Transmission in Reverse - almost no revs

Hello All,

This seems to be a different issue than my recent post about the slight leak of transmission fluid from my Hurth 150V transmission.

Over the last two weekends, when I put the transmission into reverse when the engine is at idle rpms (about 800 rmp) the engine sounds as though it may stall, and when I throttle up to get some power/thrust the engine barely climbs to 1000 rpm no matter how far forward I push the throttle. I do get some reverse thrust, but it is weak.
But, the problem is not consistent... sometimes it seems fine, other times the above happens.

1) I put my GoPro camera under the boat to look for an entaglement... best I could see as it is a bit murkey, is the prop and shaft are clear.

2) transmission fluid is at the correct level.

I havent had a chance to look at the couplings while in reverse.

Could this be an alignment problem?
When I had a fuel pump issue in July, I also had the mechanic re-stuff the stuffing box. At that time he said that the propshaft appeared to be slightly misaligned. I was a bit surprised at this because in the Spring of 2016 when the prop shaft was replaced, the yard had to remove the strut that houses the cutlass bearing, reglass the hull, and reattach the strut to get the correct alignment because they said the alignment was too far out of adjustment to do it from the transmission end...

Could it just be a bad cutlass bearing? That too was replaced in Spring 16.

Or does this sound like a transmission failure?

Forward gear seems to be working fine.

Thoughts on how to narrow this down?

Thank you,
Peter Grabow
S/V CAKE WALK III
1987 30 Ultra 430
Jersey City, NJ
Liberty Landing Marina

Do you have a fixed prop??

Joe Valinoti
S/V IL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA

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Hi Joe,

Sorry, forgot that detail...

I have a 3 blade feathering prop, not a fixed prop.

Peter

I'd be looking at the prop for a problem. Can't believe it's an alignment issue. I'm assuming that in neutral everything is normal as far as engine RPMs??

Joe

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Hi Peter, is it a Kiwi prop. If so the pitch in reverse is much higher than in forward and can load up the engine.

Rob Powers
Respite 26C #50

Hi,

Joe - your input to being more of a prop issue than alignment makes sense as it doesnt seem to be a problem in forward...
And yes, in neutral all is normal.

Rob - yes, a Kiwi prop. When I had a short haul this Spring, I wasnt able to remove the screws on each blade to allow me to lubricate the blades. I was able to lubricate the hub, but due to time constraints and the fact that the blades were moving freely at that time, I let it go. Perhaps the lack of fresh grease has caught up w me and the blades arent reversing when the transmission goes into reverse.

I will see if I can get some video of the blades in/not in action...

Again, thank you for the comments. Additional thoughts, input, is of course welcome!

Peter Grabow
S/V CAKE WALK III
30U 1987 430
Jersey City NJ
Liberty Landing Marina

Hi All -

Following up on my earlier post from October - apparently all advice pointing toward the low revs being a prop issue rather than a transmission issue was good advice - again, I thank everyone for their input.

I put my Go-Pro camera under the boat, and though I didn’t get a very clear image/video, there appeared to be a bit of growth on the hub which may have been interfering with one or more of the blades going into the correct reverse position.
For the last few sails of the season, if I rev’ed the engine slightly before putting the transmission into reverse, the reverse thrust didn’t seem to falter as often. The increased force of the faster spinning prop shaft may have had the blade(s) clear off some of the growth from the hub, or push past it.

When I haul out for my Spring bottom cleaning I will be able to check the prop up close, clear any debris, and re-coat the blades/hub with bottom paint (I may have forgotten to do the hub last Spring…)

Another issued has popped up, but I will begin a new email for that one so as not to have multiple issues on a single thread.

Best regards,

Peter Grabow
S/V CAKE WALK III

30U 1987 430
Jersey City NJ
Liberty Landing Marina

Hello All -

This is a follow-up on the thread I began in October of 2018, regarding an issue with reverse gear on my Hurth 150V-Drive transmission.
I never hauled-out in the Spring of 2019, so getting a relaxed look (while not holding my breath) at the prop didn’t happen. I did, on a couple of occasions during the 2019 season, go under the boat to clean the prop, propshaft, hull, rudder, etc.
The cleanings made no difference in the problem I had been experiencing with putting the transmission in reverse, where it would either work, or give me only about 1000 rpm and little thrust.
If fact, toward the end of 2019, the problem got worse. A third variation arose - at times shifting into reverse would stall the engine completely. This became a bit unnerving when backing out of my slip - very tight quarters and if the wind was blowing… Oy!

So - this past Tuesday we pulled the transmission to get it rebuilt. Surprisingly, the VDrive came out without too much struggle. We did this with the boat in the water. Took about an hour and a half. Biggest issues were getting the prop shaft to slide aft enough to remove the trans, but it went - pulling it back into place may be another story, without being able to push it from outside… we’ll see.
Only one bolt broke off, and will have to be drilled out prior to the reinstall. Heat, PB Blaster (with tapping), time, etc… nothing worked.

Took the trans to the rebuild shop and after the owner/mechanic opened the trans, he said it was in worse condition than we had originally thought it might be… When removed from the engine, it was obvious that the driveshaft splines were worn/slightly twisted - not good. I haven’t seen the internal pieces yet, but not just the reverse gear was worn. But after 34 seasons, I am not surprised. Surprisingly, the damper plate appeared to be in very good shape, no play in the center spindle and the splines there looked good, though there was some slight movement and shininess on some of the springs… Since the driveshaft showed signs of wear, I decided that we may as well put in a new damper plate while there was easy access to it.
Would hate to reassemble, and then have a chatter or some other issue caused by unseen problems in the original damper plate.

With the trans out of the way, took the opportunity to tighten the oil-pan bolts, engine mount riser bolts, clean-out/and replace the gaskets on the heat exchanger, clean, undercoat and then paint most sections that needed refreshing. Here’s a link to some photos:
https://www.dropbox.com/sh/vzuaaeyy989mvp9/AABeZRT6op_aR8aDNt0ulkDja?dl=0

I shot video of pretty much the entire process, but it needs to be edited before posting (that may take a while!).

Will post more after the reinstall… fingers crossed!

Peter Grabow
S/V CAKE WALK III
1987 30 Ultra 430
Jersey City, NJ

Peter, I rebuilt my own gear last year in the water. I made a tool for pulling the shaft back up. It is just a piece of pipe that fits over the shaft and still fits through the hole in the vee drive. One inch schedule 40 as I remember.
I drilled and tapped for a set screw in one end to grip the shaft and drilled a half inch hole right through the pipe for a half inch bar pulling / twisting handle.
It worked great. You may have to loosen and re-set the grip point so it doesn't end up covered inside the gear but it will make quick work of the job.

Paul M
NS30U #211, Sandpiper
Cowichan Bay, B.C.

Hi Paul,

That sounds brilliant! Do you have a photo or sketch of the tool you made from the schedule 40 pipe?
How long is the piece of pipe you made into the 'puller'?

I have pieces of leftover schedule 40 pvc pipe laying around after building my winter cover frame. If I can make this work it would be great!

Thanks,
Peter

I’m not sure PVC would be strong enough but you could try it I guess. I just used a piece of steel pipe I had around, about two and a half feet.

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Many thanks Paul!
The images are very helpful. Not sure if I can locate some steel pipe, but hoping if I don’t apply too much torque the pvc might do the job.

Will advise after the reinstall…

Best regards,
Peter

Peter: Lowes and Home depot sell various pipe sizes and lengths.

Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA

Thank yo Joe!
I have a couple of Home Depots right near me. Makes that easy!

Peter
Grabow
S/V CAKE WALK III
1987 30 Ultra 430
Jersey City, NJ

Take some calipers.

Paul M

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Thanks Paul.

Ok - so the trans was completely rebuilt - was in worse condition than expected. Reinstalled - was able to pull the propshaft back thru the trans with not much effort, without any sort of ‘puller’.
Got it all set up, connected so the ‘throw’ was putting the trans either fully into forward or reverse. Prophaft seems well aligned coming out of stuffing box. Took it for a run, and boat seems quieter when motoring.

But this didn’t fix the problem I was having with reverse - the problem still persists… either only 1000 rpm, or it stalls the engine, or it works fine…
Forward gear is not an issue.

So - I am thinking the problem is either an issue with my Kiwi Feathering Prop (though I have cleaned it as best I can when under the boat recently, and the blades move freely when moved by hand.
Or, perhaps an issue with the cutlass bearing? Maybe part of it has worked loose and it binds on the prop shaft??? The cutlass bearing was replaced in Spring of 2016, and issue began in summer of '18.

I will be hauling out in then next couple of weeks and will be able to get a good look at propshaft, strut/cutlass bearing, and prop…

Thoughts???

Thank you,
Peter Grabow
S/V CAKE WALK III
1987 30 Ultra 430
Jersey City, NJ

Hi Peter, here’s a quote from Kiwi Prop’s website.

UNIT LUBRICATION:

By far the most common cause of reverse overload is a lack of lubrication inside the Kiwiprop. This can be in the boss of the unit and or on the individual blades of the unit which must be free to move easily about their mounting pin at all times.

This assumes there is no binding caused by external fouling - e.g. Barnacles or antifouling.

Could this be your problem?

Ron

Ron & Diane Schryver

“Alpha Waves” 1987 NS30U #393

Georgian Bay Midland ON

Hi Ron,

Thank you for the post from the Kiwi website. Lack of grease of the prop is what I am hoping is the issue. I have previously thought that this might be the issue but when the blades turn easily enough (again this past weekend) by hand when I am under the boat, I second guess this as being the problem…

However, in the Spring of 2018, on 2 of the 3 blades, the screws that are removed from the blades to insert grease sheared off. So I was only able to grease one blade and the central hub. The problem started in the Fall of 2018.
I was not able to haul the boat in 2019, and will finally haul her out in a week or two, and which point I can drill new grease holes in the blades and insert the new screws received from Kiwi. I will also be able to thoroughly clean each blade, the hub, grease all points, etc.
Hoping that this prolonged lack of fresh grease just enough to bog down the reverse action.

Or… if it is the cutlass bearing, I will then probably need to invest some more money in a local mechanic to replace the bearing.

Peter

Hello All -

I hauled out last week, had the bottom powerwashed, cleaned & waxed the hull, sanded the bottom and put on two new coats of ablative paint, and inspected the prop and cutlass bearing for possible causes to the reverse issue:

Ron - Lubrication (or lack thereof) seemed to be a good part of the issue.

First, I removed all of the blades, though one at a time, so they went back onto the arm from which it came so the pitch settings stayed intact. Removed all of the old grease out of the blade ‘sockets’ and off of the arms. I knew I had to replace one of the grease-point screws on one of the blades as the head sheared off 2 years ago (Kiwi sent me new stainless replacement screws last year), so I drilled the new grease-point hole and made sure all of the fibers were cleaned out.
After reinstalling and greasing all of the blades, it seemed that at certain times when hand moving the blades, two of the blades ever so slightly got hung up on the roller-stops. Carefully aligning the stops (which are rounded triangles that freely turn) I found that at certain alignments the notch of the blades would catch a triangle point on the stop instead of passing by it as it is supposed to going into reverse… mostly because of some fouling that remained on the notch of the blade and on the roller-stop. If the opposing blade had already hit the stop it prevented it from spinning out of the way and kept the blade going into reverse caught on the roller-stop point.
Ah ha!
So this must have left 1 or 2 blades in forward, or halfway to reverse, and only 1 blade going into reverse thereby overloading the engine causing the low revs, or stalling.

After this discovery I made sure the roller-stops and the notch on each blade was completely clean, and then I filed the notches slightly to make sure they had adequate clearance to pass over the roller-stops.

I then pumped grease into the 2 access points on the hub… the main section took so much grease that I had to stop and check my grease-gun to see if I had run out of grease! Once all was adequately cleaned and greased I was fairly certain (though not 100%) that the reverse issue may have been solved.

After inspecting the cutlass bearing carefully it was determined to be in working order.

Replaced the shaft zincs. cleaned the prop shaft and as far up into the hull as I could reach.

Waited for the tropical storm to pass (hope everyone on the East Coast came through the storm with no or very minimal damage…) and launched on Wednesday afternoon.

While tied to the dock I tried reverse multiple times - it works fine!!! Tried it again later when in the bay - it still works!!! Tried it again when in NY Harbor before going in to dock… we are back in business!!!

So apparently the real issue was the prop… though I spent several ‘boat bucks’ rebuilding the transmission trying to solve the issue, I am actually glad I did as the condition of the transmission was probably going to cause a problem sooner than later, and it is now done.

Again, thank you everyone for your input, thoughts, advise/suggestions…

Peter Grabow
S/V CAKE WALK III
1987 30 Ultra 430
Jersey City, NJ