Yanmar SD50 Oil Seal Replacement

"Hi, I have an SD50, three yea

"Hi, I have an SD50, three years old and the oil in the sail drive gear box has started to allow water in and the oil emulsifies as soon as the gearbox is used (following new oil).

I believe the oil seal needs replacing and I purchased one and asked the local dealer to fit it for me. I explained that they will need the right tool to extract the shaft assembly and initially they said they didn't want to do the work because "they might break the casing". I couldn't find anyone to do this work so ended up putting the boat back in the water and the leak continued.

It now seams worse so I must get the work done. I asked the dealer again if they would do the work and eventually they reluctantly said they would try and this work is scheduled for 28th April and it will cost me more money to have the boat lifted again.

The purpose of my email is to seek proper expert advice on the best way to help the dealer get the shaft assembly off without damaging the drive leg because to replace it will cost £4000 (about $6000). I have spoken to Barrus but they weren't really able to help except to say that the dealer should do the work. I believe that a slide hammer is needed but the dealer hasn't convinced me that they have the right tool or that they will be sucessful. Can anyone advise please?

The engine leg did suffer some corrsion pitting because of a poor quality marina but the shaft assembly area looks ok but the whole casing has been painted over with epoxy paint meaning that I shall need to chip away at the joint between the assembly and the casing otherwise it won't help the extraction. I have the SD50 service manual but it doesn't provide good information.

Is there anything you can tell me that will help please? Any special tool I should try and locate? Any special tricks to getting at the oil seal?

I really hope you can help as I fear my SD50 will be damaged and my sailing for 2009 over as I can't afford a new leg.

Sorry to be a nuisance but I really hope you can help.

Des Owen"

"Hi Des, Contact Yanmar head o

"Hi Des, Contact Yanmar head office and ask for assistance and they will guide you. At times you will get electrolisis in the marina due to bad grounding of their electrical and other vessels near you. It is neccessary to change zincs on the drive at regular times, it may be every 3 months depending where you are moored. I would change slips. There is a kit you can clamp to the engine and throw a large zinc overboard. Also a meter you can install to tell you of electrolisis. You may not need a complete new drive but only a housing. It may come as a lower assembly if memory serves me right. Check and know your options. It may be neccessary to have the boat on the "hard" untill you can afford proper repairs. Good luck. Regards Ron"

"Thanks Ron

I've just c

"Thanks Ron

I've just contacted the Yanmar head office and await a reply. I actually left the marina last season and took a floating pontoon morring in the harbour - about quarter the cost and must nicer and the boat always floats - since then, hardly any erosion of the zinc.

So I think my only current worry is getting this job done. I did get compensation from the marina but not enough to cover the cost of the replacement leg. I've looked into just getting the casing replaced but the dealer seems a bit shy on that option.

Will post when any developments in case this affects / helps others.

Many thanks, Des"

"Hello Des, It may be time to

"Hello Des, It may be time to find another service facility for a second opinion. It does sound as if lack the experience to do SD work. Then again they are the hands on people, and I am here on line. I have seen electrolisis eat up many a drive leg. It is a expensive lesson but a valuable one. I look forward to your comments after your audience with Yanmar. I always have found them abiding. I wish you well. Best regards. Ron"