Hurth HSW 630 A1-1.6 (ZF 63A 1.56/1.58 Ratio 8 degree DA

[Skipper Dick]

I've finally concluded my port transmission is making way too much noise. It could have been that sand bar I ran onto while shooting the breeze with a friend sitting on the bridge with me and not paying attention to the markers. Who knows, but one of my local ZF dealers tells me that the unit can't be re-built economically so I have to buy a new one. It only has a little over 600 hours on it.

Does anyone know of anyone who can rebuild this tranny here in South Florida or is this guy being straight with me. I'm pretty sure I can pull it without removing the engine.

Thanks for any help on this.

Dick

[scenarioL113]

I would get a second opinion. What does he want for a new unit?


http://webcache.googleusercontent.com/s ... clnk&gl=us


that should give you some sort of a baseline. Talk to a transmission shop that does marine, forget the dealer he want to sell you a new one for 3 grand!

[scenarioL113]

This overhaul kit is $335
I would think a fair price to rebuild would be $1000 total. A pro could rebuild it in a few hours. The unit need to be brought to him.


http://www.halemarine.com/index.php?mai ... ts_id=2474

What is wrong with your transmission? Is it something burned up or is it broken. If it is damaged and "Hard parts" are involved then it may not be feasible to repair.

The unit should be able to come out but the rear of engine will need to be raised because you need to clear the shaft coupler when pulling the unit from the bellhousing. The trans input shaft is stabbed thru the flywheel spline a few inches would be needed.

Unfortunately the unit needs to be taken apart and evaluated to see what is wrong.

My father is a retired transmission guy. He lives in Altamonte Springs and if you brought him the unit I am sure he would disassemble it and atleast let you know what is wrong with it.

PM me if you think you could get it to him. I am not sure if he would be interested in rebuilding it but atleast you would know where you stand. It would be disassembled properly and if rebuildable you could take it from there.

[Skipper Dick]

Frank,

It had a typical knock if the RPM fell below 600. I did have a problem with that port engine running rich for a while, but a good dose of SeaFoam down the air intake of the Merc Horizon and some in the tank took care of that, but the big difference occurred when I ran into shallow water at 21 knts only to come to a quick stop. I'm thankful that I didn't yank all my running gear off, but the shallow water was mud and sand.

Since then, there has been a clunking noise in reverse and a knock in forward. The noise would go away in forward if I even advanced the throtle for a 20 RPM advance, but in reverse it is still clanking. In nuetral, it will knock until the engine stabilizes at 610-620 RPM. The alignment is near perfect and the engine runs great, but still the noise that you can easily hear with the engine hatch closed.


I don't trust the tranny to take her off shore now, and I don't even want to run her in the river, so I am on a quest to get it fixed or get a new one. I did find a new one on line for $1,000 plus shipping and the seller claims it is still in the box. I made an offer, but have not heard back yet.

So, I am starting tomorrow to remove the stuff in the way. The starter, disconnect the oil lines from the cooler and the cooler, the linkage and the neutral switch wires. My prop shaft and coupling will back off about 3 inches to the dripless and I can put a come along on a 4x4 across the top of my lift to raise the engine after I loosten the horizontal motor mounts in the front so it will rotate up.

Anyway Frank, I've got a couple of other irons in the fire, but will still consider your father. Altamonte Springs isn't that far away from where I am.

I gotta keep my eye on those sticks in the water. I've been down here for 10 years and can't seem to get used to all this shallow water. In Alaska, I had Fjords and 600 feet of water right off the small boat harbor in Seward. The only thing I had to worry about was hitting ice chunks from a glacier.

Hell, I guess I needed something else to get me soaking ass wet with sweat down here in this hot sun.

Dick

[Bruce]

The drive plate is made to take the brunt of sudden stopage and in/out gear action. Loose or broken springs can make it sound as if the engine is comming apart especially at low rpm's.

Beside making a diagnosis without pulling it apart is like trying to time a gas engine by ear.

I'd quit guessing and pull it to check the plate first. If the bell housing has a removable rubber cover at the top, barring the engine over by hand while looking in there with a flash lite might show something without pulling.

Thats a stout gear. While I've seen em go at times, I seen many more attached to mangled shafts and props contimue to work just fine.

The only way that gear would not be economical to repair is if you have to replace shafts and bearings.

Also check your coupling and make sure there is no lateral movement to it or coupling bolts loose.

Warning: don't take the gear to anyone who is not familiar with that gear design. Bearing preload is important when those case halves are put back together.

[Skipper Dick]

Bruce,

Thanks, I'm checking for a removable rubber cover ASAP. I've never seen one, but I could have missed it. After that, I'm pulling it and through guessing. I want it right and that is my goal.

Dick

[Bill B]

Hi Dick,

I have the same trannies but the 2.0 ratio. Running Yanmar 6LPs on my B31. I too had the same symptom - rapa tap at dead idle, and if I advanced 100 rpms it was gone. No rapping all the way up the scale. No slipping.

I had a ZF Hurth tech out to the boat and he said "nothing wrong". He thought it might be the damper plate. Next I had a Yanmar tech out. Indeed it was the damper plate - the rubber bushing between the two plates had torn.

Anyway, food for thought. Once you get the tranny off you are basically starring right at the damper plate. Not sure if your Mercs have use rubber or springs in the damper plate.

Good luck,

Bill

[scenarioL113]

Those symptoms CAN be from the damper / flex plate / coupling / drive plate.....whatever you want to call it.

Those are the symptoms they warn you about if you dont use the recommended drive plate.

When you pull the unit check the spline are to see if it is beat up on the drive plate.

My transmissions clank a little at dead ide especially when putting in and out of gear.

[In Memory Walter K]

Your idle is too slow. You have transmission "slap". I had a similar problem when I had Chrysler 440's. 50 more rpm's cured it. Also, check for anything that might have loosened by virtue of the impact of your grounding. It would explain the noise in reverse. Might not even be the tranny.

[Skipper Dick]

Bill,

I wouldn't be concerned at all if it was just a knock at idle in nuetral and it would stop once the RPM was advanced a little. And now that I've got that port engine purring and the ecm has it idling at near 650, it hardly makes a noise at all until I put it in gear.

So thanks guys for all your suggestions and I'll certainly pay attention to the damper when I get the tranny sitting on my dock. Maybe I'll luck out and just have to replace the damper. Since the engines and transmissions were a package deal to the former owner, I just assume that they would use the correct damper. You'd think anyway.

Dick

[scot]

I don't think the noise is uncommon to ZF gears at low speeds. Seems like I recall Tony Athens writting about it in a Boatdiesl.com post. You may want to post your concerns on the Boatdiesel site in the ZF section.

BUT....

I don't trust the tranny to take her off shore now,

For me that would be the real issue. When I head offshore I need complete confidence that "all is well", or I spend the day worried vs enjoying the trip. You know your boat better than anyone else and you know that something has changed.

I've been running single engine boats offshore for years, the one I'm building is a single. But I treat them like single engine airplanes, if something isn't exactly right I don't leave the jetties.

If it takes a new gear to get the confidence back, so be it, find a new gear and enjoy the days on the water more.

[Skipper Dick]

Scot,

Yes the confidence level is down. If it was just a little clicking noise, I would just shrug it off as a trait of this transmission, but people on the seawall can hear the noise as I motor by. I'm hoping that it may just be the damper.

Dick

[Brewster Minton]

I would bet its the drive/ damper plate. I had that happen to me. Had to pull the bell housing. Pain in the butt, but it cost less than a new tranny

[Carl]

Get into it already.
Proceed with the objective of replacing the tranny, possibly rebuilding but hoping its the Damper.

A soft landing in mud shouldn't have gone further up the drive train then the damper.

A bad Damper can make a simple fix seem like a huge problem. Came out of the water one year everything was perfect...they dropped me in the following Spring, cranked right up, put her in gear all was well till I went until I went to pivot out of the well...then it sounded like I blew an engine.

Got my fingers crossed...now get into it already...it may be nothing more then a damper swap...but it ain't gonna fix itself. ( and I don't mean isn't)

[Jishu]

Get into it already. GBWhatsApp APK
Proceed with the objective of replacing the tranny, possibly rebuilding but hoping its the Damper.
Got my fingers crossed...now get into it already...it may be nothing more then a damper swap...but it ain't gonna fix itself. ( and I don't mean isn't)

Hearing these posts made me cross my fingers. Guess i have to fix it as well or there will be a more bigger problem.

[Carl]

...talk about reviving an old post! July of 2010.


Good luck and check back with the results.

Carl