382918 Gearcase water tube configuration questions.

[1946Zephyr]

Hello all, I just recently purchased a new gearcase housing for my '59 Johnson RDSL-21b and it has a different watertube configuration than what my original had. After looking at the configuration on a 1970 model, it looks to be a close match.

Below, are two watertube holes in the gearcase. From what I can understand from the 1970 configuration, the rearmost hole connects a water tube to the upper midsection. and the front hole (towards the shiftrod) goes up to the waterpump housing.

Below is the waterpump housing I got with the gearcase and the small tube that goes to the front hole in the gearcase.

Below is the picture with the waterpump housing mounted in the gearcase. The port side of the waterpump housing does not appear to have any through hole passages, as though it's a dummy, but the starboard side does have a through hole passage which I believe goes to the other upper midsection hole.

Has anyone worked on this type of lower unit before? Anyone who can give me some clarity on this matter, would be very much appreciated.

 

[1946Zephyr]

Re: 382918 Gearcase water tube configuration questions.

Wow, 63 views and no answers yet? Where are all the smart guys at?

 

[boobie]

Re: 382918 Gearcase water tube configuration questions.

Does the p/h require 1 or 2 water tubes from the water pump ??

 

[1946Zephyr]

Re: 382918 Gearcase water tube configuration questions.

Does the p/h require 1 or 2 water tubes from the water pump ??

From what I can see, the port side (top hole of p/h on bottom photo) does not even have any waterflow holes from the pump itself. It does however have grommet holes. The starboard side (bottom hole) does have waterflow passage from the pump though. From what it looks like, they re-routed the return tube to the rearmost hole down in the lower unit cavity instead of the top of the p/h.

 

[1946Zephyr]

Re: 382918 Gearcase water tube configuration questions.

Well, it looks like I pretty much have things figured out. Thanks for your help everyone.

 

[nwcove]

Re: 382918 Gearcase water tube configuration questions.

what was the conclusion???

 

[boobie]

Re: 382918 Gearcase water tube configuration questions.

X 2 on the above.

 

[1946Zephyr]

Re: 382918 Gearcase water tube configuration questions.

Well, it appears that the starboard side connection, on top of the waterpump housing (item 1)is the one that pumps the water up to the powerhead. Now I just need to look at my old set up and see which tube connction in the upper midsection, is the one that is the inlet.
Then the outlet pipe (item 2)goes to the rear most hole in the gearcase. The frontmost hole in the gearcase has the short tube (item 61)going to the downward connector on the waterpump housing. The top portside connector on the waterpump housing is a dummy, because now the return line is angled downward, toward where the front hole is in the bottom of the gearcase. It looks as though I need to pruchase Item 2 On the diagram below though, it looks like the outlet tube connection on the waterpump housing is opposite of mine. That could be a goof up on their part. On my waterpump housing, the the tube that feeds water to the powerhead is on the starboard side, rather than the port side. The factory made all these radical changes, so they could do away with the pick up screen on the side of the lower unit and divert all the water pick up to the one on the rear. Where the little plug is, that holds the screen in the pick up point, they have a hole in it, so you can pick up water in reverse.

It should be quite interesting to get all these water tubes stabbed correctly. It'll probably be easier to do, with the powerhead removed. Since I'm going to strip and repaint this entire motor anyway, that's what I'll do.

 

[yorab]

Re: 382918 Gearcase water tube configuration questions.

I had a very similar problem with my '63 75 hp. I tried in vain to figure out the pipe routing but I couldn't. I went with the official parts diagram and it was wrong! I had to then cut the longer pipe with a pipe cutter and add a section to the shorter pipe using a push-on union. I have a some posts on that.

Anyway, ebay is always a good place to look at pics in order to determine hose/pipe routing, wire routing, etc.

 

[1946Zephyr]

Re: 382918 Gearcase water tube configuration questions.

Well, I got it all together last night and this is what it's looking like. All I need to do, is purchase a return line. I may just go to Gormley Plumping and pick up a piece of copper tubing and make my own. They only want $20 at marineengine.com, but a piece that long should be less than half and I don't have to pay shippin'