SD50 Cone Clutch Lapping

[arsenelupiga]

Originally Posted by geoleo

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

so, how is life in peanut gallery ?

[geoleo]

Originally Posted by arsenelupiga

so, how is life in peanut gallery ?

Its great -we are throwing peanuts to the Aussie monkeys who are begging-but they seam to be drunk again and cant stand up.

[arsenelupiga]

Originally Posted by geoleo

Its great -we are throwing peanuts to the Aussie monkeys who are begging-but they seam to be drunk again and cant stand up.

So, what alternatives do you have for SD 50 or SD 60 misery I have to put up with ?

[geoleo]

Sorry but I do not know of any. I did think that that owner of the 50ft cat Sulliere had it straightened out but I am not sure. In the meantime I have been consulting a friend who is trying to buy a big cat to avoid these Yanmars due to these problems and advising Catanas with Volvos of all engines. They had a total recall of their SD 40s and provided new engines!! Myself I always thought Yanmars were tops--- having had several in past 45 years. There must be some answers out there blowing in the winds. BTW - I love Australia and its peoples.

[arsenelupiga]

Originally Posted by geoleo

Sorry but I do not know of any. I did think that that owner of the 50ft cat Sulliere had it straightened out but I am not sure. In the meantime I have been consulting a friend who is trying to buy a big cat to avoid these Yanmars due to these problems and advising Catanas with Volvos of all engines. They had a total recall of their SD 40s and provided new engines!! Myself I always thought Yanmars were tops--- having had several in past 45 years. There must be some answers out there blowing in the winds. BTW - I love Australia and its peoples.

problem is not bad once you know what to do and have tool. Mainly all european boats will come with these.

My technical side actually thinking this is good solution. Just imagine getting rope on propeller and slipping clutch will prevent pulling engine out of hull. In saying that, I know of Lagoon 500 that sunk for exact that reason catching dinghy rope. I was unable to determine whether they had SD 50 or propshaft.

In Australia we have moneys only in zoos. Feel free to take peanuts and go to Sydney Zoo. Just make sure animal activists do not see you.

We get these boys that you can practice without fear of animal activist coming around

[ChrisseH]

Referring to several other threads on the SD40/50 slipping cone problem, I think the main reason for the slipping is/was Yanmar's original gear lube specification. I know it sounds ridiculous that such a large marine engine manufacturer makes such an error, but the fact is that Yanmar is not the original manufacturer of these sail drives. If you have brass parts in a gear box (or a clutch) you should never use GL-5 rated gear lube. GL-5 rated oil has superior lubrication properties, which is good for the gears and bearings, but it generates excess corrosion on the clutch cone which is of brass or a similar kind of copper containing metal. I have recently only used GL-4 rated gear lube in my SD50 and I have now (after the lapping) obtained more than 500 additional hours and there is still no tendency to slip. So my assumption is that most of the SD40/50 slipping cases could have been avoided simply by using only GL-4 rated oil. I have also heard that Yanmar later changed the gear lube specification. Note that the clutch cone in the SD50T version is of steel, so there GL-5 lube should be OK.

[UFO]

Originally Posted by ChrisseH

Referring to several other threads on the SD40/50 slipping cone problem, I think the main reason for the slipping is/was Yanmar's original gear lube specification. I know it sounds ridiculous that such a large marine engine manufacturer makes such an error, but the fact is that Yanmar is not the original manufacturer of these sail drives. If you have brass parts in a gear box (or a clutch) you should never use GL-5 rated gear lube. GL-5 rated oil has superior lubrication properties, which is good for the gears and bearings, but it generates excess corrosion on the clutch cone which is of brass or a similar kind of copper containing metal. I have recently only used GL-4 rated gear lube in my SD50 and I have now (after the lapping) obtained more than 500 additional hours and there is still no tendency to slip. So my assumption is that most of the SD40/50 slipping cases could have been avoided simply by using only GL-4 rated oil. I have also heard that Yanmar later changed the gear lube specification. Note that the clutch cone in the SD50T version is of steel, so there GL-5 lube should be OK.

Yes I read those before I purchased the boat and have been running the correct oil, as was the previous owner - Although before him who knows.


I did recently read in the SD50 manual that Standard maintenance is to lap every 500 hours and to replace every 2000 hours - Sounds like a bit of a money spinner.

[UFO]

Anyone know where to get the Lapping compound - 280 Silicone Carbide in Australia?


Only found a 1KG tub so far or the Auto Stores only have in Fine Medium or Coarse - Not sure which of those would be the correct one as there is not Grit rating on them.

[ChrisseH]

I bought a small set with two lapping pastes intended for valve lapping from a shop for auto parts and used the paste that was closest to grain size 280. I think the grain size in my case was 320.