dismantling bukh sail drive leg

[actionoptics]

Found water in the gear box and leg of my Bukh 24 SME.
I have taken off the propellor and anode and rope stripper; removed the two large bolts
from the end casting but can't get the casting off.
I have assumed the whole lot would come out, i.e. the casting, the prop shaft and seals but do I have to
undo what looks like a lock ring around the prop shaft to get the casting off and then
pull out the shaft and seals?

I've not tried posting a photo before so hope this works.

http://www.actionoptics.co.uk/leg b.JPG

 

[VicS]

I'm not sure what bit you think is a lock ring

but having removed the two bolts Id expect the casting carrying the bearings and seals to be removeable ... although not easily. There is probably an O ring between it and the main casing that is firmly stuck

Try tapping against the lugs where the bolts go with a hammer and a block of wood to try to turn it and free it. gently one way then gently the other.
Maybe some release oil will help. (eg Plus gas)
Maybe some boiling water over the casing will help.

Got a parts diagram anywhere ??

It might be possible to renew the seals without dismantling but need a manual or at least a diagram to tell. May just need to remove what you think is the lock ring

 

[actionoptics]

Bukh leg

Thanks for the reply.

http://www.bluemoment.com/manuals/DV10-24.pdf is the diagram of the leg from the owners manual.
I did knock the casting round an inch and hit the lugs but the gap did not get any bigger. Maybe I was too cautious.
The link in my post is to a temporary page on my web site showing how far I have got so far. The ring is the one
on the shaft immediately in front of the casting. It has four cut outs which I guess is for a special tool to undo it but I can use somethign like an alluminium rod to knock it round without damage.

 

[mcalan]

I have recently been through the same problem (see my posting) You are right once the prop is off and the two allen type bolts holding the anode ring are removed you need to tap where the lug of the anode ring meets the casting of the sail drive leg. There is a large o ring which seals the crown wheel /shaft.
Once removed there is a ring on the shaft with a cut out in it which you can tap until it starts to undo.There are then two seals on the shaft which are mounted opposed to each other.The inner one keeps the oil in and the outer water out. Incidentally I found mine were fitted incorrectly. I also as a precaution flushed the leg out with flushing oil to make sure I got rid of as much of the water as I could. I do have a handbook but its in hard copy I could try and photograph it if it helps ? Let me know how you get on as Id be interested to know

Alan

 

[actionoptics]

Thankyou Alan.
I have just got back from my boat and I have sucessfully removed the lock ring which gave access to the seals.
I did not have to remove the casting !
Obviously damaged the seals getting them out but I already have new ones, but what also came out was the
quite heavy, thick metal sleeve with an O ring at its inner surface. The seals have been running round this and
it is scored so no wonder the water got in.
I'll have to buy a replacement from BUKH tomorrow.
I had already drained out the old watery oil and then flushed thoroughly and drained again.
I found that the drain plug had been fitted with an O ring instead of the correct gasket so I'll
replace that.
The seals only seem to last about 400 hours motoring but I will engage the gear box in future
when sailing as a free wheeling prop must be causing the seals to wear.

 

[mcalan]

Well done Im surprised to hear they only last 400 hours! where did you glean that pearl of wisdom from?

Just as a matter of interest which way were the old seals fitted? As I said mine were wrong. I am going back in the water at the end of the month an have my fingers crossed that all will be ok this time!

Alan

 

[actionoptics]

Had to have new seals fitted when I bought the boat in 2006. Actually the job was done by Bucklers Hard Boat Builders (June 2006) and they only fitted one new seal and left the original two in place. This one new seal only lasted two seasons (about 350 hours) and failed (June 2008) as I was half way across Lyme Bay when I found watery oil frothing out of the dip stick hole. Had to sail back to Lyme Regis as the wind and tide dictated that direction. The engineer found the three seals were all shot as was the sleeve. He fitted two new seals and a sleeve. I have just taken them out and seen that they were the correct way in - back to back with the springs facing the liquid. I have checked my Log Books and those new seals lasted about 540 hours so my original guess was a bit out.
Have to say that the Harbour Master; his assistant and Jess at Lyme Regis; Jess's parents and the members of the Sailing Club could not have been more friendly and helpful.

 

[mcalan]

Ah I see. I think the sleeve is not an original part and may have been put in at some stage if the original shaft was worn?. I only have two which sit on the shaft. When I was worried it was worn it was suggested that a sleeve was put on. must remember to keep a note of hours run to see how it compares
thanks

Alan