Johnson Jw-15 new purchase

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Kenboatman

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Hello all. I just bought a small fishing boat for me and my young boys. It came with what I understand is a 3 hp Johnson jw-15. Fuel tank is spotless, carb looked amazing for such an old motor. So I put in a tub and fired it up. It started way too easy! I didn't see any water spitting out like other outboard motors I have had. So I have an impeller and wear plate kit on the way. I was told it had been sitting out of water for 3-4 years so I figured for the small price of the impeller is worth doing before testing it on the water. I have watched some videos and think it looks like a very diy project. My question is nobody refers to a seal, gasket or oring needed. Is this correct? Or is there something I'm missing. Even in the parts breakdown I don't see a gasket between the lower end and the mid section. Thank you in advance for any insight. Also should this motor push a 11'6" aluminum v bottom boat ok?
 
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racerone

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There is no gasket.--------You MUST install an o-ring in the groove at the top of the driveshaft.------Put grease on the splines of the driveshaft.----------These are an excellent / simple motor.-------Will last another lifetime
 
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F_R

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No gaskets are needed. There is a rubber water tube grommet in the pump housing, and an o-ring around the top end of the drive shaft. Reuse them if in good condition. The o-ring is a very vital part and MUST be in place and in good condition.

Sure it will push the boat if you are not in a big hurry.
 
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Kenboatman

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So if the oring is MIA do I need to worry about digging it out of the motor side? Where might I find the size of the o ring? I need to get a manual ordered up soon for it.

No hurry my boys are 7 & 8 the last boat I had was a flat bottom 14' that I only ran a trolling motor on. This one came with a troll motor two batteries and the 3hp.
 
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hardwater fisherman

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I do not know the size of the o-ring but it is OMC part number 0202893. Or sold here at IBOATS sierra part number 18-7168-9.
 
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F_R

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It is a stock size Buna Nitrile o-ring. But I don't know the size without researching it.
 
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Kenboatman

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Well impeller replaced new wear plate installed water pump housing cleaned all up. Too bad it's 30* outside and snow on the ground. The motor is ready for an in water test. There was some cracking on the old impeller it might have gotten by for a while but now I don't have to worry about it for a bit. The top o ring was in great shape no Knicks or anything. I've also got a trolling motor two batteries and oars so one way or another I can get back to where I need to be if things go wrong.
 
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Crosbyman

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don't forget to check the fuel filter in the tank above the fuel valve.... and.....
clean out the two small holes under the vent cap ..the crud up and even with the cap open the tank will not let air inside the tank !
make certain you can see light in the two holes when the screw cap is loosened
​clean out the silencer of any bugs , webs etc...
 
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Kenboatman

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Crosbyman said:
don't forget to check the fuel filter in the tank above the fuel valve.... and.....
clean out the two small holes under the vent cap ..the crud up and even with the cap open the tank will not let air inside the tank !
make certain you can see light in the two holes when the screw cap is loosened
​clean out the silencer of any bugs , webs etc...
Click to expand...

I was just going to ask about a fuel filter. I did a rinse of the tank even tho the parts I can see are spotless. And the carb looked good. Seems I have a fuel problem of some sort. I backed the boat in the lake and started her up still tied to the trailer. Man this motor starts so easy it's scary. After about 3_4 min of medium rpm the motor starts to bog out. Pulling the choke does little to nothing. So it's either lacking fuel or air. Starts right back up if you wait 5-10 seconds. I did not think to check the vent holes in the cap good tip. I can't believe how quiet and smooth this motor runs. It's been raining since and during the testing so my check of things is delayed for a bit.
 
lindy46

lindy46

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Sounds like a fuel delivery issue. I suspect fuel isn't flowing properly from the tank to the carb, either because the filter is plugged or the cap isn't venting properly. Disconnect the fuel line and allow some fuel to flow into a jar. You should have a pretty good flow rate - if it's a mere trickle you have a delivery problem, and the flow isn't keeping up with the demands of the engine.
 
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Kenboatman

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Cap venting should be easy to test. Just unscrew the main cap and see what happens. I did not know about the filter in the tank. Gas flows well when I open up the lower drain screw on the carb. How many turns does the fuel shutoff normally turn? I get about 3/4 turn it and get resistance..
 
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Crosbyman

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to get and PRINT...off your parts listing for future ref.

google yourself over to the site called m...arineengine.com. follow the menu to reach your 59 jw15

to access the site remove my extra dots in my link URL

I added them in just to circumvent the editor on this site which removes parts competitive sites
 
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Kenboatman

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I'll work the valve some. Thanks for the info Crosby man I have already found parts fishe' sites and scoped things out. Hopefully the weather will l turn around this week and get more spring like.
 
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Kenboatman

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Thought I would pop back in and report. I checked the cap holes all clear. Since it was in the 60's not 30 out I took the boat out. She ran great with no problems both yesterday and today. First day was a few miles up the river, today about three hours on the lake. Start and stop many times used the trolling motor, it started without fail and ran great. I'm amazed at how something made so long ago can run so well.
 
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