SD50 Cone Clutch Lapping

[UFO]

Just a quickie...


Roughly how many hours to pull the cone clutch (SD50) Lap and replace including checking back lash etc. Access is easy with LOTS of room, but still in the water.



Just had a quote from someone charging like a wounded bull and having watched a Youtube video from an earlier thread which did not take very long (I will probably do myself now) I wanted to get an idea of how many hours are involved in the process.


Thanks in Advance

[ChrisseH]

It depends very much on how handy you are and what tools and spares you have available. An experienced Yanmar service guy would do it in 4...6 hours, but for me (doing it for the first time) it took almost three days of active work. Actually, as the boat was on the hard, it took me all together almost a month, as I ordered spare parts an did other repair work in between. So for me it took approximately one day to remove the clutch assy, one day to disassemble the clutch, lap the cone surfaces and to rebuild the it again. Then it took maybe 3...4 hours to reinstall the clutch assy back to the sail drive. As spare parts you will need at least the left-handed nut on top of the clutch assy, lapping paste and (depending on how worn they are) new bronze washers. You might also need new shims if your drive unit is very worn. Changing or adding shims is not a trivial job as you might need to reassemble, test and open up the drive unit a few times before you get it right.

[lockie]

Corroded bolts might be one of your biggest time-wasters. Unless it all looks pristine, spray them a few times with one of the usual fluids, starting well in advance, then before you are ready to start give them all a try.

Cheers, Graeme

[arsenelupiga]

my experience with sd 50, you probably have more space than me.

getting out 30 min,
disassembly 60 min - best to have the tool for the top nut and vase.
lapping 30 min
assembly 60 min
put back in 30 min

do it slow and easy not to make mistake. take pics. you can reuse the top nut couple times, assuming you do not damage too much. I also have couple spares but not used yet.

I done once and is now good 300 hrs so far, so cant be that bad.

my nuts are not corroded and hours now getting towards 1200.

[Timreyn]

I did this job for the first time a couple of years back. I would agree that if you had experience you could probably do this in 6 hours. I am thinking I probably spent this the first day getting it apart and the same the next day putting it back together. I took a lot of time making sure I was doing everything right and took pictures so I didn't screw anything up. Next time for me I am guessing 6 hours, maybe 8. Still worth doing yourself. I don't intend to do it again until I notice some slippage.

[Aqualibrium]

Once you have done it a few times and get to know the potential problems it will be fairly quick. I’m down to about 1.5 hrs now.
Critical things are
1. Removing enough oil from gearbox to ensure you take level below selector
2. Clean threads on the 4 studs that you have to back the nuts off on. I ensure they are well covered with an anti seize compound
3 Measure the length of thread protruding from nuts before slackening nuts, this is to ensure when retightening and re engaging gears you get it right!
4. Having a splined holding tool to for the removed clutch assembly in a vise whilst loosening the left hand thread nut
5. 30 seconds of lapping is more than you need. Ensure you wash all lapping compound off both faces of the cones!
6 Take note of where the spacers are while disassembling and refit in same place.

It’s not a hard job once you have the right tools and the holding tool. I bought a 2 nd hand SD 50 from a Yanmar mechanic app $300 which I made the spline tool from and gave me a spare clutch pach for even quicker Change over!

If you don’t have the holding tool use a couple of bits of aluminium angle as soft jaws in the vise to protect the spline, not ideal but I used that several times satisfactorily before making up the holding tool.
Good luck it’s not hard!!!!

[pondering65]

I also paid to have one done and then in talking with mechanic who did it he said he had step y step instructions for this procedure.. I got his copy and guess what I did the other one myself. If you have access to a vise and these instructions its about a 4 hour job. Total cost was less than 10.00 for the paste needed to lap cones... If interested in these let me know and send me a PM. I will find the somewhat oil marked instructions, make a copy and email them to you.

[Moontide]

I would agree that it can be done in 4 hours. Having the right tools, including a 27mm socket, before you start is assumed. Also assuming no problem backing off the nuts and pushing the part into the bell housing.



The spline tool is handy to avoid damaging the shaft, but can protect splines with aluminum and even wood. Having a vise is almost mandatory to get the nut off.


How much was your mechanic quoting?
Has he ever done it before?


Bill

[pondering65]

I did not have a spline tool the step by step instructions stated to just use removed bolt to thread in top and then used a vise grip to pull sleeve up and out, which it did perfectly. Then I set it in a vise to disassemble, lap cones and reassemble. You will need the 27mm socket or wrench. Been working as good as the one I pd. mechanic to do !! - Got cat so 2 sd-50's unfortunately..

[UFO]

Originally Posted by Moontide

I would agree that it can be done in 4 hours. Having the right tools, including a 27mm socket, before you start is assumed. Also assuming no problem backing off the nuts and pushing the part into the bell housing.



The spline tool is handy to avoid damaging the shaft, but can protect splines with aluminum and even wood. Having a vise is almost mandatory to get the nut off.


How much was your mechanic quoting?
Has he ever done it before?


Bill

Yes hes done it before - Quoted Au$1390 in Labour (for 1 Drive) - Fortunately it was in an email and not to my face, so he could not see me ROFL.

[UFO]

Just trying to figure out what are the parts from the diagram that I should get, just in case needed.



67 is the Left Handed nut, but in a Video I have watched there was a single washer directly beneath this - So would that be Number 68 which is listed as a collar set?

[ChrisseH]

Originally Posted by UFO

Just trying to figure out what are the parts from the diagram that I should get, just in case needed.



67 is the Left Handed nut, but in a Video I have watched there was a single washer directly beneath this - So would that be Number 68 which is listed as a collar set?

Yes, these parts are correct. However, when I ordered part 68 I received just one bronze washer. Refer to the appended photo.

[ChrisseH]

Sorry, my picture was to large and I have no simple means to decrease the resolution in my phone. However the Yanmar spare part number is 196320-04410 for the washer and 196324-04380 for the left hand nut.

[UFO]

Originally Posted by ChrisseH

Sorry, my picture was to large and I have no simple means to decrease the resolution in my phone. However the Yanmar spare part number is 196320-04410 for the washer and 196324-04380 for the left hand nut.

Thanks

[geoleo]

Originally Posted by UFO

Just a quickie...


Roughly how many hours to pull the cone clutch (SD50) Lap and replace including checking back lash etc. Access is easy with LOTS of room, but still in the water.



Just had a quote from someone charging like a wounded bull and having watched a Youtube video from an earlier thread which did not take very long (I will probably do myself now) I wanted to get an idea of how many hours are involved in the process.


Thanks in Advance

Why should any sailor have to go thru such ridiculous agony to get his boat to work??????