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1963 40hp Johnson RKL-25D

OMC gear cases and parts of this era are " precision stuff " and no backlash checks are needed on the wonderful electramatic shift units. --Assemble the parts with care , pressure test the lower unit to make sure it is sealed.-Fill with the correct oil and go boating.
 
Thanks guys. I got the unit back together and fashioned an attachment for a bike pump to check pressure. I pumped to ~10PSI and unfortunately pressure slowly drops. Spraying seal at top of water pump shows no bubbles, but I do get bubbles at the prop shaft seal (darn!). Before I pull off gearcase head, pop the seal that is leaking (the one I just installed!) and retry with another new seal, I thought I would check on whether there are any suggestions beyond what I just described?

Also, is it likely I would need to replace the little seals that go around the screws that hold the gearcase head or should I be able to resuse the ones I just installed new on my last attempt? I ask because if retrying with a new seal is the course of action I will need to order another seal for the prop shaft and wondering what else I will probably need.

A related question has to do with the prop shaft...it seems that there is a small groove 'worn' into the shaft at ~ where the seal sits. I have this groove on both my shafts (from both the original and from the parts motor) and assume it is from wear, but don't know for sure. Could this be part of the problem with getting a good seal? Thanks for your help - I am determined to get this thing working!
 
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I would not re-use the o-rings for the screws.----I get them from an aftermarket place $0.30 each.----------A new seal should be able to handle slight wear on the shaft, but you can try to reposition the seal in the housing to get on a good surface.
 
Thanks for the guidance. I will see if I can tap the propeller shaft seal in a bit further and get a good seal (boy those new drive shaft seals cost more than I would have thought, will around a bit for better price if I have to replace..almost as much as the whole kit!), maybe I will get lucky and not have to pull the gearcase head out!
 
Well my new seal for prop shaft arrived and I pulled old one and replaced and left new seal out a hair as suggested by kimcrwbr1 and racerone. That seems to have done the trick. Thanks for the advice - it did the trick once again.

As I prepare for reattaching my LU to my exhaust housing I had couple more questions. The first is that it seems there is a gasket underneath the exhaust housing plate...the gasket is part 308344. My motor was missing this part so I would need to order one (appears they are available). My question is whether I can use a gasket making compound instead (and avoid the wait of another part!). Also, should I put a grease on the upper splines of the drive shaft - if so any particular kind? Thanks for the continued support - it has been priceless!
 
The gasket is nothing special , make it with some thick material ( nothing special at all )--------grease on the spline and a new o-ring on the driveshaft groove.
 
Well I managed to get the lower end bolted back on and checked the endplay on the drive shaft - that part went fine. I rewired motor to the controls/junction box/battery etc and have it all on a stand in workshop (I had removed motor and controls from boat as i did a complete restore/paint of the boat).

Unfortunately when I turn ignition, nothing happens!. Starter is fine (it responds to direct jump to the batt). Voltage on ignition circuit when taken at the selonoid is 12.6V when ignition turned to start (of course 0V otherwise). Voltage across selonoid (battery and starter side) is at 12.6V when ignition off and remains there when ignition turned on, so clearly selonoid isn't closing and passing current on the starter circuit. I can hear it click when ignition turned, but juice isn't passing through to the starter, so I guess it isn't closing properly. Any suggestions? Is there any reason beyond a bad selonoid for the above issues?

Also, I am not sure how the cut-out switch/safety switch plays into this picture - it is connected to the other side of the selonoid - could a problem there cause symtpoms above?

Any help would be appreciated. Thanks again.
 
Thank you kimcrwbr1 for the guidance. This is what I found:
1) I have 12.5 volts between the battery cable and the ignition side of the selonoid coil. I also have 12.5V on the safety switch side.
2) If I do the same test while turning the ignition to start, I have 0V on ignition side (so it appears ignition circuit is working). I get 6V on the safety switch side when ignition is turned to start - not sure what that indicates?
3) If I ground the safety switch side of the selonoid circuit to the motor housing and turn the ignition, the starter will fire.

It seems that starter firing when safety switch side of selonoid is grounded to motor means 1) selonoid is fine, 2) that issue is in the safety switch circuit (I guess this means switch is 'open' when ignition is turned to start?).

What is a bit confusing to me is that in the test you suggested I was getting a 12.5V drop between the battery cable and the safety switch side of the coil - wouldn't this mean that the safety switch side of the circuit was indeed grounded (switch 'closed')? Also, what does the 6V drop when ignition turned indicate?

In any case, your next step suggestions based on the above information would be great! I will investigate the safety switch side of the circuit a bit and look forward to your input. Thanks again.
 
Thank you kimcrwbr1 for the guidance. This is what I found:
1) I have 12.5 volts between the battery cable and the ignition side of the selonoid coil. I also have 12.5V on the safety switch side.
2) If I do the same test while turning the ignition to start, I have 0V on ignition side (so it appears ignition circuit is working). I get 6V on the safety switch side when ignition is turned to start - not sure what that indicates?
3) If I ground the safety switch side of the selonoid circuit to the motor housing and turn the ignition, the starter will fire.

It seems that starter firing when safety switch side of selonoid is grounded to motor means 1) selonoid is fine, 2) that issue is in the safety switch circuit (I guess this means switch is 'open' when ignition is turned to start?).

What is a bit confusing to me is that in the test you suggested I was getting a 12.5V drop between the battery cable and the safety switch side of the coil - wouldn't this mean that the safety switch side of the circuit was indeed grounded (switch 'closed')? Also, what does the 6V drop when ignition turned indicate?

In any case, your next step suggestions based on the above information would be great! I will investigate the safety switch side of the circuit a bit and look forward to your input. Thanks again.
 
Checked the safety switch this evening and it was fine.

I carefully checked the wires from the junction box to the motor and it appears the issue is in there. All of the wires read about 6ohms of resistance on the meter with one reading over 300ohms (one of the shift wires) and 1 not reading anything (the overheat wire). As a final test, I ran a new, temporary wire from connector in junction box to motor for the selonoid circuit and starter kicks when ignition turned to start - so it appears wire from junction box to motor is bad somewhere in that big long bundle (maybe they are brittle and broke when I removed motor/cables from boat).

Also, I checked resistance on same wires on the 'parts' motor and all wires are below 1ohm (but unfortunately the connector is bad, so that needs some work), so I am guessing 6ohms is probably an issue. Looks like I will be swapping the cables/rewiring. Any suggestions on products available for putting a new sheath around the new wires so it is in one neat bundle like the original?
 
Thanks. I put new connectors onto my 'parts' motor cable and wired it into the motor. I will look for shrink tube that will fit over my connectors and put that on when I disconnect from j-box for installation into the boat (tough getting all that stuffed into junction box!).

Good new is the old girl fired up and ran. I idled her for 15 mins or so and then checked forward and reverse and blew out most of the water in the barrel, so seems gear shifting is working fine now.

Question: Water pump seems to be doing its thing - hot water comes out the exhaust port at low speed, but stops dumping water in the top exhaust at high speed - if I recall this is normal as water would be dumping out exhaust port under the cavitation plate at high speed - correct?

The 'start' lever needs adjusting as does idle I guess as motor stalls out when I push the start lever back up to the top position (vs down position for start). Seems to run fine with start lever in 'half-way' position though.

Question: where should the lean/rich knob be if engine is running normal - in the halfway position?

Thanks for your guys' continued help for the past couple of months - I think it is another success story thanks to your advice!
 
My motor seems to have only 1 knob, low speed, on the front of carb. What would the adjustment process be for this set-up?

I do have a temp light and I know wiring is good, will check the light though as suggested by grounding - good idea. Oddly the temp light is on a panel with electric choke switch, but my motor doesn't have electric choke, it is vacuum/mechanical (electric choke wasn't added until 1964 I think), so guessing setup isnt original.

Anxious to get on the water, but won't have a chance to get her wet until late part of July. Motor will be remounted on a 1965ish Starcraft Jet (15ft runabout). Few minor things left on the boat refurb (biggest task is to polish scratches outa the windshield) and she needs to be re-registered (luckily I have original registration and title from PO), fun awaits at the DMV.

Few things to sort on the motor yet:
1) rubber gasket/trim between motor cover and motor housing is shot - need to find suitable replacement (any ideas welcome!)
2) ammeter seems to be broken and I want to check generator to ensure it is functioning (I think it is as my voltage reading off the junction box terminals went above battery voltage when I was doing the barrel test).
3) was considering whether to paint motor now that it is off boat - it looks pretty rough compared to new boat paint, but can only do rattle cans on motor vs spray gun, so not sure if feasible/effective with moeller or rustoleum and if worth the effort as rattle can paint doesn't seem that durable.

Thanks for the guidance on oil mixture - I had tested with 50:1 ratio, but seems some guys run richer on these older engines. Glad to hear 50:1 is enough as it already smokes pretty good - definitely not clean burning compared to later models.
 
The choke on a 63 model ( if original ) is controlled via water circulating thru it.---------Make sure the thermostat is operating correctly.----Later models used hot air drawn into the carburetor over a bimetallic element.
 
quick thanks to racerone and kimcrwbr1 - finally got a chance to hit the water with my son and launch the old refurbed starcraft today (been waiting for about a month to get the time) and the 1963 Johnson seemed to do pretty good on the water. Starts up, idles and runs WOT.

Only issue seems to be on the charging system and was wondering if you guys had any suggestions on troubleshooting this area - beyond running with a spare charged battery in the boat and only going out after charging on land! :).

This is what the symptons are:
1) according to service manual, if charging system working, then I should get greater than battery voltage at the acc terms on the junction box when running at 3/4+ throttle - I am seem to be getting only getting battery voltage, so I think I failed that test.

2) my ammeter shows o amps while running in forward at up to about 3/4 throttle, then meter seems to show negative amps when running 3/4+ throttle and above. I didn't check this reading with my multimeter, was just going by what the dash gauge showed (I replaced old OEM meter that didn't seem to work with new 20amp meter from tractor. Frankly I expected gauge to show negative anytime magnets were electrified (motor in gear), if charging system was not working, instead it just shows negative at 3/4 throttle plus???? Given manual says charging systems turns on at about 3/4 throttle, I started to wonder if I hooked the gauge up backwards and need to swap pos and neg? I didn't try this switch this though as I thought I should run it by the experts.

3) most troubling, I was getting a 'clicking' sound coming from the junction box at 3/4 throttle and above - sound was loud enoug to hear over engine noise from driver's seat.

4) to play it 'safe', I pulled out the charging system fuse from the box to disconnect regulator and this stopped the clicking noise. so I assume noise is coming from the regulator.

*****Any suggestions on how to proceed? Does this clicking sound mean my regulator in the box is shot, but generator on engine my be working?

Again, thanks for getting me running on the water. We (my 13 yr old and I) had a great time and ran the boat for about 45 minutes today and will be going back out tomorrow. Any idea of how long I should be able to 'run' the electric shift system from battery without charging system working (I will be taking a spare fully charged battery and keeping fairly close to home).
 

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Thanks for the quick response kimcrwbr1. I am a little confused on the testing of voltage regulator...'Next test the voltage regulator with everything connected after you polarized it Run the engine around 2000 rpm and hook a jumper between the field wire on the generator and a good ground you should read charge on the amp guage.'

shouldn't amp gauge (the one in the dash, not on multimeter), show it as charging without running jumper? clearly I am not following, can you try explaining that part again?
 
gents, another more pressing issue arose today on the lake, unrelated to the generating system issue (which I didnt yet get sorted out). I am having problems with the carburetor - engine is spitting fuel out the small port near the slow idle adjustment knob and the front when trying to start the engine. Not sure if related to this problem, but I started having issue when I swapped out my original oldstyle omc tank for a new moeller replacement. The first issue was the line from the tank to the engine didn't seem to vent properly with the new tank as the pressure bulb on the line would get sucked in flat once the engine turned over and then engine would stall out (bowl with fuel filter would go dry). I tried unhooking and rehooking this new tank, but same issue (the line definitely was holding a vacuum). When I then tried to go back to the old tank, this is when the 'fuel spitting' issue began? Any suggestions on where to start? I am wondering if I need to tear down the carb and rebuild or perhaps problem is in the fuel pump? That said, it seems strange that engine was working fine before trying this tank switch, so thought I would check with the experts before proceeding. Any suggestions in diagnosing the problem would be appreciated. as I am new to engine repair, go easy on me!
Thanks.
 
kimcrwbr1 - thanks for the quick reply. On the primer bulb question...it pumps gas out the carb, doesn't get hard!

I will try tapping fix (i gave it a tap this afternoon, but didn't rap to hard), but will also order up the carb kit 439074 just in case - it appears the kit comes with needles and float. unfortunately my spare motor is about 140 miles away from where I have my boat in the water, so won't be able to access the spare until I am back home in a week or so, but will see what I can do with the main engine.

great article on the regulator! how did you find this! by the way, are regulators/parts still available if mine is toast (although I won't be working on that problem until carb issue sorted). At least my lower unit rebuild isn't causing me any issues.

any thoughts on whether I should have any issues running this old motor on a new moeller tank with the new OMC fittings on the tank? still not sure why my pressure bulb was going flat as if line/tank wasn't venting?
 
Thanks - the second set of raps with the wrench failed to free the float, so I guess I will be disassembling/cleaning carb. Still waiting for carb kit to arrive, but will attempt to remove/disassemble carb while waiting.

In reading through my service manual for this motor, it looks like I need to remove starter and generator in order to take carb off - does this sound correct? Also, as I have never taken a carb off/rebuilt, a bit intimidated, but will give it a go. After getting carb off, my service manual for this motor says to remove fixed high speed jet and to prevent damage to threads in the float chamber assembly, use "fixed jet screw driver" (special tool #379664). Does this jet need to be removed/cleaned? What does this special tool look like and is there a substitute?

Also, based on picture in manual, it appears this 'screw' for high speed jet is accessed through drain hole at bottom of carb, after removing drain plug? - is this correct? Frankly it doesn't seem right as the 'carb assembly view' only shows the screw plug, washer and orifice plug being at bottom of carb, but the figure labeled 'removing fixed jet' in the manual shows a tool being inserted into hole where drain plug would come out of??? Does my question make sense?
 
There is nothing to be scared of in cleaning one of these simple carburetors.------The high speed jet ( orifice ) will usually come out with a 3/16" diameter shank screw driver.-----Your manual is CORRECT--There is a drain plug and the orifice and nothing else !!
 
racerone - thanks for the encouragement, guess if I was able to get lower unit/gearcase sorted (with the assistance of yourself and kimcrwbr1) i should be able to handle the carb! in order to clean one of these carbs, it does need to come off, correct? Does the carb kit with float have everything (parts wise) that is typically needed? any recomendations on cleaning solvent to use? sorry for the simple questions.
 
After running would you need to pull the starter and generator off again in order to tighten the nuts on the carburetor.----Seems like a silly way to do this job.
 
kimcrwbr1 - sorry but I don't know how to check/adjust the sync - can someone elaborate?

Racerone - any other suggestions beyond what has been posted so far?
 
Got the carb kit the other day and took the carb off. the last set of instructions on sync were clear, so I understand the sync process when I get there - thanks. Should have it back together tomorrow.

question, based on my symptons, is there any reason to take the automatic choke off the carb (as described in service manual), or can I leave it alone.
 
thanks for the quick reply - let me try my question again as I wasn't clear.

the auto choke seemed to be working fine before my carb became fouled - likely sticky float problem (gas would get pumped out the front of carb when prime bulb squeezed).

The carb service instructions in the Johnson service manual show removing the auto choke for cleaning and service while doing the carb cleaning. Given I wasn't having problem with auto choke, I wasn't planning on touching the autochoke (if it aint broke don't fix it theory), just leaving it alone. Sound ok?
 
Thanks - what do you think about the condition of the two low speed needles in the picture below? The one on the right is from the working motor, the one one the left is the parts motor. Which one appears to be in better condition (if picture large enough to tell)?

IMG_1820[1].JPG


what is odd is that the taper at the tip appears to be different on each, not just from wear, but as if the part was slightly different? I looked on ebay and the two shown there appear to be different (one with a more slender tip like my parts motor, the other with less taper like my runner part)? Thoughts as to which one I should install in my running motor?


below is picture of needles for sale carrying 308076 part # - these two tips appear different from each other as well - any thoughts?

$(KGrHqVHJ!0E+Owq0!j9BP3373Bdww~~60_12.JPG
$(KGrHqN,!g0E-8sG8DnfBP6bk)4k-Q~~60_12.JPG
 
Thanks - I went with the pointy one as port was plenty deep. Will barrel test tomorrow once I bolt it back on.

my parts schematic shows lock washer then nut for attaching carb, but both my motors only have nut, no washer. i think the washer is a star washer - guess I should try and round a couple up somewhere, huh?
 
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