plate did you reinstall? Manufacturer, part number, etc?

Regards
Russ Peel
Avalon #150

[TBOT422]

I just ordered the high deflection plate from PYI. According to them, the part number has changed from RD22AA4 to RD22AM4.

Gary,
Westerbeke installs the 22B4 as stock on that engine (OEM Westerbeke 044624). Going with the 22AM4 (formerly the 22AA4) will give you additional deflection and make a smoother ride at lower RPM's. I had quoted the 22B4 based off of the OEM # provided, this part should work but if you would like the additional deflection then the 22AM4 would be the way to go. This has a list price of $170.00 as well.
Best Regards,
Kenneth Planck

Now I can start planning the rest of my "Winter Project".

[russp]

Hi All,

Yet more info on damper plate. Mine has had an unpleasant "rattle" at idle -> 1100 rpm for some years so based on all the info in this forum I decided while doing work recently to replace it, and ordered a 22AM4 high deflection damper.

When we pulled the old one out it seemed perfectly sound, but - there is a washer, about 2" diameter on the input shaft sitting behind a circlip. This was loose and just bounced around by finger rattled loudly and we "presume" was the source of the rattle. Put new damper plate in and the rattle is certainly gone, but was probably only a nuisance and not any risk to the gearbox anyway.

C'est la vie! At least I know now that it is in good condition, and at 1200 hours flushed gearbox thoroughly while out and no sign of any metal flakes so also good to have been able to find out.

[leigh weiss]

Russ,
I also found that excess play in my OEM damper plate. I used automotive king pin bush washers ( they come in thicknesses every few thousands of an inch) to reduce the end play. After installation the rattle was still present. Then commenced the testing and discovery of the high deflection damper from PYI .

[Dutch]

New Damper Plate (Sachs 1866 061 001) is quieter than the R&D 22B4 for my engine and transmission
Motored for an hour and returned to the mooring "quietly". All is well with the world.
"Brisa" #155

[leigh weiss]

the last post above is a repeat of an old post. I tested all three damper plates (sachs, PYI standard and PYI High deflection) to rid the transmission of the dreaded "rattle'. The results were the High Deflection damper was the cure, hands down. The Sachs made some
improvement over the OEM plate.. Had a lot of practice replacing the dampers, and that's how a came up with the average change out time of about 5 hours. I don't know why this post is now re-posted, but if I can help anyone with the damper replacement instructions let me know.