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Central flex coupling


bigcol

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Please see photo

im relying on others at the moment, as just had a knee replacement last week, and if you had one you know what I’m going through. Pain and more pain.

 

whilst I was away the engine beta 90 which came to me via the forum was placed in position 

as you can see it fits, but too high to conect to driveshaft.

somone says you can buy a flexible coupling, is this wishful thinking.

i hope I can find somthing if not the engines got to come out again

 

any sugestions, or is it engine out and lower mountings, slimline mountings?

363A4463-D42D-47DD-B553-862B0476DBDC.jpeg

A03503DF-7A18-43FB-85CA-96616A11A20B.jpeg

1E92DCC0-C419-4824-BD71-29AAC83A533B.jpeg

05345988-35E1-4CB0-8A6E-5C36CA86D70E.jpeg

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9 minutes ago, bigcol said:

Please see photo

im relying on others at the moment, as just had a knee replacement last week, and if you had one you know what I’m going through. Pain and more pain.

 

whilst I was away the engine beta 90 which came to me via the forum was placed in position 

as you can see it fits, but too high to conect to driveshaft.

somone says you can buy a flexible coupling, is this wishful thinking.

i hope I can find somthing if not the engines got to come out again

 

any sugestions, or is it engine out and lower mountings, slimline mountings?

363A4463-D42D-47DD-B553-862B0476DBDC.jpeg

A03503DF-7A18-43FB-85CA-96616A11A20B.jpeg

1E92DCC0-C419-4824-BD71-29AAC83A533B.jpeg

05345988-35E1-4CB0-8A6E-5C36CA86D70E.jpeg

You might just get an Aquadrive or Python drive in the gap. Both have double Constant velocity joints.

Edited by bizzard
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17 minutes ago, bigcol said:

Please see photo

im relying on others at the moment, as just had a knee replacement last week, and if you had one you know what I’m going through. Pain and more pain.

 

whilst I was away the engine beta 90 which came to me via the forum was placed in position 

as you can see it fits, but too high to conect to driveshaft.

somone says you can buy a flexible coupling, is this wishful thinking.

i hope I can find somthing if not the engines got to come out again

 

any sugestions, or is it engine out and lower mountings, slimline mountings?

363A4463-D42D-47DD-B553-862B0476DBDC.jpeg

A03503DF-7A18-43FB-85CA-96616A11A20B.jpeg

1E92DCC0-C419-4824-BD71-29AAC83A533B.jpeg

05345988-35E1-4CB0-8A6E-5C36CA86D70E.jpeg

I was going to suggest an Aquadrive or Pythondrive but it there might be too much displacement even for them.

https://www.walterscheid-group.com/wp-content/uploads/Aquadrive_Cat_2018_GB-1.pdf

 

Edited by Flyboy
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Are you mounting the engine on rubber flexible mounts? Personally on a boat that size which would absorb a lot of noise, I would lower it right down dead level and mount it solid to the bearers and achieve perfect alignment without the need for expensive couplings. You will also avoid all the problems that rubber mounts might give, like collapsing and whatnot, coming undone.

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I have seen an Aquadrive running at that amount of displacement but cannot advise it, they are designed to run slightly misaligned, not at a big angle.

 

It should not be a massive job to lower the engine, an hour with a gas axe and a welder would see it done.

 

There is no photo of the engine mountings so its impossible to say if it would be easy or not. The PRM gearbox is a dropbox already.

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That's one helluva big offset. I agree with the others, the offset needs reducing or the engine moving forwards by a foot or two to get the space to fit a pair of CVJs  and short driveshaft.

 

The engine looks to be offset to one side too from the photos... is it? Very odd if it is...

 

 

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2 minutes ago, Mike the Boilerman said:

 

That's one helluva big offset. I agree with the others, the offset needs reducing or the engine moving forwards by a foot or two to get the space to fit a pair of CVJs  and short driveshaft.

 

The engine looks to be offset to one side too from the photos... is it? Very odd if it is...

 

 

I think its just been lowered there roughly where its going.

Edited by bizzard
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There does not appear to be any thrust bearing on the tail shaft,  so the gearbox will be taking the thrust (this is OK).  The engine mounts must  to be designed to handle the thrust, as should any drive shaft between the tail shaft and the gearbox flange.

N

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23 minutes ago, BEngo said:

There does not appear to be any thrust bearing on the tail shaft,  so the gearbox will be taking the thrust (this is OK).  The engine mounts must  to be designed to handle the thrust, as should any drive shaft between the tail shaft and the gearbox flange.

N

 

Thats a very good point, and I never like to see rubber engine mounts when there is no propshaft thrust bearing, as the prop thrust is transmitted to the boat only via the flexible rubber mounts which are quite capable of breaking. 

 

 

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I think you're going to have to move the engine more into line but if you can afford it I would seriously consider fitting an Aquadrive, apart from anything else it's going to save you the headache of getting the alignment spot on.  It looks like there's enough room but you will nee to weld/bolt on a thrust plate, I'd speak to Nick or Steve at TW Marine.

 

If it's too expensive ( and bear in mind if you have to pay someone to sort out the alignment that could be a lot of hours labour) I'd agree with Bizzard - solid mount it then at least once it's done it's done. 

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Yes your right engine was just dropped in.

it hasn’t been centralised.

the mounts are quite tall

There is some more pics, but will try and make them smaller

and yes I agree that the easiest way would be to drop the engine down, but talking to welders it will always be a job and a half lol

i can’t see it be a major properly, but wish someone would do it while I’m laid up.

i hate it when all you hear is problems, solutions is what we wasn’t to hear 

 

9B3668AE-7A3F-4823-9339-DE9DE1AD5113.jpeg

 

 

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Edited by bigcol
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Looks to me as though the engine bearers are a bit too close together. At least, you need to shuffle the engine around until the engine mounts are properly standing on the bearers if possible, then re-assess the resulting offset. And move the engine forwards if you can. More length in the gap reduces the angle of the offset and increases the space for the intermediate propshaft, and helps is all manner of ways. 

 

 

 

 

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16 minutes ago, bigcol said:

Yes your right engine was just dropped in.

it hasn’t been centralised.

the mounts are quite tall

There is some more pics, but will try and make them smaller

and yes I agree that the easiest way would be to drop the engine down, but talking to welders it will always be a job and a half lol

i can’t see it be a major properly, but wish someone would do it while I’m laid up.

i hate it when all you hear is problems, solutions is what we wasn’t to hear 

 

 

 

 

67545982-654F-4367-B6BD-F309C9C05FF0.jpeg

89A7A33F-522F-4979-8B13-393C82732849.jpeg

 

You may be able to lower the engine by having some new brackets made up (4 off).  Forum member Kedian would probably be able to help.

http://www.kedianengineering.co.uk/index.html

Edited by Flyboy
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I think the lower adjusting nuts are still on the engine feet so if you can lift/jack the engine to take the lower nuts off it will probably drop bu half and inch and that would be a lot better but only if you go for an Aquadrive. I think they come in various lengths so get the engine as far forward as sensible to lessen the angle.

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Remove the 4 brackets from the engine they are bolted on.

Carve the tops of the brackets.

Build up the brackets by welding steel on 3 sides by as much as you need to drop the engine to get it in line and weld the tops back on.

 

Can all be done off the boat at a welders once you have measured how much drop you want.

 

Are you certain that the engine will fit down in between the engine beds?

Edited by Boater Sam
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3 minutes ago, Boater Sam said:

Carve the tops of the brackets on the engine.

Build up the brackets on 3 sides by as much as you need to drop the engine to get it in line and weld the tops back on.

 

Can all be done off the boat at a welders once you have measured how much drop you want.

 

Are you certain that the engine will fit down in between the engine beds?

 

That's an excellent point. I think it may not and if it will it may be so close to the bed there is a good chance of vibration noise where it bangs on the bed.

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1 hour ago, Tony Brooks said:

I think the lower adjusting nuts are still on the engine feet so if you can lift/jack the engine to take the lower nuts off it will probably drop bu half and inch and that would be a lot better but only if you go for an Aquadrive. I think they come in various lengths so get the engine as far forward as sensible to lessen the angle.

I see what you mean, I unable to get down their, so relying on mates etc.

but if the thread inside the mounts can be reduced I think that could get me in the right direction!

54 minutes ago, Boater Sam said:

 

 

Remove the 4 brackets from the engine they are bolted on.

Carve the tops of the brackets.

Build up the brackets by welding steel on 3 sides by as much as you need to drop the engine to get it in line and weld the tops back on.

 

Can all be done off the boat at a welders once you have measured how much drop you want.

 

Are you certain that the engine will fit down in between the engine beds?

Still might not come to that fingers crossed but another good idea!

theres a good 4 inches below oil pan and bottom of boat

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2 hours ago, bigcol said:

 

theres a good 4 inches below oil pan and bottom of boat

I should hope that there is! This must be  a very shallow draught hull with a tiny prop.

 

A thought, that PRM box is a"D" something meaning "drop"is it not? What is the type number on the label?  Like 160D2 or 260D2?

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13 minutes ago, Boater Sam said:

I should hope that there is! This must be  a very shallow draught hull with a tiny prop.

 

A thought, that PRM box is a"D" something meaning "drop"is it not? What is the type number on the label?  Like 160D2 or 260D2?

I will have a look tomorrow, all I know its8 years old but only done 440hrs, bought through a member of this forum. Got a large 4 bladed prop

Edited by bigcol
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