Westerly Pentland Propshaft tube

[geoffatstanpit]

A friend who hasn't yet figured out how to get into this forum has the following question. Answers will be forwarded.

"I have a problem !
I want to replace the Rubber Tube that connects the stern tube to the
stuffing box on my Westerly Pentland.
At this time I have been unable to remove the main shaft coupling.

so any ideas for :-
1) How to replace the old Rubber tube (1979) without having to remove
the coupling ?
2) How to get the coupling off. The 3 socket Allen bolts in the
coupling will not budge !"

All suggestions appreciated.

Geoff

 

[VicMallows]

I can't see that it's possible without releasing the shaft at the engine end so as to be able to withdraw the shaft. It's not the coupling he needs remove, but the shaft from the coupling. Has he soaked everything in releasing oil (beter than WD40) and left it a few days? 3 bolts sounds strange?

Vic

 

[pvb]

Is it the Volvo coupling?

I used to have a Pentland. If your friend has a Volvo engine and shaft coupling, it probably has 6 Allen bolts (3 each side) and looks like the item in the middle of the top row in the picture below. The way to shift these bolts is first to soak them with penetrating oil for a while, then to use a socket-type Allen key with a torque wrench. You sometimes find that even after loosening the bolts, the shaft is still difficult to shift. In this case, remove all the bolts completely, then refit the rearmost 2 bolts backwards (ie screw them in to the tapped hole first). Put a couple of thin strips of steel in the slots each side of the coupling, then tighten the bolts evenly on to the steel strips - this will gently prise open the coupling enough to remove the shaft.

 

[VicMallows]

Re: Is it the Volvo coupling?

A man who's been there and done it!.

Now please tell me how to shift the gearbox output flange nut on my BUKH 20.
(30mm staked nut). Have tried with 2-foot lever wrench and holding bar. I would love to change the rear gearbox oil seal.

Any help VERY much appreciated!

Vic

 

[pvb]

Bukh gearbox nuts...

Sorry, Vic, I've no direct experience of Bukh engines, so I can't offer any magic words of advice. Have you "unstaked" the nut, or are you just hoping it'll unstake itself? Is it a normal right-hand thread, or a left-hand thread? There was a post last year about changing Bukh gearbox seals - might be worth sending a PM to a couple of those guys and see what they say.

 

[VicMallows]

Re: Bukh gearbox nuts...

Hi pvb,

Many thanks for that link. I see posts were when I was on holiday last year (supposed to get to Scilly, but had enjoyable time in Poole!). Obviously I need to use the 'search' function more.

I am assured that it is a 'normal' (RH) thread (YANMAR has a LH thread). Have not yet unstaked the nut due to access difficulty. Several people have said it should break free easilly, but maybe I have an awkward one; will probably try to drill the nut.

Vic

 

[Ruffles]

Re: Is it the Volvo coupling?

Isn't there a roll pin in the coupling as well? This needs to be removed with a punch of a certain size.

Rob.

 

[pvb]

Roll pin...

Roll pin isn't normally fitted in the Volvo shaft coupling, although it's always possible that someone may have fitted one as a "belt and braces" measure.

 

[philip_stevens]

Re: Is it the Volvo coupling?

Vic,
have you got a workshop manual? If not, I can scan and send you the "gearbox" pages you need if you can explain exactly where this nut is.

 

[Thistle]

Re: Is it the Volvo coupling?

[ QUOTE ]
In this case, remove all the bolts completely, then refit the rearmost 2 bolts backwards (ie screw them in to the tapped hole first). Put a couple of thin strips of steel in the slots each side of the coupling, then tighten the bolts evenly on to the steel strips - this will gently prise open the coupling enough to remove the shaft.

[/ QUOTE ]
It's great how reading these forums helps! This advice was exactly what I needed today and it worked a treat.

Many thanks, PVB

 

[geoffatstanpit]

Re: Is it the Volvo coupling?

My friend thanks you all especially pvb. I think he will be joining us when I've shown him how to work it.

Geoff

 

[citygirl345]

Re: Is it the Volvo coupling?

Came across this thread as I'm in the process of changing the rubber tube on my (1979) pentland with MD11 Volvo.

The 3 Allan capscrews on my coupling hold the coupling to the gearbox flange - they were undone with a long allan key & length of conduit as an extension. You need to put a block between one of the bolts & sutable point on the engine bearer / hull or you just turn the engine over.

The coupling is secured to the shaft with a taper pin driven in from one side. Mine would not shift until dot punched & drilled. Fortunately the pin is relatively soft. This arrangement is original to the boat & referred to in my Volvo engine manual. The shaft is also keyed. The coupling needed a decent hydraulic puller to shift it.