Beta 43 / PRM 150 Combination

[canute]

Just oil serviced Beta 43, 9.5 litres with filter, 'attempted' an oil service on the coupled PRM 150 and extracted 1.4 litres of oil (measured), I then refilled with 1.3 litres and then checked (probably one of the hardest to read) dipstick for final fill, however dipstick showed that gearbox was overfilled? I removed excess oil in increments until I have now removed the 1.3 litres that I poured in and the dipstick still shows an overfilled box? I can't quite get my head around what's going on, any ideas?

           Copied and pasted this from PRM 150 pdf:

                                                       1.4 litres (2.5 pints) plus the amount necessary to fill the oil cooling circuit.

Beta do not state anything about filling the oil cooling circuit, either, how to do this or quantities of oil required, even if they did I can't understand why I have removed oil but the dipstick indicates an overfill, I did wonder if the box had the wrong length of dipstick, perhaps from another model. Can anyone provide me with the distances from the underside of the dipstick nut-flange to the high and low level marks on the rod, or indeed the in's and out's of the oil cooling circuit and how to fill/service? 

 

many thanks for expedited replies, wanting to move boat ASAP.

 

 

[Jen-in-Wellies]

The oil cooling circuit will be filled when the gearbox is run. Check again after running the engine in gear for a short while. This will vary from installation to installation, so the reason why PRM don't give a figure. The dipstick is measured after screwing it down.

For draining a PRM150, the most successful way of removing all the old oil is to remove the sump nut underneath the box, rather than extracting from the top. Depending on your boat, this can be hard to reach, but will ensure all the old oil is out. I've never done it, but loosening a union to the oil cooler would ensure the old oil in it and the hoses drains back.

[robtheplod]

put out some blue kitchen towel and rest the dipstick on it and you'll be able to see the levels much easier....

[Machpoint005]

2 hours ago, Jen-in-Wellies said:

The oil cooling circuit will be filled when the gearbox is run. Check again after running the engine in gear for a short while. This will vary from installation to installation, so the reason why PRM don't give a figure. The dipstick is measured after screwing it down.

For draining a PRM150, the most successful way of removing all the old oil is to remove the sump nut underneath the box, rather than extracting from the top. Depending on your boat, this can be hard to reach, but will ensure all the old oil is out. I've never done it, but loosening a union to the oil cooler would ensure the old oil in it and the hoses drains back.

 

One way of draining a PRM box is to find a 5 litre plastic container (such as the sort windscreen washer fluid comes in, among many other products) and cut a 100m by 100mm window in the flat side, far enough up that 1.5 litres of oil will still sit in the bottom. You can then wriggle the container under the gearbox, drain the sump into it, and wriggle it out again without spilling anything. 

 

It's probably a good idea to test for a fit under the gearbox before cutting the hole!

 

 

[Sea Dog]

So, you removed 1.4L, filled with 1.3, removed 1.3 and are still measuring it as overfilled? Theoretically at least, it should be pretty much empty but the oil cooler does need accounting for if you're trying to do it by capacity. Did you check the dipstick beforehand?

 

Personally, I'd press the reset button by  draining down using the sump plug, then you'd know it was truly empty before you start.

Next, it's an absolute b'stard to read the dipstick, with or without the blue roll, and it doesn't help that new oil hardly shows when the right level is achieved. My early issues stemmed from filling the box with the right amount, not allowing for the cooler circuit. The dipstick always came out with some oil on it, making it look like it was somewhere near when in reality it was a fair bit short, so I was adding a tiny amount at a time. Eventually, it became a tiny bit more obvious that I'd started dipping oil, not just getting the dipstick damp. Once you're past this, you'll be a bit more confident next time. Iirc, mine takes 1.9L.

Lastly, use the dipstick lower mark to check as you fill - that way you can sit it in to test the level rather than screw and unscrew every time. 

 

Further to @Machpoint005 point above, I use a 4pt milk bottle with a hole cut out - on my boat, nothing larger will come out once the old oil goes in!@Machpoint005

[GUMPY]

The dipstick on a PRM has two marks. The distance between these marks is the same as the distance between the lower mark and the end of the stick. Coincidentally it is also the same distance as the thread in the cap.

So one can check the oil level without screwing the dipstick in 😱.  Just use the bit between the lower mark and the end of the stick as the gauge, not the bit between the marks.

 

 

 

Edited September 29, 2023 by GUMPY
Syntax

[cuthound]

Painting the dipstick with matt black paint or using an indelible marker to just above ad just below the two marks makes it a bit easier to see where the oil level is.

[Tracy D'arth]

Chalk the stick.

[canute]

Thanks to all,

 

Tried the paper towel trick for dipstick, as most seem to know (PRM being the exception) it's still difficult to read, also didn't screw dipstick in just allowed for the additional length of threads and deducted from fill mark.

Yep "removed 1.4L, filled with 1.3, removed 1.3 and are still measuring it as overfilled?" 

 

Not sure of the amount 'including cooler' as Beta say refer to PRM handbook, can't understand why they don't state cooler capacity plus PRM quantities? Beta's and PRM's have been in a fairly long term relationship so you'd think that one or the other would firstly provide an easy drain option and comprehensive service instruction with quantities and not forgetting an easy to read dipstick, Ahh utopia! (Tongue in cheek, anyone know why the engine has a brass hand-pump attached to the oil sump?)

 

About to refill (1.3) and run engine in gear to see if levels settle, as suggested.

 

Absolutely no access for removing drain-plug let alone catching any drained oil, I would have to dismantle and remove half the engine room!  

 

Removed oil again, then topped-up, ran engine in gear then checked level, topped-up, ran engine in gear then checked level, Etc, Etc. Not sure if the thing had more oil than required or the extractor wasn't empty, I must be going mad!!! either way hopefully sorted now!

 

Thanks for all the comments.

[Alan de Enfield]

7 minutes ago, canute said:

anyone know why the engine has a brass hand-pump attached to the oil sump?

 

To drain (pump-out) your engine oil as you probably cannot access the sump-plug or get a tray under the engine.

 

The alternative is to get a small electric oil pump and poke a small nylon hose down the dip-stick hole, but you'll never get it all out.

[canute]

The post was about PRM gearbox and the subject of the PRM's sump plug (lack of) access was mentioned, I think you missed the irony in the Tongue in cheek question, anyone know why the engine has a brass hand-pump attached to the oil sump?)

[Tacet]

I think you need to be quite sure that the level.on the gearbox dipstick is being read correctly.  It seems simple enough but it is easy to pick up a misleading smear of oil even when the level is low.

 

You could try sucking on a clear tube poked just below the 'full' level  to see whether oil or air is lifted.

[GUMPY]

33 minutes ago, Alan de Enfield said:

 

The alternative is to get a small electric oil pump and poke a small nylon hose down the dip-stick hole, but you'll never get it all out.

 Beg to differ, my Pela 6000 gets all the oil out of the Yeti and also got all the oil out of the Beta 50 and my PRM gearbox.

Yes I checked the first time by either removing the drain plugs or using the in built pump on the Beta. 😎

[canute]

You could try sucking on a clear tube poked just below the 'full' level  to see whether oil or air is lifted.

 

Excellent idea, I don't know why I didn't think of that myself, I used to use the same method in reverse when topping up WLA batteries, being in a confined space and blind to the electrolyte levels, I used a tube with a cable-tie set on the tube at the optimal level, a gentle blow would either bubble if the height was right or blow air strait through if level was low, in the latter case I would pour a little Distilled/Deionized water down the said tube and then gently blow again, repeating until level was reached. I could do a six bank of batteries in around 1 to 2 hrs. Took 3 days using a dental mirror the first time I attempted.

 

I must clarify before starting further responses, NO specialist top-up bottles and/or other paraphernalia didn't fit in the 200mm or so of space that I had above the battery bank.

 

No suggestions required, I have AGM's now.

 

Regards,

 

[Tracy D'arth]

Some power units have a diverter valve on the drain from the engine sump and the gearbox drain "plugs" to the same brass pump enabling either or both to be emptied.

[Alan de Enfield]

2 minutes ago, GUMPY said:

 Beg to differ, my Pela 6000 gets all the oil out of the Yeti and also got all the oil out of the Beta 50 and my PRM gearbox.

Yes I checked the first time by either removing the drain plugs or using the in built pump on the Beta. 😎

 

You've done better than I - I could never get the pipe to work completely around / thru all the gears on my PRM150.

[canute]

Some power units have a diverter valve on the drain from the engine sump and the gearbox drain "plugs" to the same brass pump enabling either or both to be emptied.

 

Given that Beta recommends the same oil and service intervals on a Beta 43/PRM150 combo a dual pump would be ideal and time saving.

[blackrose]

You're not screwing down the dipstick to check the level are you? It's supposed to measured with the threaded part of the dipstick resting on the gearbox.

 

Apologies if someone has already asked this and I've missed it.

[Alan de Enfield]

30 minutes ago, blackrose said:

You're not screwing down the dipstick to check the level are you? It's supposed to measured with the threaded part of the dipstick resting on the gearbox.

 

That advice seems to be rather at odds with what the PRM manual states - and actually highlights in 'bold'

 

No5 in the instructions for checking your oil

 

 

[cuthound]

1 hour ago, blackrose said:

You're not screwing down the dipstick to check the level are you? It's supposed to measured with the threaded part of the dipstick resting on the gearbox.

 

Apologies if someone has already asked this and I've missed it.

 

You.are supposed to screw the dipstick down fully down to measure the oil level, but this makes getting an accurate reading difficult.

 

@GUMPY showed how to measure the oil level accurately without screwing the dipstick down in one of the posts above.

[Ex Brummie]

If you can struggle once to remove the drain plug, you can replace it with a black iron male elbow and then extend that with a socket and plug. Next time it will be easy.

[Tracy D'arth]

17 minutes ago, Ex Brummie said:

If you can struggle once to remove the drain plug, you can replace it with a black iron male elbow and then extend that with a socket and plug. Next time it will be easy.

But then you loose the advantage of having a magnetic plug, which is the best reason for taking the plug out, to remove any metal particles.

[Ex Brummie]

They will drop to the bottom of the elbow and you can insert a magnet to collect debris. For the number that are 'emptied' with a pump, how do they collect the debris?

[Tracy D'arth]

2 minutes ago, Ex Brummie said:

They will drop to the bottom of the elbow and you can insert a magnet to collect debris. For the number that are 'emptied' with a pump, how do they collect the debris?

Precisely, which is why I will never just suck the oil out. What you find on the magnet tells you the condition of the gearbox.

[Slim]

4 hours ago, cuthound said:

 

You.are supposed to screw the dipstick down fully down to measure the oil level, but this makes getting an accurate reading difficult.

 

@GUMPY showed how to measure the oil level accurately without screwing the dipstick down in one of the posts above.

Don't screw the dipstick in and read the lower line as the full mark.