PRM 150 Gearbox Oil

[Alway Swilby]

I have a Beta 43 with a PRM 150 gearbox. Every time I change the engine oil and filter it takes about 9 litres. I tend to be purchase oil in 2 x 5 litre containers from wherever it is available at the time, sometimes Halfords sometimes a back street motor spares shop. So this leaves me with about a litre of oil left over at each service. Rather than store a load of 5 litre containers each with 1 litre in it I mix all these litres of different oils together and store them in one container. The gearbox oil is due a change at the next service, will it be ok to use this left over mixed (but unused) oil in the gearbox?

 

[RLWP]

Yes

[Sea Dog]

In their gearbox manual, PRM specifically say not to mix different brands, types or grades of oil. The 150 only takes 1.4 litres and has a pressure range of 370 to 420 psi  - I'd be inclined to change that first using new oil from a sealed container and leave any mixing to occur in the engine oil if must needs. Why not just make sure you always buy the same stuff, then you don't have the issue?

[mross]

But it would be better not to mix 5 new oils.  If each uses different additives the additives will be much diluted from their original concentration.  But any risk is small.

[MHS]

3 hours ago, mross said:

But it would be better not to mix 5 new oils.  If each uses different additives the additives will be much diluted from their original concentration.  But any risk is small.

It’s a bit like a blended whisky. A single malt would always be preferable. 

We also have a Beta 43 and PRM150. The boat is 3 1/2 years old now, so rarely needs oil between services. We try to get the same oil, last time we bought 20L so we can do the two required services this year without the issue the OP had. 

[Dr Bob]

Go to Costco me buy a 20lt container of oil. Much cheaper and fine if you are changing every 200 hrs. We have a beta 43 and it seems more like 7-8 litres rather than 9. Must remember to do the gear box soon!!

Edited October 19, 2017 by Dr Bob

[Dr Bob]

Don't forget the modern day oils are designed for 70mph plus up and down motorways for 10,000 miles plus. A bit more strenuous than tick over up and down the cut. I know nothing about NB gearboxes but how many fail due to mixed oil lubrication? That is a serious question? I think I am up to 400 hrs since buying our boat and not changed the gearbox oil yet! Must do it soon. 

[cuthound]

PRM now recommend oil changes for the 150 every 750 hours. 

I change mine every 2 years or 750 hours, whichever comes first.

[john6767]

8 hours ago, Dr Bob said:

Don't forget the modern day oils are designed for 70mph plus up and down motorways for 10,000 miles plus. A bit more strenuous than tick over up and down the cut. I know nothing about NB gearboxes but how many fail due to mixed oil lubrication? That is a serious question? I think I am up to 400 hrs since buying our boat and not changed the gearbox oil yet! Must do it soon. 

You are not using a "modern" oil, you are using a mineral based oil.  Modern synthetic oils are suited to the 12,000 mile once a year change on a car, the mineral ones are in a car context, oil changes every 6,000 as you used to do. 

You are fine on the gearbox, assuming it is PRM150, it is every 750 hours, although from new I personally would change it early.  When we bought out boat second hand it had done 700 hours and judging by the paint the gearbox oil had not been changed, and it does not seem to have some to any harm.

[Dr Bob]

1 hour ago, john6767 said:

You are not using a "modern" oil, you are using a mineral based oil.  Modern synthetic oils are suited to the 12,000 mile once a year change on a car, the mineral ones are in a car context, oil changes every 6,000 as you used to do. 

You are fine on the gearbox, assuming it is PRM150, it is every 750 hours, although from new I personally would change it early.  When we bought out boat second hand it had done 700 hours and judging by the paint the gearbox oil had not been changed, and it does not seem to have some to any harm.

I was actually referring to the mineral based oils which are modern with very good additive packages so you can get 6000 miles - I was a bit optimistic in my first post. No problem chugging down the cut.

thanks for the hours info. ....and to cuthound as well.

Edited October 20, 2017 by Dr Bob

[RLWP]

Before getting too paranoid, if you use a Pela pump or similar to extract the oil, you usually get only two thirds of it out. So, when you put in the new stuff you are already mixing oils

Richard

[bizzard]

1 hour ago, RLWP said:

Before getting too paranoid, if you use a Pela pump or similar to extract the oil, you usually get only two thirds of it out. So, when you put in the new stuff you are already mixing oils

Richard

Oil agree with that.

[WotEver]

4 hours ago, bizzard said:

Oil agree with that.

So did Olive. 

[Markblox]

On 20/10/2017 at 07:53, cuthound said:

PRM now recommend oil changes for the 150 every 750 hours. 

I change mine every 2 years or 750 hours, whichever comes first.

No they don't!  I have just downloaded the maintenance PDF from PRM and it says do it at the same interval as the engine which on a 43 is 250Hrs.  It's a simple job.

[blackrose]

Maybe Cuthound's engine manufacturer recommends oil changes every 750 hours, in which case for his engine he's correct.

 

Anyway, you do realise that you were responding to a post that's nearly 4 years old?

[Idle Days]

53 minutes ago, blackrose said:

Maybe Cuthound's engine manufacturer recommends oil changes every 750 hours, in which case for his engine he's correct.

 

Anyway, you do realise that you were responding to a post that's nearly 4 years old?

 

Still relevant though.  

[blackrose]

54 minutes ago, Idle Days said:

 

Still relevant though.  

 

Yes a lot of the forum archives are still relevant. It just depends on how far one wishes to dig back into them and resurrect old threads to tell someone they were wrong.

Edited August 7, 2021 by blackrose

[Sea Dog]

I'd be surprised if the PRM150 can tell what engine it's connected to, or if it makes a difference. I think I've read 750 hours somewhere for the PRM150, but my manual says every engine oil change which is 250 hours. I think it's probably a case of "While you're down there .."

Oil being cheaper than gearboxes, you pays yer money...

[Bee]

Never sure about oil changes. My Beta 43 has clean looking oil before I change it, our Renault Kangoo always has black oil the day after I change it. OK there is probably chemistry involved in degradation of oil and not just colour but although I am very fussy about oil changes I can't help thinking I have got rid of many gallons of perfectly good oil over the years.

[cuthound]

11 hours ago, Markblox said:

No they don't!  I have just downloaded the maintenance PDF from PRM and it says do it at the same interval as the engine which on a 43 is 250Hrs.  It's a simple job.

 

It appears that PRM have changed the maximum recommended annual hours from 750 to 500 hours now.

 

See the attached document, under Service Definitions - Pleasure

 

https://www.prm-newage.com/p12-prm150

 

Not sure how that fits with hire or shared ownership boats which usually do well over 1000 hours per annum.

[cuthound]

11 minutes ago, Bee said:

Never sure about oil changes. My Beta 43 has clean looking oil before I change it, our Renault Kangoo always has black oil the day after I change it. OK there is probably chemistry involved in degradation of oil and not just colour but although I am very fussy about oil changes I can't help thinking I have got rid of many gallons of perfectly good oil over the years.

 

The clean looking oil just before changes in your Beta 43 is for two reasons.

 

1. You should be using CC-CF spec oil which has fewer detergents than modern car oils, and,

 

2. Your Beta 43 may have tbe optional 9 litre sump, which dilutes the contaminants in a greater quantity of oil.

 

Trust me, it does need changing at 250 hours, even though it looks clean.

[Alan de Enfield]

12 minutes ago, cuthound said:

 

It appears that PRM have changed the maximum recommended annual hours from 750 to 500 hours now.

 

See the attached document, under Service Definitions - Pleasure

 

https://www.prm-newage.com/p12-prm150

 

Not sure how that fits with hire or shared ownership boats which usually do well over 1000 hours per annum.

 

 

In the PRM manual 'use' is defined, and, all NB (being displacement vessesl) should come under the rating of "heavy commercial", but there may be an argument for "Light Commercial" use due to only partial throttle use.

Gearbox oil-changes should be either annually or at the same time as engine oil changes - whichever comes first.

 

 

 

Edited August 7, 2021 by Alan de Enfield

[cuthound]

51 minutes ago, Alan de Enfield said:

 

 

In the PRM manual 'use' is defined, and, all NB (being displacement vessesl) should come under the rating of "heavy commercial", but there may be an argument for "Light Commercial" use due to only partial throttle use.

Gearbox oil-changes should be either annually or at the same time as engine oil changes - whichever comes first.

 

 

 

 

Whilst there is no doubt that all narrowboats have displacement hulls, I would suggest that PRM are acting with caution and that their PRM150 gearboxes in most narrowboats have a very easy life. 😁

[Markblox]

Found this in the current manual that appears identical to my 2015 manual on oil changes:

Gearbox oil should routinely be changed annually or at intervals corresponding with engine oil changes, whichever occurs first. However, if the oil should become contaminated by water, or if the gearbox suffers major mechanical damage, the gearbox, oil cooler and hoses must be thoroughly flushed out and the gearbox re-filled with fresh oil to the correct specification.

 

It's such a simple task I really don't know why you wouldn't.  I did know that it was from a post that is four years ago but is still relevant and needs correcting because anyone reading might actually believe it.  I searched for the topic rather than found it by trawling through old posts and changed my engine oil on my Beta 43 and PRM 150 yesterday and was surprised that the PRM oil was darker than the engine oil.  Maybe the previous owner thought it wasn't required after reading this misinformation on the internet!

[Tacet]

PRM is refreshingly uncomplicated in its published requirements for oil types and change intervals.  No doubt it is fine for the vast majority

 

But it seems unlikely that it is fine for every conceivable engine type - if you wish to be deliberately awkward in your hypothetical choice.