YSM8 engine alignment and ??

[Bob_S]

Hello All...
I was hoping some of you could help me identify this beige part / spacer thing in my drive train. The engine is a YSM8 in a CD27. Lately I've been feeling like there's more vibration then usual when I'm in gear. I have a brand new cutlass bearing, installed this season. The prop and shaft were balanced at the same time. I was thinking engine alignment? Most of the articles I've seen on how to fix that discuss matching the plates of the engine power take off and the head of the shaft..measuring all around to make sure there are no uneven gaps. (as I understand it) Anyway, I have this "thing" (spacer) between the power take off and the shaft plate...trying to figure out how that fits into the alignment plan...
Thanks for any advice, anecdotes etc...you might have
Best regards,
Bob S.
'81 CD27 - #212

[mgphl52]

The "spacer" is typically called a drive saver, or some such. It is supposed to "break" before your reverse gear breaks if something jambs your prop.
To align everything, you will need to remove the drive saver and slide the shaft forward so you can measure any gaps and/or alignment issues.
Also note the alignment must be done with your boat in the water.

[wikakaru]

The DriveSaver brand coupling looks a little different than what you have. The one you have looks like a PYI Flexible Shaft Coupling:
https://www.pyiinc.com/flexible-shaft-couplings.html

The PYI web site has instructions on how to check the alignment.

Smooth sailing,

--Jim

[Bob_S]

Thanks guys - that helps point me in a direction. The to do list just got even longer..
Best to all,
Bob S.

[fmueller]

Bob ...

About YSM engine shake ... when I bought my 27 I was pretty worried at how much vibration there was. I had a mechanic have a look at it. This was in Belfast ME. He said to me " theys good news and theys bad news ... good news: engine will run forevah ... bad news: engine will run forevah".

The guy was a riot actually ... he had world class plumber butt and I'll never forget "the view" of him cramming himself over the engine to take a peek at the drive shaft. He also said - "You know what these ahh don'cha ? This iz justa rice paddy pump. You ahh suppostah to staaht her up, walk away, come back ten yees latah, staahp her , rebuild her, staht her up, walk away again."

As god is my witness ...

good luck

[Bob_S]

LOL Hello and thanks Fred - great story!
I did research the engine a bit before I bought the boat and read one of it's design purposes was in fact to run irrigation pumps I probably shouldn't jinx it but it has run very reliably so far. It might just be me being overly cautious. One of these days I'd like to hitch a ride on someone else's 27 with the same engine so I can compare..
Best Regards,
Bob S.

[fmueller]

Bob,

I actually did replace my YSM a few years ago ... mine was fine actually except I think the centrifugal throttle control must have been worn somehow and in certain circumstances the motor would just slowly slow down and finally stop no matter throttle position. 30 minutes later I could start it right back up and then it might run fine for months, but then just do that again. I replaced all the fuel components except the injector. I flushed the tank as best I could. This would happen 2-3 times a season. At one point someone told me it was a carbon occluded up mixing elbow, so I replaced that and the engine did run a little better, but then it did it again. I finally decided I had to get a new mill.

It wasn't burning oil, and started up easily. And while I appreciate the extra power I have now, the YSM pushed my boat around ok and I just lived with the noise (there were certain RPM points where the engine was smoother). Fuel economy was pretty amazing. So if yours doesn't quit on you you are probably ok ... They just shake a lot.

[csoule13]

Another CD27 with a YSM8 here. Can't speak to transmission alignment, but did just have all four engine mounts replaced, and the engine aligned at the same time. I wouldn't call it a smooth ride, but certainly a noticeable improvement. Old mounts were basically concrete at this point, and the alignment was less than satisfactory.

Agree w/ the previous comment that there are just some RPMs that things seem a little smoother at.

[Bob_S]

Thank you guys - it's comforting to know there's company out there haha. I thank goodness for this site these days. Someone else suggested a three blade prop as opposed to the two blade I have...Any thoughts?
Cheers!!
Bob

[mgphl52]

Someone else suggested a three blade prop as opposed to the two blade I have...Any thoughts?
Cheers!!
Bob

You do get a little bump when both blades move between dead-wood and water. But changing the prop, IMO, depends on how you sail.
When I bought KAYLA back, I switched from the 3-blade Michigan wheel to a 3-blade Campbell Sailor. During the time I use to race KAYLA, the Michigan prop would drop speed by at least a full knot when locked in reverse vs freewheeling. And, Yes! at 4+ knots it would spin quite well! The Campbell, however, has no difference between locked or free and I've never heard it spin.

So, if you keep your 2-blade, just mark the shaft for where the blades are behind deadwood for best sailing and put up with a bit of vibration.