First thing to do or check is the oil in the gearbox. Make sure it's the correct oil the maker stipulates.

Filippos said..
Hi Ramona! Thank you for your answer.
In our case the oil is the correct type but i believe it has not been changed in the last 300h of operation. You think changing the oil will have any effect in the slipping?

Do you really know it's the correct oil? Some boxes use transmission fluid oil, some engine oil and some single grade engine oil with no additives. I would suggest changing the oil to the exact specifications first and try that.
Search down a few pages on this forum and there will be a similar post on the same engine and saildrive.

Do as Chris says and identify the gear box then call the Bukh boys at Tarren Point and they should be able to tell you
everything you want to know.

There is a taper on dog gears coated in a substance that wears out allowing gear to slip forward and reverse are same dog gears are inter changeable so if forward is problem to get you out of trouble you can get forward lose reverse Bench test main shaft will seem perfect but not my engineer and self had box in out 3 times b4 I bought parts very expensive cheers Tom

Thank you all for your answers!

@Ramona
Do you really know it's the correct oil? Some boxes use transmission fluid oil, some engine oil and some single grade engine oil with no additives. I would suggest changing the oil to the exact specifications first and try that.
Search down a few pages on this forum and there will be a similar post on the same engine and saildrive.

The oil that the manufacturer recommends is: Quality: API, CC or CD, MILL-L-4615 and viscosity SAE 30. The capacity for the saildrive is 3.3 liters.
As I found out the previous owner has used until now: API GL 1 & 3, SAE 90. You think this may be a significant difference?
Thanks for the info for the earlier post. I found some info helpful.

@chris340 and @garymalmgren

I have a feeling that Fillipos is not in the land of Oz.

True. The boat is in Greece but i have found this forum really helpful so i thought to ask your opinion.

1. Identify gearbox correctly.

I believe i have identified the gearbox and saildrive. It's this one: lmklubben.dk/onewebmedia/Bukh%20Sejldrev.pdf
So i believe that number 54 (030D5008) has to be changed. The replacement part i found is this: www.bukh-bremen.de/hersteller/bukh/bukh-lamellensatz-f--saildrive-bw7-alt-pm-030D5008 but with a lower price at 500 Euros from Bukh Greece.

You may, or may not have to haul the boat out for an oil change. Again, that will depend on the make & model of the sail drive.

I believe i have to change the oil by taking the boat out as stated in page 21 of this manual: www.manualslib.com/manual/1001863/Bukh-Dv-10-M.html?page=21#manual

2. Contact maker for the latest recommendation for oil. (grade and quantity)
Ask them if they recommend adding a flushing oil , run and drain.

I will contact Buck for their advice on this. But i cannot drain the oil on water. So i will need to take the boat out and test the engine while on land? Is this possible with a water tank or something like this? You have any experience on this?

@saltytom2
There is a taper on dog gears coated in a substance that wears out allowing gear to slip forward and reverse are same dog gears are inter changeable so if forward is problem to get you out of trouble you can get forward lose reverse Bench test main shaft will seem perfect but not my engineer and self had box in out 3 times b4 I bought parts very expensive cheers Tom

This is a solution that an engineer here proposed as the problem is in the forward. But i am thinking that if i buy the used gearbox and saildrive (which the seller states is in very good condition) of 1000 Euro will be a good solution also for future repairs as i will have a lot of spare parts, which are also expensive, and also i will not have to repair the current gearbox.
You think is worth it?

When you look at this manual www.marinesurveyorontario.com/BukhDV10L.pdf (I may not be correct for your engine/saildrive though) it lists SAE90 for the saildrive

Regards Don

Filippos said..

Ramona said..

The oil that the manufacturer recommends is: Quality: API, CC or CD, MILL-L-4615 and viscosity SAE 30. The capacity for the saildrive is 3.3 liters.
As I found out the previous owner has used until now: API GL 1 & 3, SAE 90. You think this may be a significant difference?
Thanks for the info for the earlier post. I found some info helpful.

That's diff oil for a car in there! Clean that out and flush if you can and try the cheapest single grade SAE 30 oil you can find. SAE 30 oil has very little in the way of additives. Use the same oil in your engine if it's specified. Do not use high pressure oil in the saildrive!

Ok thank you. I will find SAE30 and change that.

Donk107 said..
When you look at this manual www.marinesurveyorontario.com/BukhDV10L.pdf (I may not be correct for your engine/saildrive though) it lists SAE90 for the saildrive

Regards Don

The printed copy of the handbook i have on the boat states SAE30. I cannot find it on the internet but it is almost the same as this handbook:
www.manualslib.com/manual/1001863/Bukh-Dv-10-M.html?page=31#manual

Hi Filippos

I don't suppose you can take a photo of the page in your handbook where it lists the oil type and post it on here because on the link you posted I can't see where it lists the type of saildrive oil only oil for the ZF gearbox if fitted with a shaft

Regards Don

Although a larger engine, I also use a gearbox from ZF (straight shaft) with spec saying SAE30 oil.

So it may be prudent to make sure your Bukh hard copy manual references the saildrive, rather than the shaft gearbox, because that may explain the discrepancy with Donk's manual.

Filippos said..

Hi Don,

I uploaded the photo of the pages. It says that the quality of the oil shall be the same as the marine gear so i suppose it's SAE30.

Sail drive spec is half shown on p30 - what's on page 31 ?

Karsten said..

Filippos said..

Hi Don,

I uploaded the photo of the pages. It says that the quality of the oil shall be the same as the marine gear so i suppose it's SAE30.

Sail drive spec is half shown on p30 - what's on page 31 ?

Hi Karsten,

Page 31 has no further info regarding lubrication.

Good job, Sam


Gary

LooseChange said..
OK, this is straight from the workshop manual for the type DV10 / 20

Oil Change and Gear Ratio
As an alternative to the BW7 gear the DV36 can be equipped with a sail drive.
The reduction ratio is 2.25:1 for "AHEAD" and 2.25:1 for "REVERSE".
The sail drive will need no other attendance than regular change of oil. This to be carried out after
the first 25 hours of operation and then every 150 hours or once a year.
Carry out the oil change when the boat is on land by loosening the drain screw in the bottom of the
sail drive enabling the oil to run out.
Refill with fresh oil through the filler hole at the top of the sail drive to a quantity of 3.3 litres
corresponding to the upper mark on the dip stick.
Use the same quality of oil as for the BW7 gear.



BW 7 Gearbox
Quality of lubricating oil marked Service CC or CD with a viscosity of SAE 30 or SAE15W-40
is used. Oils covering more viscosity numbers must not be used.

The workshop manual can be downloaded from Bukh as a PDF

It's a worry the Bukh guys in Sydney can't read a manual!

I personally would just use SAE 30, the multigrades like SAE15-40 are hard to find easily now and probably have too many additives.

Ramona said..

LooseChange said..
OK, this is straight from the workshop manual for the type DV10 / 20

Oil Change and Gear Ratio
As an alternative to the BW7 gear the DV36 can be equipped with a sail drive.
The reduction ratio is 2.25:1 for "AHEAD" and 2.25:1 for "REVERSE".
The sail drive will need no other attendance than regular change of oil. This to be carried out after
the first 25 hours of operation and then every 150 hours or once a year.
Carry out the oil change when the boat is on land by loosening the drain screw in the bottom of the
sail drive enabling the oil to run out.
Refill with fresh oil through the filler hole at the top of the sail drive to a quantity of 3.3 litres
corresponding to the upper mark on the dip stick.
Use the same quality of oil as for the BW7 gear.



BW 7 Gearbox
Quality of lubricating oil marked Service CC or CD with a viscosity of SAE 30 or SAE15W-40
is used. Oils covering more viscosity numbers must not be used.

The workshop manual can be downloaded from Bukh as a PDF

It's a worry the Bukh guys in Sydney can't read a manual!

I personally would just use SAE 30, the multigrades like SAE15-40 are hard to find easily now and probably have too many additives.

Hi Ramona,

Are you suggesting to use SAE 30 in a dog clutch arrangement? Or

A disc/cone type clutch gearbox?

The Bukh guys (as per Sam's post) seem to be assuming it's a dog clutch & are recommending 90 gear oil for that application.

I'm going through this same process at the moment. I just had my dog gears re-cut and need to be certain about the oil.

Sorry about the thread hijack.

Cheers Chris.

Filippos said..
Hello,

Thanks @samsturdy for the info but i have different info.
This is the spare parts catalog of the saildrive: lmklubben.dk/onewebmedia/Bukh%20Sejldrev.pdf
There is a multiple disk couling there (No 54).
I cannot see why Bukh sais there is dog drive.
For the oil i cannot find any more info. I think the most suitable from the handbook is SAE30.

Filippos, here is the link to the manual directly from Bukh. It will tell you everything you need to know.

http://bukh.dk/upload_dir/docs/FAQ/BukhME-Data/BukhME-10-20ME/Bukh20ME-Manuals/Worksshopmanual/WorkShopManual-BUKHDV20ME.pdf

chris340 said..

Hi Ramona,

Are you suggesting to use SAE 30 in a dog clutch arrangement? Or

A disc/cone type clutch gearbox?

The Bukh guys (as per Sam's post) seem to be assuming it's a dog clutch & are recommending 90 gear oil for that application.

I'm going through this same process at the moment. I just had my dog gears re-cut and need to be certain about the oil.

Sorry about the thread hijack.

Cheers Chris.

No I'm suggesting using exactly what the factory specifies. I would not accept advice over the phone from a "Specialist". If the answer is 90 gear oil tho make sure it is exactly the correct specification 90 gear oil. Slight variations for a better, modern oil can have interesting results. The factory knows best!