Volvo Penta AD31b's Oil recommendations

[Frontier]

Volvo Penta AD31b\'s Oil recommendations

I need to change my oil, the manual says its 15w / 40 API = CD

Should I use mineral or synthetic?

I would have thought synthetic as its turbo charged,

Which brand?

Thanks in advance

 

[hlb]

Re: Volvo Penta AD31b\'s Oil recommendations

Though my boat had synthetic in for many years. My mechanic said it was not good for older engines.

It dont matter what make of oil you buy. Most today are suitable for all engines and will be above 15w / 40 API = CD. So look on the can.

Or it will say diesel turbo plus this or that.

I had an expencive love affair with synthetics. No longer.

 

[Frontier]

Re: Volvo Penta AD31b\'s Oil recommendations

Yes I got into synthetics too, (turbo cars) but I guess old diesels are different even if they have a turbo.

Thanks Hayden,

 

[oldgit]

Mineral fleet oil in 40A.

Have been using my local motor factors fleet oil since buying boat.
However boat is rarely used for lengthy long thrashes except for 20 min odd clear out the internal bits WOT now and then.Cannot recall having ever to top up engine mid season either.

 

[Andrew_Fanner]

Re: Mineral fleet oil in 40A.

Local Lucas/LSUK, tell them what the oil is for and go with what they offer. Cheap as chips (almost).

All the oil needed for a 41 for under £20. Annoyingly they couldn't do a filter for some reason.

 

[Chris_d]

Re: Volvo Penta AD31b\'s Oil recommendations

Try this place for cheap synthetic oil,

http://www.difflock.com/cgi-bin/wm10/wm1...ds&srch=all

You'll need 36litres for a change in 2 AD31's, they do 50litres of fully synthetic for £50, no point in using anything else at that price.

There are definate benefits to using synthetic especialy from new, but its really more important to run the engine under load reguarly and just change the oil every year regardless.

 

[Will_M]

Re: Volvo Penta AD31b\'s Oil recommendations

[ QUOTE ]
You'll need 36litres for a change in 2 AD31's

[/ QUOTE ]

Why?!?! What you going to do with the remanding 18 litres then?

31 series holds 9 litres per engine including filter at 0 degree inclination.

Incidentally, Frontier, stick to a high grade mineral 15/40 in your old 31Bs.

 

[Chris_d]

Re: Volvo Penta AD31b\'s Oil recommendations

oops /forums/images/graemlins/blush.gif sorry, yes doubled the wrong numbers, and its £42 for 25litres from Difflock, not 50litres duh...

 

[Callisto]

Re: Volvo Penta AD31b\'s Oil recommendations

Good quality mineral. Synthetic is not good in these engines. I have that on good authority from the local VP man.

From what I understand, synthetic is thiner and less viscous and designed for the closer tolerances of modern engines.

Just changed the oil in two of them. 9 litres approx. I filled the filters before i fitted them too.

Cheers

JH

 

[oldgit]

Re: Mineral fleet oil in 40A.

Oil filter from local factor 7.88 +Vat.25L 15/40 Fleet lube oil 25.00+Vat.

 

[Frontier]

Re: Volvo Penta AD31b\'s Oil recommendations

Thanks to all for the replies,

I just have to decide synthetic or mineral, I understand that the older engines might be better on mineral, but I know that turbo’s hammer the oil molecules and the inside of a turbo can reach the same temperature as a nuclear reactor, which fries mineral oil and varnishes the bearings. But I am talking cars here, maybe a boat turbo does not work so hard. It certainly doesn’t get the treatment a car turbo gets, like when the rep pulls into the services having been driving a 98mph all morning and just switches of the engine.

I believe that fully synthetic stays in grade in a car for almost 25k miles and mineral is down to 25% of its original grade after only 4k miles. But again that’s cars.

/forums/images/graemlins/confused.gif

 

[Chris_d]

Re: Volvo Penta AD31b\'s Oil recommendations

I think it comes down to price, if you can afford synthetic oil especialy from new then stick with it, however if an older engine hasn't had it before it can do more harm than good, the detergents in it may loosen deposits in the engine and this may accelerate wear. The car turbo problems don't really apply to marine engines, because they run at a constant lower temperature due to the water cooling coming from the sea. Its still a sensible precaution though to not switch off imediately after a long run, to allow the turbo to cool and the turbine to stop spinning without an oil supply.
In your case if you don't know what oil was in it before and given the age I would play safe and use a good mineral oil, then use the saving to change it more often, hence getting round the problem of the mineral oil degrading.
At the end of the day I don't know anybody who has a problem with any engine because they used a different oil, compared to say the number of water pump, outdrive, thermostat, fuel bug, filter problems etc...

 

[Frontier]

Re: Volvo Penta AD31b\'s Oil recommendations

Thanks for the advice Chris,

I gather you can't get CD rated oil now do you know what API to look for

D

 

[Chris_d]

Re: Volvo Penta AD31b\'s Oil recommendations

The API rating should have a "C" in it for to be suitable for "Compression igintion engines" and "S" is for sparkers! The rating goes from A to J , J being the highest rated, so a CJ would be the best, but in my Volvo book it says use CD. So you might have to lower your standards for these old green lumps /forums/images/graemlins/grin.gif

 

[[2068]]

Re: Volvo Penta AD31b\'s Oil recommendations

Volvos latest "Diesel Oil" is a 15/40W API CG, although my manual recommends API CH, and that's for the AD31 as well...

dv.