Prop slipping on shaft? No...transmission is slipping. See update 4

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McFly
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Prop slipping on shaft? No...transmission is slipping. See update 4

Is it possible for a propellor to slip on the prop shaft?  Where the shaft is turning but the prop doesn't?  

Today I will change the trans fluid and re-check.  Next step is to remove the compass and look for anything obvious at the shift lever connection.  Tomorrow I plan to snorkel on the prop and inspect visually.  Previous posts describes adjustments I've already made at the transmission end of the cable.  Any further suggestions is much appreciated.

Mike

 

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

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Chachere
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There is a key that fits in a slot in the prop and as well in the shaft, to mechanically bond them. 
Can't imagine how it would disappear.
 

Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY

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Catboat Willy
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Mike;
 Whatever you do ...do not get under that boat with the engine running !

Bill Dolan 1990 Catalina C-36 MKI - Hull #1041  'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte  Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'

 

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bakerha
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I know this seems obvious but a quick check would be to shift into gear and observe the shaft coming out of the Transmission.  If it's turning - the prop has to be turning unless it was installed without the key.  If it's a cable or transmission thing - the prop shaft may not be spinning. Don't have to get wet for that.

_____________
Harold Baker
S/V Lucky Duck
Duncan Bay Boat Club
Cheboygan Michigan - Lake Huron
1989 C-36 mkI TR/WK M25XP

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alfricke
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Only time I have ever heard of a situation where the shaft turns but the boat does not move is when a buddy of mine lost his prop all together. He found it on the sandy bottom in clear water (Sea of Cortez) where he was anchored. He thinks it came off while setting the anchor. He’s not sure why the cotter pin did not hold, possibly because it had not been replaced during his last haul out. Keep us posted.

Al Fricke
S/V Jubilee San Francisco Bay
Catalina 36' MkII  #1867
Universal 35-B

McFly
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Hi all.  I have been at the transmission end of the cable to make adjustments, manually throw the tranny into gear, and to observe the shaft turning whenplaced in gear.  There is a distinctive pop (engine off) when going in to both fwd and reverse, so it seems to be shifting from neutral.  It seems that the fwd gear has an issue.  Is it possible for the fwd gear to be "partially" engaged, whereas I get shaft rotation but very little torque? 

I can only describe the phenomenom like this:

Imagine its dead calm.... you shift into fwd gear, the boat seems to move ahead VERY little, but there is some movement.  The shaft is in fact turning, and the engine responds (rpm increases), but there is little to no fwd thrust.  I bring it back to neutral, reduce rpm to dead idle, try again.  This time it goes in to gear, which I know, as I can feel it in the helm (slight grab) and the boat moves ahead as you would expect.  Two very distinct results.  

I have made adjustments to the cable at the transmission end.  I have changed the ATF.  What's left to try?  

I have NOT pulled the compass off to inspect the cable connection at the shift lever, as it seems to be doing its job.  Am I out of options?  New tranny?

Here is a video clip of me at the transmission manually moving it in and out of gear.  Note that you can hear a subtle difference between being in REV and FWD.  This may indicate to me that the engine is "loaded" when shifting in to REV, but not when going in to FWD?  Maybe I'm hearing things.  (never a problem shifting in to REV from the helm).  I'm about at the end of my rope with this....

https://youtu.be/BggLYpf39XQ

Mike

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

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Chachere
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The link to the video does not seem to work.

While we have not experienced this problem in our boat (yet...!), I just did a Google search on the phrase "hurth transmission does not always engage" and found many discussions of this problem.   See, e.g. www.cruisersforum.com/forums/f54/hurth-gearbox-loss-of-drive-in-ahead-but-fine-in-astern-118095.html

 

Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY

mikeannikki
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Posts: 26

Mike I see nothing here as to the type of prop you have??  Do you have a feathering or some kind of mechanical prop?  If you don't and the shaft is spinning then I wuold check to see if PO put prop on without the key??  If you do have a feathering shaft and the blades have any play in them that is prob your culprit.  When we purchased SlipAway she had a feathering prop that the bearings were shot.  Seemed like she would work in reverse pretty good but was at lower rpms a bit wishy washy.  I made a lamp out of my prop and prop shaft(shaft was bent longer story), actually did!  I purchased a 3 blade fixed prop and love it.  We are not racers and I lock in R when under sail,  have never been able to notice any loss in speed (although I am sure there is slightly) due to dragging prop through the water.  My 2 cents worth.  Good luck!  

Mike and Nikki Willis
1996 C 36 #1570  "Slip Away"  
MK II - Tall Rig - Winged Keel
Fremont, Ohio

McFly
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**UPDATE**

Thanks everyone for the suggestions and the wealth of knowledge.  Here is where I stand with this:

First off:  9" 3 bladed, fixed, RH prop.

I brought a friend to the boat on Monday to help me trouble shoot.  I could NOT duplicate the problem.  I have no explanation for why the sudden change in reliability.  On the mooring it went in to fwd 10 out of 10 times!  To ensure it wasn't temp related we brought it out for a motor and made sure the engine/trans was warmed up. motored around for 20 mins or so.  NO ISSUES!  I changed the trans fluid the other day, using synthetic.  Could this have been the game changer?  The ATF I removed seems a bit on the darker side, but this is my first time doing this so I'm not sure.  The PO estimates that it had been 2-3 years since last change, possibly 100 hrs.  The total time on the tranny is currently only 432 hrs (engine and trans).  I sent the ATF out to a lab for analysis, I'll let you know what that tells us.  See attached pic of the old ATF, let me know if this looks dark or fairly normal for 100 hr ATF.

Thanks again everyone!
Mike

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

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Catboat Willy
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Mike,
One thought that comes to mind is that burned transmission fluid tends to polish the plates within the transmission. This is why, every now and then, you'll hear the story that folks add 25% diesel fuel to their transmission fluid when the transmission starts to slip - and this only as an emergency measure. The diesel fuel tends to clean the glaze off the plates and ends the slippage problems. Let's hope the syntecic ATF will remedy your problem in the long term. I change all fluids, including anti-freeze once per year regardless of how many hours. My motor oil is changed every seventy - five hours and I install  good oil filter.
As an aside, I started using K&N oil filters and they are $15.00 each rather than the $7.00 NAPA filters. I was supprised to see  how much cleaner the oil was at the 75 hour oil change. ​
 It's cheap insurance.

Bill Dolan 1990 Catalina C-36 MKI - Hull #1041  'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte  Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'

 

McFly
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Posts: 200

**UPDATE TWO**

Went aboard today, this time along with another forum member (huge thanks to him!). Since I had little frame of reference, when watching from the transmission end he noticed that when going into gear, there was some delay, almost a 'spool up', for the shaft to get up to operating RPM. The occurrences seem to be way down so it seems the synthetic certainly helped, as the problem seems much less frequent now. Although, it did it once today. When putting it in gear, and seeing that it did NOT go into fwd, I just waited, with some power added. After about 5 seconds like that, there was a definitive change to the sound of the engine and the boat moved ahead. So there is internal slippage! I feel confident now, largely due to the assistance I received today, that this is the problem. It was eye opening to go to HIS boat and observe his transmission instantly bringing the prop shaft up to speed, zero spool up.

Next I have to decide the proper course of action. Bill suggested adding 25% diesel to attempt to clean out the inner workings. I may try that. Any other options? Rebuild kit? New tranny?

Thanks again for all the help!

Mike

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

McFly
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**UPDATE 3**

I removed the synthetic ATF and added 25% Sea Foam Hydra Tune additive to fresh Synthetic ATF.  I have now run the engine for about 45 mins with the additive.  It seems to be improving.  The trend of successful first-time command in to fwd gear continues.  It's becoming harder to show the slippage to someone when I have them aboard.  

How long do you think I should run this additive in the ATF?  I was thinking the 45 mins would be about enough and I would change it out to pure synthetic next time I'm aboard.

Curious the forum's thoughts....  

Thanks again.

Mike

ps:  here is a link of the Sea Foam additive if you are curious

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

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Catboat Willy
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Mike; 
I would think the answer to your question is best answered by the Tech Service Department at Sea-Foam since I see that they recommend adding it to your regular transmission fluid to prolong its (the fluids) life. You mostly have a transmission that is slipping and will need replacment in the future.
 I'm following your posts to see how you make out. Best of luck with it & keep us posted.
Bill

Bill Dolan 1990 Catalina C-36 MKI - Hull #1041  'Williwaw'
Std. Rig, Walk Through, Wing Keel
M35, Oberdorfer Conversion,
Home Waters; Charlotte  Harbor & The Gulf Islands of Florida
'You are never out of work if you own a boat'

 

Wally-1840
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Posts: 117

Here’s my experience:
Years ago I had a 30’ Pearson with a Yanmar 2 cylinder inboard engine. I was leaving an anchorage when I felt the engine shuddering. Sounded like the engine was “missing”, maybe running on one cyl. This symptom didn’t go away. My marina couldn’t get the time to look at it. I called, (I was at the boat),  Mack Boring, the Yanmar distributor and repair center. I got a tech guy who knew his stuff. He said to start the engine, put it  in gear and when the shuddering happened to push the shift lever forward a bit. He said if the shuddering stopped it was the clutch and the trans needed rebuilding. Sure enough,  a bit of pressure on the lever and all was quiet. I removed the trans, overnighted it to Mack and had it back and installed in 3 days! 

I certainly dont don’t know if that’s what’s wrong with your trans, but I’m guessing a repair is in the offing. With our boats, holding the gear shift lever with some pressure beyond “normal” might be impossible because as at least with mine it hits the pedestal guard. 

Best set of luck, keep us in the loop.

Wally
"Onanne"
2000 MKII, deep keel, tall rig
​Lake Champlain
 

McFly
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Posts: 200

Hey Wally, yeah, mine hits the pedestal too.  I've read, can't remember if it was in the Catalina menu or the service bulletin, that hitting the pedestal was "normal" and acceptable, as the Hurth did not have a detent for fwd or reverse, just neutral. Terrible design.  I think you're right though, im due for a new transmission.

Mike

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

McFly
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Posts: 200

**UPDATE 4**

After running the motor with the Sea Foam additive in the transmission for about 45 mins, changing out the ATF with the additive and going back to pure .35L of synthetic ATF, there continues to be improvement.  There is still a slight delay, about a second, before the clutch "grabs" and the boat propels ahead.  This is a marked improvement over the much longer delay, which ranged from as quick as 5 seconds to as long as never.  I'm hoping this continues to be manageble and I can get through the season this way.  

Here is a video clip of the transmission in action.  You can see and hear the slight delay (turn your volume up).  This time the link will actually work.

https://youtu.be/itQSNWMBejU

My question has become this:  Rebuild the Hurth or buy something new?  Curious your thoughts.

Mike

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

Wally-1840
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Posts: 117

Hi Mike,
I also never liked the shift lever hitting the guard, so I took it off and had a machine shop “bend it” to a “straighter” shape. It didn’t take much. I didn’t want to do this myself by just putting it in a vise and cranking on it. Besides, I assumed it’s stainless and would probably need an arbor press. It doesn’t hit the guard now but still has a “bent” shape.

Wally
"Onanne"
2000 MKII, deep keel, tall rig
​Lake Champlain
 

McFly
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Posts: 200

Wally, I would love to do the same. Next time you're aboard would you mind taking a picture and posting it? I now have a relationship with a local metal fab shop after I bent my nice Magna grill at the fuel dock! (long story but the trans problem was a factor). Anyway, I had him do some metal bending for me, so I may bring him the shift lever. A pic of how it "should" look would be handy. Thx again!

Mike

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

Wally-1840
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Sure, be glad to, although the bend is quite subtle.

Wally
"Onanne"
2000 MKII, deep keel, tall rig
​Lake Champlain
 

BHamster
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Posts: 19

Last year my transmission died.  After reading that several forum members had recurring problems with the original Hurth100 / ZF10 I decided to upgrade to the ZF-15.  It has significantly more load capacity (translates to more durable), and in my case was actually less expensive than trying to buy /rebuild the original.  Now with a couple of hundred hours on the new unit, I am very happy I made the switch.  See ​Transmission Upgrade - Asking for opinion. 

I think it's very important to get complete shifting of the trans without the shift lever hitting anything that limits its travel.  I'm convinced that's why my old trans died in the first place.  See ​ Shift Lever throw solution
 

Steve Bogert / Bonnie Sprague
"Wild Spirit"
1995 Catalina 36 Mk II, Tall Rig, Fin Keel, Hull #1412
Bellingham, WA

McFly
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Posts: 200

Steve, thanks for the post, hugely helpful.  Although your extender piece is a DIY work of art, I think my arrangement for how the cable attaches is slightly different than yours.  I saw your comment in your other post about re-indexing.  That was fairly easy to do.  I loosened the bracket attached to the shift axel and rotated the bracket a few degrees FORWARD.  The mental gymnastics shows that rotating this bracket fwd on the axel provides a more fwd attachement point which in turn brings the shift lever at the helm to a more AFT neutral point.  Mine still hits the pedestal, so I think I am going to try moving it a few more degrees ahead.  I also changed to the UPPER mounting hole for the cable connection, hoping the additional moment arm may help.  When you look at the attached pic, you can see that I made a red line denoting the original alignment of the bracket on the axel, allowing me to keep track of how much I rotated it.  There has been a marked improvement in my transmission's reliability when shifting into fwd due to the several ATF changes along with the addition of Sea Foam addivitve for about 45 mins (more details on that above within this thread).  

I would like to get through this season and then consider replacing the transmission in the fall just before haul out.  How did you deal with the geometry changes on the ZF 15M?  Did the 1/2" longer require removal of the shaft and taking a 1/2" off?   Or, can that 1/2" be accomodated by just sliding the excess out beyond the strut?  There must be guidance on how long the shaft can extend beyond the strut.  What about the height difference?  1/2" difference in drop seems like it could cause all kinds of alignment issues.  How did you overcome this?  

Thanks again for all the insights.

Mike 

Jackfish Girl, 1999, C36 MKII, Tall Rig, Wing Keel, In-mast furling, Monument Beach, Bourne, MA

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BHamster
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Posts: 19

Mike, 
Making the ZF-15 fit when I upgraded last fall wasn't that hard. 

  1. To accommodate the extra 1/2 inch length, I just slid the shaft back by that amount.  I'd heard that this might cause vibration problems, but I decided to just try it and see.  I was planning a re-prop this spring anyway and figured I could shorten the shaft then if needed.  I was pleasantly surprised to find that there was no increase in vibration.  In fact, I think that upgrading the transmission and replacing the worn damper plate may have reduced the vibration a bit. In any case, I don't have a vibration problem.  Since things were working well, I did not bother to shorten the shaft when I re-propped this spring.   
  2. To accommodate the extra 1/2 inch in height, I made some 1/4 inch flat shim plates and placed 2 under each engine mount. I also replaced the mount anchor bolts with 1/2 inch longer bolts. This raised the engine 1/2 inch and shaft alignment was close to perfect.  I still had to go through the tedious process of adjusting the engine mounts for perfect alignment at the coupler, but it wasn't too bad.  I think the only other change needed was to make the exhaust hose between the mixing elbow and muffler 1/2 inch longer. 

It was definitely a project, but I'm very happy with the result.  Good luck with whatever you decide to do. 
Steve 

Steve Bogert / Bonnie Sprague
"Wild Spirit"
1995 Catalina 36 Mk II, Tall Rig, Fin Keel, Hull #1412
Bellingham, WA

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