Hey Spareparts

[cfelton]

It rattles anything light laying loose in the boat like a fishing rod laying up against the gunnel. Its really not terrible but definately noticeable to me and others in or out of the water. It makes my old Ritchie compass spin around. But after I get underway I trim the drive up till the bow almost bounces and it goes away. My buddys 86 v20 with the same motor and drive is smooth as silk all the time. If I can get over Christmas I might buy me a new coupler and change it out. I dont think it will be to bad of a job. I think I can do it without pullin the motor out, just support the rear , pull the outdrive and crawl back there and unbolt it. Probley gotta pull the bellhousing off.

[spareparts]

pull the drive and make sure you don't have one of your u-joints binding, while you have the drive off, try the alignment shaft/engine running trick

[cfelton]

Ive checked the u joints, the're new and move freely. Ill try the alignment tool,wobble thing when I pull it next time. Thanks Spare!

[cfelton]

Well, I found my vibration! I went to check the alignment on my 170 Merc/ Alpha one drive yesterday and I reached in and grabbed the drive shaft and can shake it all around. So my coupler is shot! I ordered one last night, 226.00 with shipping. Maybe this will take care of the vibration I've been feeling since I rebuilt the motor and drive. Seems its always something! This is the ONLY thing I havent replaced!!!! Will probably take a good day ta pull the motor and drive and get it in. Gotta get it right really quick, we are headed to Nags Head in 2 weeks!! Cant wait, We need a good vacation!!

[THEFERMANATOR]

The couplers on those are known to fail, aftermarkets are readily available for them.

[steplift20]

just my 2 cents
hows the prop is it bent or damaged look at it maybe thats the problem

[cfelton]

The prop is a new stainless prop, with no signs of damage and it vibrates in neutral ,on the hose , sittin in the yard . Ive almost ruled the drive and prop out. I can reach over and behind the motor and grab the drive input shaft and shake it around inside the coupler, so im thinking thats gotta be the culprit. This old 77 V has alot of room around the back of the motor but I think Ill just pull the motor completely out ta change out the coupling. Looks like I gotta pull off the engine bellhousing to get at the coupling bolts and ta get it out of the bellhousing hole. It won't be to bad of a job being I already had it out before. Probably can do it in a day (I hope).Thanks for all the info fellas! Ill let you all know how it turns out.

[spareparts]

if you can move teh drive shaft like that, I would have to agree that its teh coupler, most of yhe boats i work on you can't get back behind there. Double check the gimbal bearing while you have the drive off

[cfelton]

Will do!!! I replaced it when I rebuilt it but Ill check it out good when I pull the drive. Thanks again!!