1987 Prostar 190 project boat

[mckyle]

well, I spoke to someone at Skidim who suggested that it was risky to try and wedge something between the two halves, because I don't want to gouge the face of the transmission side. They suggested putting a prop puller on the end of the shaft and giving it a few good whacks. I picked one up off cragislist tonight for $40 so I'll be trying that tomorrow. I did try tapping and rotating a bit like you suggested, but was unsure if that would damage anything(?), so I didn't try for too long.

[gweaver]

Given the condition the transmission end is in, I'd probably pull that side off as well and take it to a machine shop and ask them to clean it up a bit. At a minimum, put it in a vice and take a wire wheel to it to get most of the rust off. Maybe they could put it in a lathe and take a couple of thousandths off to get it back to clean.
G

[d2jp]

Have you tried PB Blaster or Kroil and keep soaking it with that for a few days? I haven't seen anything that stuff can't break loose with enough soaking and some tapping and/or CAREFUL application of heat.

[rjracin240]

Originally Posted by d2jp

Have you tried PB Blaster or Kroil and keep soaking it with that for a few days? I haven't seen anything that stuff can't break loose with enough soaking and some tapping and/or CAREFUL application of heat.

Went through the same with my boat, even used Kroil and PB Blaster.......a little heat from a propane torch worked wonders!

Definitely would stay away from the chisels and such at this point.

[mckyle]

well, good news and maybe bad. I was able to get the coupler apart from the transmission flange. I kept banging on it with a rubber mallet, turn, bang, turn... and I could see it start to separate, but because of a lip on the face of the coupler that fit inside the flange I couldn't loosen it completely that way. I then attached the prop puller and gave it a few good whacks and it separated.

Now, thinking I could get any 4" coupler to fit a 1" single-tapered shaft and my Borg Warner, skidim says theirs won't work to replace? This is the one they said would fit my Borg Warner Velvet Drive http://www.skidim.com/prodinfo.asp?number=CPST4X1.0 - but said it would not replace the coupler I have. I am very confused. I know they aren't the same...but I was thinking it would still be fine. I attached a picture of the one currently on there. You can see the nut inside the coupler, and has a cotter pin (some pics show it removed) through the end of the shaft to hold the nut. I've looked on a lot of websites, and they all sell the same style coupler as skidim. Could anyone confirm which coupler I should use?

Also, to remove the transmission flange, do I just remove the nut inside the flange? I want to clean it up as suggested.Thanks!

[mikeg205]

You might want to also get to midwest mastercraft and bay area watersports for hard to find parts. +1 on adding heat to coupler and using puller...nothin' like a rust weld to take on...

[mikeg205]

Might be a good test case for evaporust... http://www.evaporust.com/

might try finding a rusty riser and see what it does to the inside....I am sure I can get an old rusty one for a good price..

[mckyle]

So evidently I have a double tapered shaft, not single. Thank you skidim for pointing this out. I found what looks like an exact replacement: http://www.nautiqueparts.com/coupler...rectdrive.aspx but I'm waiting on a call back to confirm the bolt pattern will fit.

[gweaver]

I don't know what your budget is, but for the price of the coupler above, I'd think seriously about replacing both halves of the coupler. Get rid of all that rust and sleep well knowing you've got good, clean metal down there.
G

[mckyle]

@gweaver Well, I am going to take my chances cleaning it up. I did consider it, but if I can't get it cleaned up to my liking I may go that route. Any idea how to remove it? Just looking at it, it seems all I would have to do is remove the large nut shown in the picture. I'll be trying that hopefully soon unless someone suggests otherwise. Thanks!

BTW, I did confirm the link to the coupler above is the correct one. I've got that on order, plus new Vesconite strut bushings, and packing rope. Figured I'd replace all of those while at it.