V-Drive Issue?

[HUMPH]

I am looking for some recommendations before I have a mechanic check out this issue. I picked up a comforter on my port prop (yes a comforter, twin size) a couple of years ago. I had a diver remove it and noticed difference in performance from the starboard side so I had the props pulled and had them propscanned. They saw that some of the cup was reduced on the port side but I had them both revised close to what Dom had recommended. I noticed a whine coming from the port side but now it seems more noticeable. The question is would this be from a cutlass bearing, the transmission or some other item TBD. I have changed the transmission fluid since this event and it looked perfect. As always, any and all help is appreciated.

 

[fwebster]

First, it isn't the cutlass bearing. They are rubber sleeves in bronze tubes so if one wears or gets deformed, the rubber wears away prematurely. The resulting sound is a rumble as the shaft chatters in the loose rubber bearing.

Some Hurth 800-HSW/ZF80-IV transmissions have a whine in the side that runs in reverse (while in forward), but that usually is diminished when you put the transmission in reverse. These transmissions are petty robust, so it is unlikely that the comforter caused a problem. Sometimes when you solidly ground a boat and the props contact the bottom, you can even stall the engine to the point where it dies without damaging the transmission. My approach would be to not fix anything until you know for sure that something is broken.....keep an eye on the transmission, change the fluid annually and have a fluid analysis done......and look for ferrous metals in the sample. A high ferrous metal result usually means bearings, shafts, thrust washers or gears wearing, and that indicates that you have a serious problem in your future.

 

[HUMPH]

Thanks Frank. The whine didn't start until my bedding incident, that's why I am concerned it did some damage. I am just not as familiar with these transmissions as I should be. I think I'll change the fluid a bit early since I have a few more trips left this year and don't want to cause more trouble for myself.

 

[peterkvs]

Ken,

I just changed my cutless bearings. What I was hearing was a squeal after I took the motor out of gear and the props and shafts were coming to a stop. I could not hear this noise in the engine compartment, only in the cockpit with the engine hatch closed. They did not make any noise while I was in gear, only after I took them out of gear. Both cutless bearings squealed, both squealed after coming out of either forward and reverse, and BOTH started making the squealing noise on the same day at the same time after leaving a fuel dock. When I pulled the boat to have them replace it took almost all the strength I had to turn the prop holding the ends of the blades. After replacing them I can turn the props with one hand on the SHAFT. There is no longer any squealing. The cutless bearings were obviously dried up and swollen. I always wondered if the bearings got contaminated with oil or fuel or something at the fuel dock that caused them to swell and start squealing. Try turning your prop shaft by hand down where the V-drive connects to the prop shaft. Maybe it will give you another clue as to what is going on. See if the port and starboard feel the same and take the same force to turn.

Good Luck,

Pete

 

[carterchapman]

Ken,

I know you said your port side whine started up after the comforter issue, but my port side has always whined in the 1200-1700 rpm range...I need to check what Frank said about reverse on mine...

 

[HUMPH]

Ken,

I know you said your port side whine started up after the comforter issue, but my port side has always whined in the 1200-1700 rpm range...I need to check what Frank said about reverse on mine...

Thanks Carter. Mine starts whining much like my employees, starts early and keeps going until going fast.

 

[rcknecht]

I had a cutlass bearing go on a prior boat, and it looked like a blown up cigar. My strut was bent causing the bearing to wear out. I did not notice a whine. If you pull your boat, inspect the bearing, turning the prop. It should be easy to turn (in neutral) without a lot of play in the shaft. The bearing should not pertrude from the strut.

 

[Sea Gull]

Ken, have you considered prop singing? I'm not sure from your original post if this started immediately after the comforter or not until the props were re worked. If the whine started after the props were tuned and this happens only at low speed, it may be prop singing.

 

[HUMPH]

Nope, whining started right after I made the bed and seems to be getting worse. I didn't do the propscan for several months after the diver changed my sheets. BTW, thanks again for the tour of your boat in AC. Love the mid master.

 

[HUMPH]

Update. The transmission has a definite clunk when I shift and according to the troubleshooting guide, the clutches may be shot. Could picking up a comforter while in reverse (with a little throttle) damage the clutches? I think it's time to have a qualified service tech ride with me to diagnose the problem. I checked the fluid level again this morning and it was fine. There was no problems until that f'ing comforter has been an expensive little bugger...

I assume that if the clutches (or bearing, etc.) needs to be replaced, the engine needs to be disconnected, moved aft and the tranny removed? Sounds like a couple of boat units to me......!!!!!!

 

[MasterFab]

Ken,

I wasn't there for the comforter incident, nor have I heard the "clunk", so I'll attach that disclaimer, but clutches typically fail due to slippage. That slippage can be induced by a variety of factors - wrong fluid, low fluid level which leads to foaming of the fluid and a loss of line pressure, or just normal wear over time. Once they start to slip, they may warp due to frictional heating, but that doesn't lead to a clunk. Instead, it often results in a loss of a clean neutral, since the plates and friction discs can no longer freewheel with a little bit of space between them.

I am not saying it's not possible - anything is possible depending on how it is broken or failing, but the fluid between the discs acts as a cushion during engagement, so the clunk coming from the clutches themselves just doesn't seem like it's the problem. Have you gotten any results from an oil analysis since this started? Those results could be helpful. Have you looked at the filter on this transmission? Debris in the screen could also point a finger.

My guess would be a bearing or gear failure, with the bearing more likely. It's also possible the failure is outside the transmission, and the coupler is to blame. But, unfortunately, either way, the engine and trans have to be separated. Having an experienced technician come along for a ride is a good idea.

Dale

 

[fwebster]

Do you have Hurth 800HSW-IV or ZF-80-IV gears?

There is a design issue with the intermediate shaft on the 800-V1's and a number of transmissions have failed as a result. It is my belief (I replaced the entire transmission rather than rebuild and just never got around to disassembling the gear box) that something happens to the thrust washers/spacers that allows the shaft to move forward/reverse as torque is applied. The failure begins as a whine then gradually turns into a growl and finally you hear all kids of rattling and clunking going on as the bearing rollers begin to disintegrate and allow even more movement. This failure is almost always on t he port side in a V-drive boat.

The quickest way to either rule in or rule out bearings, shafting, or gear failure is to remove the filter screen immediately after running the boat in neutral for several minutes, then wash the filter in mineral spirits and retain all the mineral spirits that the filter was washed in. Now, pass a clean magnet thru the wash solvent. If you have bearing/shaft/gear problems there will be a lot of ferrous metal particles adhering to the magnet. With a good mechanical stethoscope, an experienced transmission guy should be able to identify where the noise is coming from.

Also, Caterpillar engines use a vulcanized coupler assembly. I've never seen one fail and if one did fail, these engines have so much torque that they wouldn't partially fail.......the 2 parts of the fly wheel would separate and you would be dead in the water on that side.

Get a mechanic involved before you lose sleep over how to get the transmission out......if it comes to that, ask. I've had to do it.

 

[HUMPH]

I have the ZF-80-IV. A bearing sounds more likely at this point but that is still a major repair I imagine. I have never worked on transmissions so this would be done by a professional. I will try the filter screen trick (and take samples), thanks guys.

 

[fwebster]

The problem with letting this go is that if you do have a bearing failure going on, then the bearing is sluffing off metal particles and they are being circulated through out the transmission. It is very difficult to get the particles out of all the valve bodies, passages, etc. and that could lead to another issue requiring another transmission removal later. Sooner is better than later in this case.

Also this repair isn't one for your typical dealer mechanic.......oh wait, do you have a dealer yet?. If it is the usual ZF bearing failure, somebody who has experience in setting up the clearances in ZF gears needs to do the work.

Good luck with it...........

 

[MasterFab]

Ken,

What Frank said. I've built a few of these, and it's not for the timid. The mechanic needs to have familiarity with precision measuring equipment, dial indicators, etc. And when building one of these, cleanliness is the word of the day. You can't do one of these on a wooden workbench in the back of an open shop. At least, you shouldn't. I have a 16 foot long stainless steel topped bench for jobs like this, and I clean it with solvents, followed by Windex and paper towels, before I lay down the first part. Every part has to go through a wash tank, followed by cleaning and drying with compressed air.

I have found that it's often just not worth it, depending on the level of damage. By the time you pay for parts, labor, etc. you're better off just buying a new one. Most of the time, you get trapped in the "well, while we're here" syndrome, and you're replacing ALL the bearings, races, clutch packs, seals, etc. Price it both ways, and make your decision, but the peace of mind from a new one is hard to beat. This isn't a job you want to do twice!

Frank - question. I was speaking to a friend of mine, who owns a Sportfish with a pair of 3116 Cats. He had both engines out last year, and was told he needed to replace the damper plates. So, he found an online supplier, and the plates he received were for 3116 Cats, but they were not like the originals - thinner metal, and made with springs, not vulcanized rubber. They did appear to fit. But, the CAT mechanic saw them, and recommended not using them, due to the prodigious torque output of the 3116 Cats. So, he wound up buying the Cat plates, at twice the price. Have you ever had experience with the aftermarket plates?

Dale

 

[peterkvs]

When looking for ferrous metals versus not ferrous metals I do the following.

1) Wash the filter with an appropriate solvent. You can either put Clean Mineral Sprits in a clean glass container and agitate the filter in the container, then pour the contents of the container through a coffee filter catching all the contaminates, or what I like better is to put a coffee filter in a funnel and spray the filter with brake parts cleaner letting the brake parts cleaner funnel through the coffee filter and let the filter contain the contaminates.

2) Then, take a magnet and hold it on the clean (downstream) side of the filter and move it around. Only the ferrous parts will move with the magnet and the non ferrous parts will not.

Both times I have washed my filters into the funnel I have never seen even a single spec of contaminate.

Get two oil sampling kits and the tool from Cat and take samples of both side and send in and compare.

Good Luck,

Pete

 

[fwebster]

My experience with Caterpillar is that they design engines and equipment to last and to not have parts failures. That means every part is engineered to exceed the minimum requirements for a job. I never use anything but Cat OEM parts....period. On something like the damper plates where you you pretty much have to tear the boat apart just to see them, there is no way on earth I'd use aftermarket parts. Additionally, a damper/couple made with a spring assembly may be on for a truck or a road grader, but on a boat where you dump all the load on at once, instead of dampening the shock via a clutch assy or a shuttle, a vulcanized damper is a far better choice.....which is why Cat chose that approach.

Your friend made the right choice.

 

[MasterFab]

I agree - he's had no trouble since the repair.

Dale

 

[barlow]

Follow Franks advice and replace with a new transmission, PERIOD as you say in the US. The cost of all the replacement parts/labour makes a rebuild uneconomic. Just my personal experience.

 

[HUMPH]

Follow Franks advice and replace with a new transmission, PERIOD as you say in the US. The cost of all the replacement parts/labour makes a rebuild uneconomic. Just my personal experience.

Well that would be a bit extreme if it just needs a bearing right?