Oil in a PRM gearbox

[BeninReading]

Hello all,

 

I recently established (judging by the name on it), that my gearbox is a PRM, which pleases me seeing some of the comments about it on this site!! I have heard a lot of bad things about Technodrive gearboxes (yes, I have a Vetus). Within the near future I wish to change my gearbox oil, but have no manual or information on what new oil to put back in?? Can anyone help??

 

Thanks to everyone in advance.

 

Regards, Ben

[alan_fincher]

If it's definirely a Newage PRM, then the answer is always the same.....

 

The same stuff that goes in your engine....

 

As Newage told me "if it's good enough for the engine, it's more than good enough for the gearbox".

[churchward]

Yep oil same as goes in the engine is fine on all types even the mechanical PRM 80 and 120 models.

 

It has always tickled me ( am am easily amussed!) that PRM hydraulic gearboxes use engine oil and things like Hurth Mechanical boxes use Auto box ATF oil. Still, it's just the way they are engineered.

[alan_fincher]

Also you might like to download an owners handbook from here......

 

http://www.prm-marine.com/owners_handbook.php

[David Schweizer]

Although the latest instructions suggest 10W30 oil for normal operating temperatures for the 160 (260) box, the information I received from Newage some 10 years ago was "put the same oil in the gearbox as you put in the engine". When I said I use Morris SAE30, they said that was fine.

[oggie]

Just agreeing with everyone, whilst at a show last year I asked PRM what oil should I use in my gearbox and was told to use the same as I use in the engine, very handy.

[blackrose]

The other thing to note is that with a PRM (or at least with the 150), you're supposed to screw the dipstick right down to take an oil level reading. Either that or don't screw it down and just make a mark on your dipstick to compensate for the extra distance. It would help if Newage made the end of the dipstick on the PRM150 flat - new oil on a round dipstick is very difficult to see.

[Guest]

Hello all,

 

I recently established (judging by the name on it), that my gearbox is a PRM, which pleases me seeing some of the comments about it on this site!! I have heard a lot of bad things about Technodrive gearboxes (yes, I have a Vetus). Within the near future I wish to change my gearbox oil, but have no manual or information on what new oil to put back in?? Can anyone help??

 

Thanks to everyone in advance.

 

Regards, Ben

Now that you have got a conclusive answer, may I ask if your Vetus came with a PRM as standard?

 

Many thanks.

[David Schweizer]

The other thing to note is that with a PRM (or at least with the 150), you're supposed to screw the dipstick right down to take an oil level reading. Either that or don't screw it down and just make a mark on your dipstick to compensate for the extra distance. It would help if Newage made the end of the dipstick on the PRM150 flat - new oil on a round dipstick is very difficult to see.

I agree, it is very difficult to see the oil, and as it never seems to get dirty, it is always difficult.

 

Who is going to be the first person to experiment with filing a flat face on the fairly thin dip stick?

Edited March 30, 2009 by David Schweizer

[Keeping Up]

Some people use very expensive oil in their engine. However presumably if, say, cheap supermarket 20W50 is good enough for a PRM when it is mated to an engine which uses cheap 20W50, then that same oil would be good enough for the same gearbox when it was mated to a different engine which happened to use an expensive oil. So I would interpret PRM's advice as meaning "just use any type of engine oil".

 

The best way I know to read the oil level is to roll the dipstick along on a piece of kitchen roll or loo paper. The oil level shows clearly on the paper. Note also that if you don't screw the dipstick in, the bottom mark on the dipstick is now positioned roughly where the top mark should be. So your level won't be far out, if it's just below the bottom mark when you don't screw the dipstick.

[nb Innisfree]

When I phoned Newage they said same oil as engine, I said how often? they said same as engine, I said I have Canal Star, every 100 hrs? they said yes that's right, I said what if g'box is on a Kubota, 250hrs? they said yes that's right, I said which one is right? They said both, or do it once or twice a year. I said can I use any engine oil? they said yes that's right!

[Guest]

When I phoned Newage they said same oil as engine, I said how often? they said same as engine, I said I have Canal Star, every 100 hrs? they said yes that's right, I said what if g'box is on a Kubota, 250hrs? they said yes that's right, I said which one is right? They said both, or do it once or twice a year. I said can I use any engine oil? they said yes that's right!

So it would seem if you change the oil once in a while, and stick some multigrade diesel oil in, you are fine

[nb Innisfree]

So it would seem if you change the oil once in a while, and stick some multigrade diesel oil in, you are fine

I forgot to mention, I asked if I could use monograde 30 oil, they said yes! They didn't say you couldn't use non diesel engine oil, oh my god not more decisions!

[alan_fincher]

Some people use very expensive oil in their engine. However presumably if, say, cheap supermarket 20W50 is good enough for a PRM when it is mated to an engine which uses cheap 20W50, then that same oil would be good enough for the same gearbox when it was mated to a different engine which happened to use an expensive oil. So I would interpret PRM's advice as meaning "just use any type of engine oil".

I agree,

 

In fact I have been steadily working my way through some cheapish oil that turned out to be a "higher" API-CF spec, so deemed unsuitable for my engine. When that's all gone I shall attack the Morris Supreme monograde that I have, which I decided the engine wasn't too keen on. So it could be year or two yet before I have to buy any gearbox oil.

 

I change whenever I do the engine - so easy, and so little oil, I see no reason why not too, even if overkill.

 

As to oil levels, in most things I would take them when everything was settled. Note that PRM say you should run the gearbox first, and only then measure the level - this is so the oil cooler is guaranteed to be full, and you don't get a falsely high reading. I've never found it makes much difference though....

 

Totally agree about the dipstick - an awful piece of design.

[Guest]

I forgot to mention, I asked if I could use monograde 30 oil, they said yes! They didn't say you couldn't use non diesel engine oil, oh my god not more decisions!

I would have been tempted to ask if water was suitable after all of those "yes" replies

[David Schweizer]

I agree,

 

In fact I have been steadily working my way through some cheapish oil that turned out to be a "higher" API-CF spec, so deemed unsuitable for my engine. When that's all gone I shall attack the Morris Supreme monograde that I have, which I decided the engine wasn't too keen on. So it could be year or two yet before I have to buy any gearbox oil.

 

I change whenever I do the engine - so easy, and so little oil, I see no reason why not too, even if overkill.

 

As to oil levels, in most things I would take them when everything was settled. Note that PRM say you should run the gearbox first, and only then measure the level - this is so the oil cooler is guaranteed to be full, and you don't get a falsely high reading. I've never found it makes much difference though....

 

Totally agree about the dipstick - an awful piece of design.

I seem to remember you saying that your engine did not like Morris Supreme 30 when we were locking down somewhere together. Was it because of smoking? I have heard some people say that their BMC 1.5 smokes less when on multigrade, is that your experience, or is it something more complicated than that?

[Bigboat]

Hi

Yes you can use any engine oil but not highly synthetic that can mess up the seals, most canal boat engines use either straight monograde or low synthetic multigrade oils which is fine.

[alan_fincher]

I seem to remember you saying that your engine did not like Morris Supreme 30 when we were locking down somewhere together. Was it because of smoking? I have heard some people say that their BMC 1.5 smokes less when on multigrade, is that your experience, or is it something more complicated than that?

Yes David,

 

Our 1.8 seems to smoke less, (but still smokes!) on a multi-grade.

 

Also it doesn't "use" anything like as much - i.e. I have to put some in between oil changes a lot less frequently.

 

I'm still not convinced I'm using the optimum oil in our engine, (which has almost certainly not been opened up since Calcutt rebuilt it 13 or 14 years ago).

 

I'm currently using Lister Petter, an API-CC oil, blended I believe my Morris, and which our local engineers says is the mutt's nuts, and fine in a BMC.

 

However it's only a 10W-40, whereas the handbook indicates a 20W-50 is correct. Also my chandlery now want £19-50 for it, (£14-50 last time at Uxbridge Boat Centre).

 

If I could find an easy source for a 20W-50, without buying a tanker-load, I might try it. We are boating again by the end of the week, so I'll keep my eyes open.

 

Although B&Q are supposed to do one, they no longer seem to have any motoring stuff in the branch I visited.

[churchward]

Yes David,

 

Our 1.8 seems to smoke less, (but still smokes!) on a multi-grade.

 

Also it doesn't "use" anything like as much - i.e. I have to put some in between oil changes a lot less frequently.

 

I'm still not convinced I'm using the optimum oil in our engine, (which has almost certainly not been opened up since Calcutt rebuilt it 13 or 14 years ago).

 

I'm currently using Lister Petter, an API-CC oil, blended I believe my Morris, and which our local engineers says is the mutt's nuts, and fine in a BMC.

 

However it's only a 10W-40, whereas the handbook indicates a 20W-50 is correct. Also my chandlery now want £19-50 for it, (£14-50 last time at Uxbridge Boat Centre).

 

If I could find an easy source for a 20W-50, without buying a tanker-load, I might try it. We are boating again by the end of the week, so I'll keep my eyes open.

 

Although B&Q are supposed to do one, they no longer seem to have any motoring stuff in the branch I visited.

 

On previous evidence you probably won't believe me but it is not likely that it is a Mono V multigrade issue with your engine. Simply SAE30 is too thin for an older engine when fully warm. Assuming the smokiness doesn't go away when it warmed up. 20w/50 remains a thicker oil when warm (the 50 bit) so will help with smoking when warm. An SAE50 or even SAE40 monograde would achieve the same result accept that apart from the summer months such a monograde may be too thick for cold start protection.

 

The Petter 10W40 if made by Morris is probably similar to their Golden film "canal boat" oil product. Unless your engine is particularly warn and really needs the thickness of the 20W/50 it should be OK. The thinness when cold can really help in the winter for cold starts but then if you don't use the boat much in the winter that won't matter. A good classic or otherwise 20w/50 is likely to be much cheaper too.

 

You could try Castrol Classic XL 20w/50 (which is basically the old fashioned blend that was the original GTX) it has a low detergent content equivalent to API-CC you can get it in gallon or 25 litre amounts. It is not the cheapest but a very good oil for engines that do need low detergent levels. 25 litres can be had for around £85 inc vat so about £17 per 5 litres.

Edited March 30, 2009 by churchward

[alan_fincher]

On previous evidence you probably won't believe me but it is not likely that it is a Mono V multigrade issue with your engine.

Oh dear! - I really can't remember the history of why I shouldn't believe you!

 

Actually, none of what you say surprises me, and is more or less in line with my own thinking, (although David will probably pop up and say that a straight SAE 30 is listed as an acceptable oil in the original BMC handbook - which it is, of course!).

 

What I have used up to now has been largely dictated by what I can buy when I need it, without travelling for it, (although recommendation also played it's part).

 

However our engine is pretty elderly, and of unknown rebuild or service history. I can't help thinking a 20W-50 may suit it better than the 10W-40.

 

It starts pretty well, (for a BMC!), even in the thick of winter, so I think would still turn over fast enough on the thicker oil.

 

I can't see why an Asda or B&Q API-CC oil at £10 per litre is not as good as a branded one at perhaps twice that - I just can't easily find one.

 

Thanks for your helpful thoughts.

[churchward]

Oh dear! - I really can't remember the history of why I shouldn't believe you!

 

Actually, none of what you say surprises me, and is more or less in line with my own thinking, (although David will probably pop up and say that a straight SAE 30 is listed as an acceptable oil in the original BMC handbook - which it is, of course!).

 

What I have used up to now has been largely dictated by what I can buy when I need it, without travelling for it, (although recommendation also played it's part).

 

However our engine is pretty elderly, and of unknown rebuild or service history. I can't help thinking a 20W-50 may suit it better than the 10W-40.

 

It starts pretty well, (for a BMC!), even in the thick of winter, so I think would still turn over fast enough on the thicker oil.

 

I can't see why an Asda or B&Q API-CC oil at £10 per litre is not as good as a branded one at perhaps twice that - I just can't easily find one.

 

Thanks for your helpful thoughts.

 

 

The main reason some cheaper oils will be a little inferior is that the base oil for refinement will be of lower quality to start with and will "age" or breakdown faster in your engine. Secondly a lot of inferior oils have poorer "coating" attributes better oils cling onto the metal parts better (like Castrol boast about in their Magnetec oils) when stationary with a thicker coating. If the oil falls away more it can't help as well in those few seconds at start-up from cold.

 

Having said that with the frequency we tend to change the oil on our NBs I would say the difference in performance is going to be small.

 

By the sound of it your older engine is a bit sloppy so will benefit from the thicker 20w/50 oil when warm. The oil will find it more difficult to get by the oil control rings on the pistons and also down the valve guides on a BMC.

 

One old trick to stop a smokey A or B series was to fit the oil caps on the valve guides normally only used for the inlet valves on the exhaust ones too. However this only works for a while as the guides benefit from a bit of oil so stopping the flow makes the exhaust guides wear faster.

 

P.S.

 

If your BMC has managed to last 13 or 14 years without major work and only smoking a bit then I think it is coping well and best to keep doing what your doing.

Edited March 30, 2009 by churchward

[Richard T]

To overcome the dipstick problem I simply made a wooden one out of a piece of kindling with the marks cut in the right place. It is L shaped so that it can't drop into the gearbox. Simple to use and fairly fool proof we even have a spanner designated for use on the dipstick. If its simple people will do it!! KISS rules Ok.

[RobinJ]

The other thing to note is that with a PRM (or at least with the 150), you're supposed to screw the dipstick right down to take an oil level reading. Either that or don't screw it down and just make a mark on your dipstick to compensate for the extra distance. It would help if Newage made the end of the dipstick on the PRM150 flat - new oil on a round dipstick is very difficult to see.

You should find that the maximum mark on the dipstick works just the same with the dipstick in as the bttom of the dipstick with it out!

[Theo]

You should find that the maximum mark on the dipstick works just the same with the dipstick in as the bttom of the dipstick with it out!

 

How often should you change the oil in a PRM?

[GSer]

To overcome the dipstick problem I simply made a wooden one out of a piece of kindling with the marks cut in the right place. It is L shaped so that it can't drop into the gearbox. Simple to use and fairly fool proof we even have a spanner designated for use on the dipstick. If its simple people will do it!! KISS rules Ok.

 

 

I just rest the dipstick on a piece of paper/rag its easy to see the level then?