Arghh..Volvo Penta MS4B gearbox ... No Drive

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oldgit

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Lost drive on port gearbox.
Removing box for inspection today.
Crystal clear oil up to correct level on dipstick.
(Im)possible to repair ?.......rumours of no bits available . :)
Possible to cannibalize parts from a MS5 lurking under my bench ?
Suggestions welcome of what is likely to have broken .....
 
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Your problem is that you dont have out drives.





Sorry - coukdnt help myself, hope you get your issue fixed soon
 
This is from a thread posted last year:

http://www.ybw.com/forums/showthread.php?484025-Volvo-MS4-Gearbox

######

This wouldn’t have happened if you had outdrives.

To check the damper plate is still good you can place it in gear then turn the output shaft by hand , if it locks up it's not the damper plate .turn it both ways in forward and reverse before you remove the box.

If damper plate is ok by turning the shaft both ways in gear it should lock up as it's trying to turn the engine, what you are doing is engaging the cone into the respective gear cup, it it spins both ways there is a problem, could still be gearbox though.
Do this without engine running of course , when I say shaft I mean propeller shaft.

Another test is to take top cover off box, select gear and rotate the big top nut and look if prop shaft turns , this will test the bottom gear set which is in effect a crown wheel and pinion, I've seen the vertical shaft shear many times as there is no splined sleeve as per an outdrive .

######
 
superheat6k said:
Perhaps an Outdrive might suit you better (today at least anyway !). I have written an overhaul manual for the MS3B box. All the bearings and seals will be available, when I rebuilt mine I didn't use any VP supplied parts. I will PM you a link shortly, or will see if I can paste it here.

Here you go ...

https://www.dropbox.com/s/2n3rlh4auna1qbz/Volvo Penta MS3B Gearbox overhaul instructions.pdf?dl=0
Click to expand...

Cheers for that.All printed out.
Box out, dead simple job about an hours work.
Removed coupling end of gearbox box, curiously no bits in oil. .:)
Fork mechanism is moving cone but no drive to the lower gearset, does move fraction then stops.
Assuming something has sheered/stripped or let go on spiral shaft.
Will dismantle a bit more in morning on company time. :).
Do have complete MS5B to pinch bits from, would just swap boxes but gear ratios are different.
2:63 on MS4
1:94 on MS5
 
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oldgit said:
Cheers for that.All printed out.
Box out, dead simple job about an hours work.
Removed coupling end of gearbox box, curiously no bits in oil. .:)
Fork mechanism is moving cone but no drive to the lower gearset, does move fraction then stops.
Assuming something has sheered/stripped or let go on spiral shaft.
Will dismantle a bit more in morning on company time. :).
Do have complete MS5B to pinch bits from, would just swap boxes but gear ratios are different.
2:63 on MS4
1:94 on MS5
Click to expand...

Gear at bottom of shaft It has a plate type clutch inside it .
 
Gearbox in bits ............spiral 853523 shaft snapped. Grr.

MS5 shaft of course different dimensions. Anybody need a spares or repairs complete MS5 B gearbox :)


Contacted Keyparts about new shaft....New shaft on its way from Sweden.
 
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I am enjoying the thread; not your misfortune though. The progress of your investigation is good to read - would love some photos - and to hear how the progress carries on. Would the snapped shaft just be wear and tear or something like clumping a branch or summat round the prop?
 
tillergirl said:
I am enjoying the thread; not your misfortune though. The progress of your investigation is good to read - would love some photos - and to hear how the progress carries on. Would the snapped shaft just be wear and tear or something like clumping a branch or summat round the prop?
Click to expand...

Think this particular gear box started life with about 90-100hp going through it, over the years this increased via 125 HP and 165HP up to the 200HP.
Suspect the boats were getting heavier as well.
Various upgrades appear to have been tried to increase durability of box.
The exterior case looks the same from its first incarnation as MS3 right through seven variations.
Do know the oil cooler was uprated over the years and the lubrication drillings in the shafts look bigger the later the model.
As an aside, several boats in our club have these poxy gearboxes, it you will be amazed to learn that most of them have a spare gearbox tucked away somewhere.
The most recent failure in club members Princess 33 resulted in two brand new Hurth 75A gearboxes being fitted,this was because the totally destroyed reduction gear is no longer in production.
I actually feel lucky today...what ever your whinges about Volvo Penta, try getting a major OME bit for a 30 year old engine from anybody else, off the shelf :)
 
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Might be useful if my MS3B manual could have an addendum to show MS4 / 5 differences. Clearly a need for an explanation of these boxes for future users.
 
Your manual was most useful, imagine a lot of time and effort went into producing that.
Fortunately the workshop next to me houses an outfit which repairs todays super whizzy auto gearboxes and the old clunk box which was taken round to them provoked a few wry smiles, think the word
"Stone Age" was mentioned.

The obvious differences so far....
Just for starters the bearing "journals" ? on the MS5B spiral shaft are about 1.5mm greater in diameter than the MS4B. Completely different bearing set.
The spiral gear ratio on shaft is def. different as well.
Oil drilling is smaller on later shaft. !!! Presumably to keep more metal in shaft.

Did wonder briefly about getting the shaft turned/ground down but told this would destroy the case hardening and that way lies madness apparently .:)
At this point decided it was waste of time trying to mix match the two boxes.

Rang KeyParts, they contacted Sweden who announced they had stock and quoted me price with bit of discount.
The Bill......Not sure if I bought a 300mm bit of case hardened steel or most of Sweden. :)


earlier and later shafts, rubbish pix but very different size drilling for oil lubrication channel
 
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oldgit said:
Your manual was most useful, imagine a lot of time and effort went into producing that.
Fortunately the workshop next to me houses an outfit which repairs todays super whizzy auto gearboxes and the old clunk box which was taken round to them provoked a few wry smiles, think the word
"Stone Age" was mentioned.

The obvious differences so far....
Just for starters the bearing "journals" ? on the MS5B spiral shaft are about 1.5mm greater in diameter than the MS4B. Completely different bearing set.
The spiral gear ratio on shaft is def. different as well.
Oil drilling is smaller on later shaft. !!! Presumably to keep more metal in shaft.

Did wonder briefly about getting the shaft turned/ground down but told this would destroy the case hardening and that way lies madness apparently .:)
At this point decided it was waste of time trying to mix match the two boxes.

Rang KeyParts, they contacted Sweden who announced they had stock and quoted me price with bit of discount.
The Bill......Not sure if I bought a 300mm bit of case hardened steel or most of Sweden. :)


earlier and later shafts, rubbish pix but very different size drilling for oil lubrication channel
Click to expand...

Think I’ll have one in my used stock .
 
Cant believe after moaning about outdrives for so long, you bought a boat where the gearbox is pretty much the same as an outdrive!

My golden rules for boats, no wooden boats, no american boats, no outdrives and no poxy volvos!

Hope you get sorted soon!
 
Parabordi said:
Cant believe after moaning about outdrives for so long, you bought a boat where the gearbox is pretty much the same as an outdrive!

My golden rules for boats, no wooden boats, no american boats, no outdrives and no poxy volvos!

Hope you get sorted soon!
Click to expand...

mea culpa........but at least it can be fixed IN the water....sigh

Drowning sorrows in clubhouse last night and somebody said...You think have problems !
Invited me to look in the boot of his car,gearbox from Princess 410 lurking inside.
Drive shaft destroyed taking a few bits with it,estimate to get sorted £4,500 + VAT.
Ended up buying new box
 
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oldgit said:
mea culpa........but at least it can be fixed IN the water....sigh

Drowning sorrows in clubhouse last night and somebody said...You think have problems !
Invited me to look in the boot of his car,gearbox from Princess 410 lurking inside.
Drive shaft destroyed taking a few bits with it,estimate to get sorted £4,500 + VAT.
Ended up buying new box
Click to expand...

Wouldnt be volvo by any chance?
 
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