Vegetable oil in saildrive?

[seamuffin]

Hi folks -

I have on older Bukh DV36 with saildrive - had to replace the lower leg last year, and the "new" one started getting water in the oil - so I hauled the boat and changed the seals, but it's still happening. Not in the budget to haul again and faff around trying to diagnose it - want to wait for my next "regular" haulout, so I wondered if I could make a header tank for it for now and use vegetable oil so nothing nasty would be leaking out into the ocean - would that work? Like maybe something with a higher temperature tolerance, like peanut oil? Does that seem... possible?

Thanks!

JAE in Oslo, Norway

 

[westernman]

Hi folks -

I have on older Bukh DV36 with saildrive - had to replace the lower leg last year, and the "new" one started getting water in the oil - so I hauled the boat and changed the seals, but it's still happening. Not in the budget to haul again and faff around trying to diagnose it - want to wait for my next "regular" haulout, so I wondered if I could make a header tank for it for now and use vegetable oil so nothing nasty would be leaking out into the ocean - would that work? Like maybe something with a higher temperature tolerance, like peanut oil? Does that seem... possible?

Thanks!

JAE in Oslo, Norway

You can get vegetable based hydraulic oils.
This would be better than something from your local food shop.

 

[VicS]

Hi folks -

I have on older Bukh DV36 with saildrive - had to replace the lower leg last year, and the "new" one started getting water in the oil - so I hauled the boat and changed the seals, but it's still happening. Not in the budget to haul again and faff around trying to diagnose it - want to wait for my next "regular" haulout, so I wondered if I could make a header tank for it for now and use vegetable oil so nothing nasty would be leaking out into the ocean - would that work? Like maybe something with a higher temperature tolerance, like peanut oil? Does that seem... possible?

Thanks!

JAE in Oslo, Norway

It does not sound at all sensible to use anything other than the recommended oil. Sensible course of action is to haul out and fix properly.or you risk expensive repairs to the saildrive.
You say you fitted new seals but did you examine the prop shaft for wear, or was it new?
Did you fit a new seal on the oil drain screw?

 

[Blue Seas]

100% agree with VicS, many vegetable (and hydraulic) oils are hygroscopic - the very last thing that you want in a sail drive that may have a direct leak to salt water. It has to be done properly to avoid big bills down the line imho.

 

[ash2020]

Vegetable oils also rot rubber seals. I ran a van on it once and the seals in the lift pump failed pretty quickly. You would need to use nitrile seals.

 

[vyv_cox]

Gears need boundary lubricants that are sufficient in some engine oils but non existent in vegetable oil. Vegetable based hydraulic oils presumably have them but they are new to me. Scuffing of the gears will occur without boundary lubricants.

 

[westernman]

Gears need boundary lubricants that are sufficient in some engine oils but non existent in vegetable oil. Vegetable based hydraulic oils presumably have them but they are new to me. Scuffing of the gears will occur without boundary lubricants.

Available from this forum's favourite oil supplier:-
Terralus BVG 68 Biodegradable Hydraulic Oil

 

[seamuffin]

Spec for this drive is SAE 30. And yes, of course I would love to haul out and fix properly but there are other things on the list at the moment - mainly because I didn't plan on hauling out the first time (long story with mechanic who was supposed to overhaul the drive and install it in the first place but just... didn't... and I had to have the yard where the boat was sitting install it in order to get it in the water and they didn't check things etc. etc...

What about something like this?

Oregon Bio sagkjedeolje for motorsag og hogstmaskin 1 l | Clas Ohlson

 

[Beneteau381]

Spec for this drive is SAE 30. And yes, of course I would love to haul out and fix properly but there are other things on the list at the moment - mainly because I didn't plan on hauling out the first time (long story with mechanic who was supposed to overhaul the drive and install it in the first place but just... didn't... and I had to have the yard where the boat was sitting install it in order to get it in the water and they didn't check things etc. etc...

What about something like this?

Oregon Bio sagkjedeolje for motorsag og hogstmaskin 1 l | Clas Ohlson

Other things on the list! Really? A really expensive piece of kit and you want to bodge it? Fix it, properly!

 

[seamuffin]

Other things on the list! Really? A really expensive piece of kit and you want to bodge it? Fix it, properly!

Sigh. I want to keep it from getting worse until I have the time and money to fix it properly. I do not have a lot of extra money lying around and I’m busier than I would like to be. Please stop yelling at me, not all of us have a pristine pretty yacht straight from the factory.

 

[KevinV]

Spec for this drive is SAE 30. And yes, of course I would love to haul out and fix properly but there are other things on the list at the moment - mainly because I didn't plan on hauling out the first time (long story with mechanic who was supposed to overhaul the drive and install it in the first place but just... didn't... and I had to have the yard where the boat was sitting install it in order to get it in the water and they didn't check things etc. etc...

What about something like this?

Oregon Bio sagkjedeolje for motorsag og hogstmaskin 1 l | Clas Ohlson

I don't read that language but I'm guessing that's chain oil? Really gloopy, and designed for almost zero working life - I can't imagine it being suitable.
All oil is biodegradable in small quantities, I'd be more inclined to worry about damage to the sail drive rather than to the environment unless it's pouring out.

 

[Fr J Hackett]

just how much oil is leaking out? Also if oil is leaking out eventually water will leak in. Do yo plan to use the boat in its current state or just leave it till you can afford to rectify the problem? All things that could influence what you do.

 

[Boathook]

Sigh. I want to keep it from getting worse until I have the time and money to fix it properly. I do not have a lot of extra money lying around and I’m busier than I would like to be. Please stop yelling at me, not all of us have a pristine pretty yacht straight from the factory.

My boat is nearly 50 years old and there are some things I cut back, on but not engine related. You will just have to bite the bullet and spend the money or spend even more later.

 

[Baddox]

It’s a great idea using vegetable oil, then when water gets in you’ll have edible mayonnaise. Apart from that, vegetable oil can hydrolyse or oxidise over time to form fatty acids which will make your saildrive even less happy, plus it can cross-link to form gel or thick gloop. Plus it won’t have the right lubrication to protect the high pressure contact areas in the hears, plus there will be no corrosion inhibitors in the oil to protect the metal or plastic seals, etc.

 

[Tranona]

Your saildrive is literally irreplaceable except with another potentially dodgy used one so you need to love it. It sounds like the shaft is worn which can be fixed relatively easily by sleeving it.

 

[ChromeDome]

Sigh. I want to keep it from getting worse until I have the time and money to fix it properly. I do not have a lot of extra money lying around and I’m busier than I would like to be. Please stop yelling at me, not all of us have a pristine pretty yacht straight from the factory.

Point taken but please understand the advice given here is valid.
You have to appreciate that people don't just agree with you when you're heading off a bad route. If you feel people are yelling it might be to point you in a better direction.

It's a bit inappropriate to expect the majority here to read/speak Norwegian, but you could extract the facts and Google

"Biologisk nedbrytbar" sae 30 motorolje -kjedeolie

Bio oils are also used in agricultural machinery, so consider this.

 

[seamuffin]

Your saildrive is literally irreplaceable except with another potentially dodgy used one so you need to love it. It sounds like the shaft is worn which can be fixed relatively easily by sleeving it.

This is exactly the problem. I had a saildrive that was truly and utterly borked (haven't torn it apart yet to see what the problem was, but it was uneven - sticking - and eating gearbox clutches - and had to replace it with this dodgy used one. I would like to repower eventually, as this engine has been done hard by.

 

[ChromeDome]

I would like to repower eventually, as this engine has been done hard by.

Now that is a different story and a reason to keep it alive - just!

Repowering would require a different budget, so consider the realistic resale value against investment, before placing an order.
Could very well be better to buy another boat in "just add water" condition.

 

[seamuffin]

Now that is a different story and a reason to keep it alive - just!

Repowering would require a different budget, so consider the realistic resale value against investment, before placing an order.
Could very well be better to buy another boat in "just add water" condition.

Ah yes, but there is the irrational love one has for a boat!

 

[Boater Sam]

Cut the losses, change the oil and sell the boat. Buy one that works.