Shakey in gear

[S/V Sideways]

Please advise.
I'm looking for a device to rectify a misalignment issue between the transmission and the shaft flanges. I can only get it to + - .015" and the motor shake's when I put it in gear while tied up in my slip. Checked the wheel, checked the cutlass and checked the shaft, all kosher.
Already replaced the motor mounts.
Any information will be appreciated

 

[dlochner]

You will have to patiently adjust the mounts to get the alignment correct. A tedious job, but necessary.

 

[S/V Sideways]

Nah, no more patience for that, spent a full week and I've signed off on alignment. I'm looking for a misalignment flange, coupler device. Thanks for the input tho.

 

[kloudie1]

Welcome to the forum!
Could be an out of balance propeller as well. ?

 

[S/V Sideways]

Could be. I did dive on it and didn't see any signs of hitting anything or picking up a trap or rope, no play in the cutlass bearing that I could feel.
Probably need to pull it off, start the engine and put it in gear. But that might not be a very good test for the amount of effort involved. I'm sure not having the resistance from the wheel turning against water would sully such a hail Mary play. Thanks for the suggestion tho.

 

[dlochner]

You could try something like this product from PYI. It might work if you have room for it and if it doesn't affect other parts of the drive train.

PYI Inc. | Flexible Shaft Couplings

The R&D Marine Flexible Coupling fits between the transmission output flange and shaft coupling. It is designed to protect a boat's drivetrain.

www.pyiinc.com

 

[S/V Sideways]

Hello again, thanks for the link. I've been in touch with that company/Isoflex products and they are a viable alternative. The rep told me $376 for the one I could try. I will try that product if I can't find an actual misalignment coupler.
I'm thinking I need more of a CV joint type of product.
I explained to the rep what was happening and he said that their products are more for slight vibration.
Thanks

 

[Davidasailor26]

You might be looking for an Aquadrive - Welcome to Aquadrive . Although I’m sure that’s not the inexpensive route, and it requires a cross brace that can carry the engine’s thrust instead of the motor mounts.

 

[JoeWhite]

Are there zinc attached to the shaft? If they are worn out, remove them then try. Requires a dive

 

[JamesG161]

Sounds like you have a transmission issue.

Model of Engine would help.

Jim...

 

[S/V Sideways]

1004-42 series Perkins

 

[S/V Sideways]

Davidasailor26 thanks that is more along the lines of what I'm looking for.

 

[Hayden Watson]

You might check out the Sigma Drive from Brunton which will accommodate up to 3º out of alignment. They are the makers of AutoProp.
The Sigma Drive does not require a thrust bearing and takes up no more room than a conventional coupler and bolts to the transmission flange without modifications. I have heard good things about them and have a friend who is currently on the hard for a bottom job and will install one on his Catalina 30. He will be letting me know what he thinks in the next couple of weeks.

 

[Ralph Johnstone]

I can only get it to + - .015"

I don't know if you'll find much on the market that can live with that much misalignment. Quite likely one or two other problems other that the mounts causing your misalignment . I'm afraid it's back to the knuckle buster all over again to try to trim that down or find out what is preventing a successful alignment.

Is that ± 0.015' radial or angular ? Don't be offended, but very few people know the first thing about shaft alignment (read some of the previous offerings on this site) unless they've done some serious reading. The attachment below is a pretty good procedure. I use a trimmed down version of it for checks (after you know what you can trust) and every 5 - 10 years might realign to remove one or two thou. to keep it below 0.001" / inch of flange diameter.

 

[S/V Sideways]

You might check out the Sigma Drive from Brunton which will accommodate up to 3º out of alignment. They are the makers of AutoProp.
The Sigma Drive does not require a thrust bearing and takes up no more room than a conventional coupler and bolts to the transmission flange without modifications. I have heard good things about them and have a friend who is currently on the hard for a bottom job and will install one on his Catalina 30. He will be letting me know what he thinks in the next couple of weeks.

Thank you!
I will contacting them tomorrow

 

[Hayden Watson]

When you say + - .015", do you mean that it is a vertical offset or an angle misalignment. To put it another way, are the output shaft and the prop shaft parallel to each other but offset by 0.015" or when you measure the gap in the flange, is face tight on one side and has a 0.15" gap on the other. Assuming that the flange is 4"ø that would mean that the shaft is 0.21º out of alignment. The spec's call for this gap to be 0.003", a gap of 0.015" would be 5-times more than it should be. The Sigma drive I linked to can go to 3º.

 

[Hayden Watson]

When you say that you can only get 0.015", why is that. There are only a few reasons why you cannot get alignment that I can think of and it would be good to resolve the root cause first. The artical that Ralgh linked to is an excelent resourse. In figure 1 it shows the three main causes. When I bought my boat, the shaft was bent as shown on figure 1B and I could not get a good alighment because of that. 1C coupling not square can be fixed if the shaft is not bent by getting a Fit and Face on the coupling by a machine shop.
If the shaft and coupling are good and your misalignment is like shown in figure 1A, you should be able to get it fixed unless your motor mounts cannot be adjusted.

 

[S/V Sideways]

When you say + - .015", do you mean that it is a vertical offset or an angle misalignment. To put it another way, are the output shaft and the prop shaft parallel to each other but offset by 0.015" or when you measure the gap in the flange, is face tight on one side and has a 0.15" gap on the other. Assuming that the flange is 4"ø that would mean that the shaft is 0.21º out of alignment. The spec's call for this gap to be 0.003", a gap of 0.015" would be 5-times more than it should be. The Sigma drive I linked to can go to 3º.

Angle misalignment

 

[dlochner]

Angle misalignment

Has the shaft and coupling been fit and faced?

 

[S/V Sideways]

Has the shaft and coupling been fit and faced?

Great question! I have no idea, have never met the last owner, purchased the boat from a broker.. trust me when I say that the alignment issue isn't the only situation I'm dealing with.. There is a yellow legal pad full of projects that need to be done on this 45 year old Morgan. And I highly doubt the previous owner (who gave up after 6 months) would be of any technical assistance or have any answers for me on why this boat is in the shape it's in. It's basically been used as an apartment for years.