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Squealing Hurth HBW 10 - ZF 12 transmission tranny

When i purchased my morgan she would not smoothly go in reverse. A week later I tried to back out of my slip and ended up in the marinia behind me with no way to stop ! .I called the ZF people and purchased a ZF 15 three days later UPS to my front porch ! 1.5 hours the mechinic had it on and working smoothly ! That Hurth 10 was at its max load from day one. ! But did last 30 years. So I went better.
 
Lee
I'm not having shift issues....I lose drive once the squealing starts, it's simultaneous with the squealing.
It's after running for 15-20 minutes. Maybe heat related in the tranny...I just don't know. Can't seem to find a mechanic who can say...ah...I know what that is. I have a recording of the sound. But when it happens I shut everything down immediately...I don't let it go for more than 10-15 seconds...bottom line when it happens we lose our ability to motor. Once I let it "cool" for 15-20 minutes I am able to run Again for a little bit...then repeat the whole process again. If I were to be in any kind of chop or waves I wouldn't be able to motor at all.
The tranny with ne damper plate is from Atlantic Deisel ...brand new not rebuilt. Everyone I have talked with says if it were the cutlass bearing it would rattle, vibrate or shake. It doesn't do that ...the shaft is in alignment according to the yard mechanics...
 
John ,Trans Alantic Deisal are the real deal, as far as i understand the Hurth folks are no longer in bussiness and ZF folks baught them . Have you changed oil in the transmission ? My damper plate is origional I sorta remember 1,500 or so for just the trans..
Are all the bolts tightened on the motor mounts ?
Do you run your blowers when the engine is on ? I run my blowers both of them every time the engine is on. I replaced the blowers with the high speed ones new alu blower tubes and New clamshell vents. Keep the air moving all the time around that engine. ! Best of luck
 
Yes...it's the ZF12. The squeal shuts me down and is from the prop literally coming to almost full stop. I imagine it would stop anyway if I just kept it in gear rather than shifting to neutral then shutting the engine off but I don't want to damage it. It's an awful sound. I sent a recording of it last year to Jeff Lovett.
The mounts look good and all else is tight. Yes, always run with blowers on. It's not the belt. Remember...it's after 15-20 minutes and it stops the forward propulsion. Anyone would do the prudent thing and shut it down quick. Looking for any ideas from the mechanically inclined or have had this experience ....Could a cutlass bearing squeal? It's a high pitched sqeal that drops in pitch as it slows down.
 
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I once had a cutlass bearing spinning. The set screw had come loose. It made a lot of racket but never stopped the shaft.
 
Thomas
By a lot of racket...do you mean vibration or a very loud high pitch singing squeal...until it bogged down?
 
tfrere said:
It was not high pitched. It was more of a grinding sound.
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This is a distinct descending "note" as the engine slows down from the resistance...as soon as it's put into neutral...the sound is gone. But we don't shift back to forward. We wait 15-20 minutes and proceed at about 3-4 knots. If there is any headwind, waves or chop...it's a no go...but then we can usually sail our way back home...at least close enough to motor the last 1/4 mile or less to our mooring.
 
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I think it would be worth checking your cutlass. Dive under the boat and feel it as you spin the shaft in neutral. That's how I figured out what my noise was.
 
John,
I could actually hear it when the shaft was spinning in neutral while sailing. Of course that may or may not work with a feathering propeller.
 
tfrere said:
John,
I could actually hear it when the shaft was spinning in neutral while sailing. Of course that may or may not work with a feathering propeller.
Click to expand...
This only happens when in gear (forward or reverse) after 15-20 minutes...it seems heat related.
 
terry_thatcher said:
Need to replace the transmission. Not a hard job, but device will cost $1500 or so.
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Terry...
I guess you didn't catch that we just put in brand new transmission ZF12 from Atlantic Deisel and the new damper plate. Shelton Sawyer sounds like he had the exact same issue after discussing it with him...the cutlass bearing is what we believe now is and has been the problem. Going to replace it. Too bad we can't look at the old tranny to see if there was any damage.
The new transmission is still under warranty though and works.
 
John, I don't think you have enough motoring hours too wear out a new Trans. Any component can fail of course. What you describe sounds like a bad trans bearing. Questions:
What & when was the last work done on trans, shaft, or seal?
Have checked the trans fluid level? What does it smell like? Burned smell? The ZFs hold a small amount of oil, important to change and use a quality oil. But even when new, the fluid smells God awful so don't be confused. Compare w/new If you can.

What do you use for a shaft seal? Traditional packing or a PSS type? If someone REALLY overtightened a traditional packing collar it might squeal from lack of water. You should see a drop from a traditional packing if adjusted properly.

A cutless bearing is simply a bronze collar with a 1/4" rubber sleeve bonded inside. Your engine alignment needs to be really off to eat thru the rubber. Look at the spinning shaft through the 1/4 berth. Is it moving up & down? Carefully touch it with a soft screw driver handle to see if it's bouncing up and down.
 
We replaced with new trans last fall.
Fluid is fine and brand new...one week old.
PSS seal. Lots of water coming in if I slide bellows aft. So there's water for lube.
Cutlass has not ever been changed as far as we know. This has been an on again off again issue that rears its ugly head every once in a while but consistently now. 15-20 minutes of forward at 5 knots and ...it hits the high note and then as the engine rapidly starts to slow as if a giant hand was grabbing the shaft the "note" loud! descends in pitch. We quickly go to neurtral and it stops immediately...Shelton Sawyer had exactly the same scenario and it turned out to be the cutlass bearing.
 
This thread appears to have been solved! It was not the transmission at all. It was a worn cutlass bearing. I was suprised how hard it was to find anything in searches about what could cause it. Even knowledable mechanics (I guess not that much) were off on fan belts, damper plates, engine, but a few were right...cutlass bearing heating up causing friction and resistance...thus squealing. Explains why it wasn't happening when the water was 49 degrees!
 
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