Removal / Fitting Duoprop

Tafflad

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Oct 23, 2007
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I have changed props many times, always set to correct torque, now have DuoProp.
Removing rear prop straight forward, and aware of tool required to remove front prop nut.
However the official VolvoPenta tool 3862797 appears to be a T-bar tool.
As they specify a torque, does the tool also take a square drive bit for a torque wrench.?

Anybody made one of these ? or know where I can get dimensions ?
 

alldodge

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Don't know the dimensions
I set my elbow for torque on props, and never had one loosen or come off
 

Tafflad

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The price of these stainless Steel duoprops, plus with no lock pin of tabs .... I want to set it right.
 

dypcdiver

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Taff, I have been using a piece of 2"ID pipe that I put 3 slots in, and then screwed into a reducing bush, then 4" of 1" pipe with a 30mm AF nut welded that can then be slacked and tightened with a 30mm socket. a few welds on the pipe threads on the reducing bush allows slacking and tightening and the use of a torque wrench.
 

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bruceb58

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I made my own tool. Basically bought some tube of the correct diameter, cut some slots in it and then welded a 1/2" socket on the end of it.

I will see if I can locate a picture. Pretty sure I gave the tool to the guy who bought my boat last January.
 
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Tafflad

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Taff, I have been using a piece of 2"ID pipe that I put 3 slots in, and then screwed into a reducing bush, then 4" of 1" pipe with a 30mm AF nut welded that can then be slacked and tightened with a 30mm socket. a few welds on the pipe threads on the reducing bush allows slacking and tightening and the use of a torque wrench.
Thnx
 

Tafflad

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T
I made my own tool. Basically bought some tube of the correct diameter, cut some slots in it and then welded a 1/2" socket on the end of it.

I will see if I can locate a picture. Pretty sure I gave the tool to the guy who bought my boat last January.
That was the reason for the post .. I don't know what the correct diameter is
 

bruceb58

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T

That was the reason for the post .. I don't know what the correct diameter is
Pretty easy to figure it out with some calipers...that's what I did. I believe I still have a piece of the pipe but can't remember if it was for that project or not.

You could also buy the Volvo tool and modify it by welding on the socket. Of course that is much more expensive.
 

Tafflad

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Pretty easy to figure it out with some calipers...that's what I did. I believe I still have a piece of the pipe but can't remember if it was for that project or not.

You could also buy the Volvo tool and modify it by welding on the socket. Of course that is much more expensive.
I don’t have access to boat at moment, looks like I’ll just have to wait.
 

Tafflad

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Gents ... I have today been able to get my hands on the tool and measure it .... In case anyone else has the same need in future I attach a simple sketch and dimensions.Prop Tool.jpg
 

bruceb58

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That makes sense to me. I had two pieces of thick walled tubing in my shed. One of the pieces is 2 3/8" OD with 2" ID. ID is what matters obviously.

That must have been the one that I made my tool with.
 

Tafflad

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Thinking a standard scaffolding tube me be my option ….. will need to take rear prop off first so I can check mine ID that could be used.
Standard scaffolding is 48.3mm and a 3.2mm - 4.0mm wall thickness.

getting a tube with 2” ID in Europe not going to be easy
 

Scott06

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Thinking a standard scaffolding tube me be my option ….. will need to take rear prop off first so I can check mine ID that could be used.
Standard scaffolding is 48.3mm and a 3.2mm - 4.0mm wall thickness.

getting a tube with 2” ID in Europe not going to be easy
DN 50 pipe should be really close to 2” ID
 

Tafflad

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Managed to get some EN50 pipe, from a friend ... he even turned down a portion of it to match the dimensions of the VP tool.
I'll cut notches tomorrow, and weld on a 30mm nut on the rear.

Simple Q ...... assuming front prop (inner) is left hand threaded nut, and rear prop (outer) is right hand threaded nut.
As there is no locking tab washer or split pin .... what keeps the nut from working loose ? Particularly the rear (outer prop) nut.
 

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alldodge

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Pretty sure u will find that both are RH threads. Merc is held only by the taper of the nut and the torque
 

Tafflad

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Pretty sure u will find that both are RH threads. Merc is held only by the taper of the nut and the torque
OK … assumed different threads as in this video the guy goes to pains to explain having gearbox in forward for 1 prop and reverse for the other.
 
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