Mainship Pilot 34, Shaft seals and cutlass bearing change out.

I am in the process of replacing the Tide seals and the cutlass bearings on my 2002 Mainship Pilot 34 twin engine Vessel. The tide seals are original install so 20 years old still not leaking but I was advised by Tide service that the seals should be replaced every 10 years. The original still installed and spares on the shafts. Impressive! The engines only have 890 hours. The cutlass bearings are marginal with .030 play starboard and .060 port deflection. I'm planning a Loop trip so I decided I should just replace every thing and pull the shafts for inspection. I have sent the props out for full scanning, trueing and balancing. I have removed couplings, seals, Props and tried to slide the shaft out. The rudders are slightly offset bit I am lacking about 3/8" to clear the rudders. I still have the rudder tie bar and cylinder attached the rudders. My question have any 34 Pilot owners suggsuccefully pulled shafts without removing rudders. If so how? If not what was the packing size for the rudder stuffing box? I will replace it while the rudders are removed. Thank you in advance for responses.

Since you don't have to remove the shafts to replace the cutlass bearings (but it is no doubt easier) couldn't you remove the cutlass bearings and gain some more shaft deflection to get by the rudder?

David

Boy, it would sure have been poor planning on Mainships part if you do have to pull the rudders out to slide the shaft out. Hopefully you can get some play in the rudders if you undo the tie rod. Good luck!

DavidM said:

Since you don't have to remove the shafts to replace the cutlass bearings (but it is no doubt easier) couldn't you remove the cutlass bearings and gain some more shaft deflection to get by the rudder?

David

Click to expand...

There is a tool that does remove the cutless bearing with the shaft still in. Depends on whether or not your yard has one.

I was going to buy the tool about 500.00 for a 1 1/2" shaft. My plan originally was just replace the Cutlass bearings. After talking to Tides and listening to their advise to replace the seals I decided I would just pull the shafts and then I could press the cutlass bearings out with a mandrel and threaded rod (homemade). At the same time I could inspect the shafts on a V-block, check for straightness, clean the shafts up, install new cutlass with my home made mandrel slide the shafts in new seals "easy peasy" I was hoping someone has done the job and could say free the rudders up and the shaft will just slide by. My gut is the rudders will be coming down. Or spend 500 for tool and then put it on a shelf to collect dust!

Yes, sometimes buying a tool for a one time project is difficult to justify. But if you have the yard do the work you will spend way more than $500 in labor. And I love buying tools…

The high dollar tool thing comes up often enough I keep thinking there needs to be some way of buying them and then selling for a small lose. Maybe some form of a tool section?

DNT99611 said:

The high dollar tool thing comes up often enough I keep thinking there needs to be some way of buying them and then selling for a small lose. Maybe some form of a tool section?

Click to expand...

There is a general for sale section that tools can be listed in on the site.

After removing the rudder tie bar I determined no matter what position the rudder was in I could not get the Prop shaft to clear removed. The rudder was not off set enough. A couple hours later the rudders where dropped and the bearings removed with a mandrel I had. ( Mercruiser bearing installation tool) If you have a 34 pilot with twins and need remove the prop shafts plan on dropping the rudders.

That wasn’t good planning on Mainships part. Too bad.

Cutlass bearings replaced, shafts polished, bearing surfaces inspected and measured within spec, runout measurements within spec, shaft seals replaced, rudder post inspected, new packing, props trued and balanced, bottom painted, thruster gear lube changed, all anodes replaced. Bottom work completed and on to the next project. I'm getting closer to starting the Loop!

Nice work. Not sure if you're interested, but I think you can buy a new-style thruster prop (Q-Prop) that looks like this.

https://www.imtra.com/Portals/0/Images/product/SM71261.JPG

Check here.

https://www.imtra.com/products/sleipner/thrusters/parts-upgrade-kits/upgrade-kits

Anyway, good luck with your loop plans, look like you are on your way.

backinblue said:

Nice work. Not sure if you're interested, but I think you can buy a new-style thruster prop (Q-Prop) that looks like this.

https://www.imtra.com/Portals/0/Images/product/SM71261.JPG

Check here.

https://www.imtra.com/products/sleipner/thrusters/parts-upgrade-kits/upgrade-kits

Anyway, good luck with your loop plans, look like you are on your way.

Click to expand...

Thank you, I thought about replacing the old 4 blade prop when I removed it to clean the shaft and install a new shear pin. The 4 blade was in good shape and I really don't think I will use the thruster that much. I have only operated the boat for 25 hours after I purchased it last fall. We brought it to the marina where I have it on the hard. 200 mile trip 4 locks and two marinas. I never used the thruster. My last boat was a single inboard bow and stern thruster. I did use the thrusters when docking in wind. With this boat being a twin engine I haven't found the need for the thruster. I know I will when the conditions are right or better said when conditions are not right!!!

I need mine most every day due to single prop and fighting river currents. I agree with twins, probably not as big an issue, although it's probably a pretty cheap upgrade. I had to replace my thruster prop because it lost a couple blades when a dock line got sucked in. Around $100 replacement. I think they are made to delf-destruct. The "drive pin" is not really meant to act as a shear pin on mine. The rear thruster does have a real shear pin but it's in the drive mechanism, not at the prop. It can be changed while in the water from inside the boat.

I am hauling out to replace my shaft seals next week.

Where the shaft meets the engine. The shaft coupler I believe.

Is the shaft bolted onto the coupler (similar to the prop at the other end)??

And if it is bolted on to the coupler. Do you know what size that bolt is?

Thank you.

Brian Costello
03 Mainship Pilot 34 w/twin Yanmar

The engine to prop shaft coupler fasteners are 1/2 fine thread bolts with hex head 3/4" and the nuts 11/16". The prop shaft is a double tapered shaft. Meaning it has a taper on the prop end and the coupling end. There is a nut that is used to draw the coupling onto the shaft taper. The socket size to remove this nut is 1 7/16". This socket needs to be a thinner wall socket to fit in-between the nut and the ID of the coupler. I recommend pulling the props first to release them from the taper but leave them on the shaft loosely until you loosen the nut holding the coupler to the shaft. You will need to lock the prop against the hull so the shaft doesn't turn while you are loosening the nut. Once the nut is loosened leave it threaded to the shaft loosely. There is not enough room to use a puller to break the coupler loose from the shaft taper. I used a socket to act as a spacer between the prop shaft and the reverse gear shaft. Slide the couplings together use 3" long 1/2" bolts to draw the couplings together with the small socket in between acting as a spacer. Tighten the 1/2" bolts drawing the couplers together this will release the prop shaft coupler from the taper shaft. Once the coupler pops off the taper. Remove the coupling and the prop and slide the prop shaft back to the rudders. The prop shaft will not clear the rudders but you will have enough room to remove the shaft seals for replacement. In my case I had one cutlass bearing that had some more deflection than I liked so I replaced the both bearings while I had everything apart. This did require shaft removal so I dropped the rudders.

Thank you!! This info is going to save me a ton of time!!

Safe travels on the Loop. If you come to Boston let’s meet up!!

We hope to make our way to New England as we head north on the east coast. Massachusetts is my childhood stumping grounds. My Uncle (Al Gray) owned a boat yard in Taunton MA. He built custom boats and also built the Famous Mackenzie Bass boats in the late 50's and 60's, Those boats were known as the Mackenzie/Gray's. My father did most of the engine installations in them. I was to young to appreciate the working talents of this man then but in the late 80's after he retired, Al worked part time at a boat yard/Marina I worked at in Swansea Ma. He was a master at the trade. I also worked at Slips Capeway Marine in Wareham Ma. for a number of years in the 80's and 90's (marine service technician, Outboard, stern drive and Deisel ) I moved to an area south west of Chicago (90's) and have been in that area ever since. I changed my career occupation from Marine service tech to Millwright and have never been back to the beautiful waters of New England. I boated Mostly on Narragansett Bay, Mount Hope Bay, Sakonnet River, Buzzard's Bay and Taunton River. Spending the summer months with my Portuguese family in New England lead my wife and I to name our last two boats PORT-A-GEE. Hopefully PORT-A-GEE is floating in New England waters in the next few years so I can check another item off the "Bucket List"


Sorry for the story!!! Good luck with your shaft seal project.

Love the story!

There are two Mackenzie’s at my club!

A 1958 and 1967(?). Both beautiful boats.

Port Norfolk Yacht Club, Dorchester MA