Converting 5411 to Electric Drive - removing old coupler

[rob452]

We have finally accepted that our aging 5411 (1980) is no longer up to the task at hand and have committed to replacing with a 10KW electric drive from Thunderstruck.
We now have the old diesel out but are having trouble figuring out how to remove this rusty old coupling so I can get at the bare shaft.

If anyone can point me in the right direction, I would be eternally Grateful.

Thanks,

Rob
Kelowna BC Canada
SV-Althea
1980 Catalina 30 - Hull# 1712

 

[Michael Davis]

After using a good gear puller and a lot of heat I finally decided I needed a new shaft and resorted to a hacksaw. New shaft came with a new prop so I was happy in the end.

 

[rob452]

Yeah, that is my plan C - hoping someone saves me from getting there..

 

[Michael Davis]

By the way ,the 5411 is a very easy engine to rebuild and would be a lot cheaper than what you are planning.

 

[jssailem]

Like Michael, I had to decide about the shaft after I got the engine out of my boat.. It was a slam dunk decision. I opened the stuffing box and slid the nut a bit towards the coupling. This let me look at the shaft. It was toasted.


Then I let my sailing buddy, who just loves to cut things apart on my boat, have a go at grinding through the 1.38” shaft.


If you find there is not enough room to do the cut, I suggest you push the shaft a little up and into the boat.

 

[jssailem]

Interesting project. From your location I suspect you are lake sailing. The use of your engine is minimal, getting in and out of the marina. Long powered runs up or down the lake are not expected. If you find your self windless on the lake is your plan to sit quietly at anchor should the battery pack be depleted and awaiting the sun to peak out and begin the process of recharging.

I ask this as I could not find on the Thunderstruck site a power consumption chart to provide the need for battery sizing based on boat displacement. I guess that would be calculations they might provide when you give them your boat and battery information.

I did take note of this bit of info…

In the U.S. and Canada, brushed motors are only legal for marine use if onboard appliances and accessories use kerosene or diesel (not propane or gasoline) due to the potential for internal motor arcing.​

It appears even after investing in EV Boat conversion it is difficult to abandon fossil fuels.

 

[Tally Ho]

My shaft and coupler look a bit different, but here is how I did mine. But in the end, I replaced the 30+ year old shaft.

Greg