Grand Banks 36 single screw

[shaun 36]

Hi everybody, my name is Shaun and I have a question. I have a grand Banks 36 single screw removed the shaft and found a cutlass bearing halfway up the shaft. I understand there is a cutlass bearing at the top of the shaft and at the bottom of the shaft, but is there a third? How many cut bearings on a single screw ground 36 I look forward to your replies thank you Shaun.

 

[O C Diver]

Generally there is a cutlass bearing at the propeller end of tube or bearing holder. Usually there isn't one at the transmission end as either the transmission or shaft seal act as the bearing. Usually a cutlass bearing in the center of the tube means the rear cutlass bearing moved up the tube. Think the middle one in your tube isn't there by design.

Ted

 

[Comodave]

Welcome aboard.

 

[Mainecoast]

Hi everybody, my name is Shaun and I have a question. I have a grand Banks 36 single screw removed the shaft and found a cutlass bearing halfway up the shaft. I understand there is a cutlass bearing at the top of the shaft and at the bottom of the shaft, but is there a third? How many cut bearings on a single screw ground 36 I look forward to your replies thank you Shaun.

If there is one up in there, you'd have to pull the shaft tube to get to it. And I don't know what exactly that would entail. You'd have to drop the rudder to get it out of the way. I have the same boat and it would be a pretty big job...

 

[shaun 36]

Thanks guys. I would love to know if anybody out there has ever removed the shaft log on a single screw Grand banks 36 my main question is is it a two-piece with the coupling in the middle for the cutlass or continuous piece to the housing? Plus, method of removal would be good to know thanks guys. Really appreciate your time.

 

[GB32Seattle]

Hi everybody, my name is Shaun and I have a question. I have a grand Banks 36 single screw removed the shaft and found a cutlass bearing halfway up the shaft. I understand there is a cutlass bearing at the top of the shaft and at the bottom of the shaft, but is there a third? How many cut bearings on a single screw ground 36 I look forward to your replies thank you Shaun.

Here are a couple of drawings for you. I have a 32 woodie and it shows 3 bearings. The stern tube is threaded in two sections. The center bearing held in place with set screw(s)

 

[SteveK]

My GB36 had two struts, add the tube makes three

 

[mbdana]

Shaun, very interesting that you bring this up. One year ago we determined that we needed to replace the cutless bearings on our 1988 single engine engine (CAT 3208NA) 36' GB Classic. Knowing I was not going to do this in my driveway I was, finally able to find a yard that would do it. (After contacting 15). Originally the yard was going to only replace the lower...I mentioned the upper would have similar wear and should be replaced. In the mean time, I contacted the previous owner who told me that he thought there were 3 bearings that he replaced in 2007. I mentioned that to the yard, they said no and the GB drawing I had, showed only two (circa 1974). My shaft is 2" x 17' so I thought it plausible to have 3 but I went along with the boatyard to replace two.

While removing the shaft to replace the 2 cutless bearings, the shaft tube came out with it. The boat yard notified me and told me that that shouldn't have happened but will be no problem. I asked if that was caused by an unknown third cutless. They said no.

When all was said and done, I received 2 new cutless bearings, stern tube/shaft tube was reinstalled and re-bedded, New shaft seal, Rudder repacked and new engine mounts to enable proper alignment. (My suggestion)

Based on the length of my shaft (17') the amount of shaft ahead of shaft seal to tranny and the tail beyond the lower cutless, there would be about 11' of shaft (2") between cutless bearings which while running is very smooth, no vibrations....so I conclude and along with what I see in the old GB Drive train drawing that 2 bearings are correct. My shaft tube was one piece, composite.

Sorry for the long story, but funny that the 3rd bearing scenario would come up again.


Good luck
Mike Dana
Third Reef
36' Grand Banks Classic #819
Potts Harbor, Maine (South Harpswell)

 

[mbdana]

Oh, and I want to agree with Maine Coast's posting...it was a big job...factoring in Boat Yard personnel vacations, seemly GB inexperience or drive train inexperience, our boat was in the shop for 5 weeks. Outcome was fine and the upside was that we were around for deferred maintenance on other things.

 

[mycows]

Hi Shaun, we owned GB 636 25 years ago. She was a 1981 classic. Due to excessive shaft wear we decided on a replacement and we did find 3 bearings. I think this was because of excessive shaft length and possibility of the shaft whipping between bearings. It was a real rodeo to remove the shaft and the bearing came out with it. We used the old shaft and made it into an installation tool and drove in the new bearing. It worked perfectly and we never had any issues after. We reused the old school packing gland with Teflon packing it ran straight and true. The stern tube in our boat was glassed into the hull and buried deep in the keel. Hopefully others will weigh in on whether that center bearing is really necessary….