Stern Thruster - Is this a freaking joke?

[kelpline]

Our stern thruster picked up a rope last summer, which broke the shear pin. Since I am crazy about mucking around on boats, and my wife wants to learn how to dock our Cutwater 28, I decided to tackle changing the shear pin. Purchased 2 shear pins from Port Boat House, Port Alberni, and read all the Tugnut postings about stern thrusters. Bought 2 small racketing wrenches from Amazon: https://www.amazon.ca/gp/product/B000XY ... UTF8&psc=1 AND CRAFTSMAN Screwdriver Set, Ratcheting, Multi-bit 10-Piece (CMHT68008). I shortened a 6mm Allen wrench with a cut-off blade, so the bottom of the L is 3/4" and the long arm 31/4",saving the cut off bits to use as 5/8" hex bits in the 4" Neiko racketing wrench. On a Cutwater 28 (2011) the outside stern seat comes off fairly easily; below the hinge lid, fiberglass tub has a few screws, easy, to expose the stern thruster motor down to port. The rudder arm was disconnected from its hydraulic ram, pushed aside. Note picture of correct position of me working on it. My wife said later she probably could have fit down there, but was enjoying seeing me suffer. I cut two 8" 2"x2" dressed wood and joined them via strapping to create a cradle under the motor. And cut the heads off two 8mm x 50mm bolts, with a flat screw driver slot in their ends to serve as guide bolts for remounting the motor (this was the best hint I got from Tugnuts Folks, it really made remounting easy). A hold down strap was tide forward and behind the motor flange to lift it onto the top of the poop tank, where the old pin easily vacuumed out, new pin installed pointing to 12 o'clock, the same angle as propeller gear yoke. The motor went on smoothly with the temporary guide bolts, a nut on the central stud secured the motor while I used the 4" Mastercraft racketing wrench with a slot bit shortened to 3/4" to back out the port stud. Replaced with proper hex head 8mm x 30mm bolt, well greased. Replaced central stud with prop bolt, well greased. Took next day off the repair chest and lungs.

 

[rpmerrill]

Proud of you kelpline!

The alignment studs were my idea. If you had to do it again it would take half the time.
Wait until you get to do the bow thruster. The studs were even more helpful there.
It's in such a remote place that Stevie Wonder could do it as good as anyone else.

Posting a photo.... now that's a different story. I think I have read the instructions several times but only posted a photo once. I assume you have installed the photo in your album?
Then you click on one of the message header items. Might be "g2Img" and then somehow it directs you to select an item from your gallery.

I just found this:
************************************
There are two ways to embed images in your posts.

If the picture you want to include is in one of your gallery folders (on Tugnuts), click on the g2Imgbutton. That will open another window which will allow you to browse your galleries and select a picture. Be patient, it can take a while for the new window to populate. It should default to your album when it opens.

Click the box in the upper left of the picture you want to post. Scroll (way) down to the bottom of the window and click Submit. That will attach the picture to your post.

If the picture isn't in your gallery, perhaps something you've seen elsewhere on the web, or in another personal web collection (i.e. flickr, iCloud, google, etc.) then you click the Img button. The image/collection must be open to the public.

This will create the following string in your posting window - then you copy and paste the URL (http://whatever...jpg) of the desired image in the middle, between the ][ brackets. The trick here is to determine the direct URL of the image. Various image hosting sites show it in different ways. Sometimes it's right up in the address bar. Other times it's listed under "Share This Image", etc.

You can determine if you have the correct URL by hitting the Preview button. If it displays, you're good to go. If it's not correct, the form will give you some kind of clue so you can go back and dig around. You'll only have to figure it out once for each host.

 

[Bruce Moore]

I will post some pictures if I can remember how. Could someone please remind me how to add pictures?

There are two ways to embed images in your posts.

If the picture you want to include is in one of your gallery folders (on Tugnuts), click on the g2Imgbutton. That will open another window which will allow you to browse your galleries and select a picture. Be patient, it can take a while for the new window to populate. It should default to your album when it opens.

Click the box in the upper left of the picture you want to post. Scroll (way) down to the bottom of the window and click Submit. That will attach the picture to your post.

If the picture isn't in your gallery, perhaps something you've seen elsewhere on the web, or in another personal web collection (i.e. flickr, iCloud, google, etc.) then you click the Img button. The image/collection must be open to the public.

This will create the following string in your posting window - then you copy and paste the URL (http://whatever...jpg) of the desired image in the middle, between the ][ brackets. The trick here is to determine the direct URL of the image. Various image hosting sites show it in different ways. Sometimes it's right up in the address bar. Other times it's listed under "Share This Image", etc.

You can determine if you have the correct URL by hitting the Preview button. If it displays, you're good to go. If it's not correct, the form will give you some kind of clue so you can go back and dig around. You'll only have to figure it out once for each host.


Cheers,


Bruce

 

[BB marine]

And cut the heads off two 8mm x 50mm

Nice write up. I'm assuming 8MM 1.25 coarse threads? or 1.0 fine? The 50MM length is that what you used ? Would plus or minus that length help or is 50MM the go to? I like the idea of cutting slots for a flat blade. I'm making up a set of these now just wanted to see if any fine tuning to the length would help or hurt for removal.

 

[rpmerrill]

As I recall they were 1.25mm threads. At least I'd have to say they were coarse threads because the fit into the tapped holes was easily finger loose. I wouldn't have predicted that screwdriver slots would have been needed.

Were they needed, kelpline?

Thinking of the crazy location where this work is done.... finding the screw slots could be a project in itself.
Ha.

 

[kelpline]

Hi Brian, The thread looked to be fine 1.25, and of course matched the original bolts' threads. The length of the stud was dictated by the limited supply we have locally; the longer length bolts did not have full length threads, and I don't have a set of metric taps. Another 5mm of length would be handy, but soon a longer stud runs into the curve of the motor housing.

Were they needed? One side came out easily, the more difficult port side needed the slot, maybe I tightened it too much.

Howard

 

[CAPTCRUNCH]

A modification that proved useful for my stern thruster service team (my son and me) has been to replace 2 of the many bolts that fasten the plastic vapor shield onto the flange with eye bolts so that we can use a cobbled-together lifting rig (basically 2 tethers) to lift/lower/rotate/nudge the motor assembly.

 

[rpmerrill]

I just remembered my tools are in the trunk of the car for the winter.
My two studs are there.
Mine are about an inch and a half long.
Threads are 1.25 mm

 

[BB marine]

I just remembered my tools are in the trunk of the car for the winter.
My two studs are there.
Mine are about an inch and a half long.
Threads are 1.25 mm

The thread looked to be fine 1.25, and of course matched the original bolts' threads.

Thanks guys! rpmerrill the shorter 40mm length was adequate ? I think the shortest length would be better for removal. It has to be long enough to work. I have not (knock on wood) had a shear pin failure yet but I want to be prepared. I'm going to put the slots in just in case. Hopefully the alignment pins walk out with fingers.

 

[rpmerrill]

I think when carrying the weight of the thruster, the pins might bind up a little. As I recall it might be one of those things where you take the weight off, by hand or the hoisting straps, and the studs are loose.

I can't wait until I have to do that job again.... NOT!

Seriously, I would do another thruster before I ever attempted a water pump impeller again.