1953 25hp Evinrude Big Twin

JoeFromAkron

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I finally got my 56 15 hp running good, so i upgraded. I found a 53 25hp that came off someone old wood boat. Its in reasonable shape. Not to many scratches, all there and the gearcase had good oil in it. I also got the controll box/cables/connectors that are in perfect shape. Not one scratch even on on em. Also got one of the older style rectangle shaped fuel tanks. All for $100 so I think i did good. I just had a few questions before i get it tuned up.
1. The points are the same for all the 50's evinrudes up to 40 hp right? I should be able to use the same kit from the 56 15hp?
2. There is no "window" to disconnect the shift rod to drop the lower unit. I went to the boatinfo website for the johnson service manual and i cant figure out exactly what to do to disconnect it. There is something about unbolting it and it will drop 1/2 an inch to get to the coupler but i dont know if thats for my model. Does anyone have an idea?
3. The choke knob is missing. This thing is manual start only and i know the suck a lot of gas. I was reading on here and other places that you can actually flood these using the choke? I took the cover off and trued to start it using the choke and it sucked so much gas it was slightly dripping out of the carb.

4. I dont think im getting a spark. Its kinda hard to tell because its pretty hard to pull over compared to my 15hp. Is there anything thats drastically different compared to my 15hp to change the points ect.?

Thanks
 

racerone

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It is the exact same magneto , so easy to inspect and fix.---There may be a wee plate where the lower unit bolts on that hides a shift coupler.---Used to run one of those motors on an 11 foot class " b ' racer.---Lots of fun and a rugged motor.---Will outlast the new plastic junk and does not have $500 modules on it.----So it uses a bit more fuel, but that may not be an issue if you have $200 invested instead of $5000.
 

Chinewalker

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1 - Yes, the points, coils and condensers are the same as your 15.
2 - There is a coupling. I believe you have to remove the 6 bolts that hold the lower unit to the exhaust housing in order for the lower unit to drop down a bit. Then the coupling will be visible. DO NOT remove the coupling bolt with the lower unit hanging from the shift rod, as you will wipe the threads off the bolt.
3 - I'm not certain, but I believe part number 302760 will work for you as the correct choke knob. There are a couple on eBay, etc.
4 - Nope, the ignition is pretty much the same and sets up the same way.
 

HighTrim

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When you test spark, take the spark plugs out. Makes it easier to pull over. Ground the lead not being tested.
 

JoeFromAkron

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DO NOT remove the coupling bolt with the lower unit hanging from the shift rod, as you will wipe the threads off the bolt.
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4 - Nope, the ignition is pretty much the same and sets up the same way.

You mean to suppoet the gearcase while unscrewing the bolt? Thats good to know to make sure to do. I probbally would have just had at it
 

HighTrim

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Yeah leave a couple bolts in a few threads, remove the bolt from the bottom of the coupler, shift into forward, pulling the shift rod out of the coupler, then drop the lower unit.
 

oldboat1

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motor and controls in good shape, boat too or was that long gone? need a period boat for that beauty.
 

JoeFromAkron

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Thats what i was thinking leaving the bolts just barely attached.
I looked under the flywheel this afternoon and its got what looks like brand new coils and points so i dont know why it wont spark. The points are gapped right and clean.Time to pull the flywheel. The plug wires look pretty old.
The guy i got it from actually lives on a chain of lakes here in NE Ohio and bought an old wood boat of some kind and the motor was on it. He seemed pretty wealthy and planned on restoring the boat but was moving and decided the boat was to much hassle to take the boat and didnt want the motor. He knew nothing about the motor and had built some contraption of spliced hoses to try and start it. He also tried to sell me the boat lift in his backyard on the channel to the lake.The control box is actually still mounted to a piece of wood from that boat. I think he disassembeled the boat because he had parts in boxes. When i get it going i am going to put it on my 56 crestliner so its going to be pretty awesome. My crestliner is a closed bow type runabout. Ive been looking for a decent big twin for a while.
 

oldboat1

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interesting history (and kind of strange, huh?) Anyway, will be a nice rig with that Crestliner. You might try cleaning the spring connectors in the boots first to make sure there is a good connection with the plug/tester. Source for corrosion. You probably have the right idea re wires (replacement), but could try reattaching the spring connection first to make sure there is good contact with the wire. If the coils were replaced, it's possible that the wires were not placed properly at the coils (would need to get at the coils to fix that, and then might as well do the new wires). One thing you might try -- Use a continuity tester between the boots to see if you get a connection -- should be ground continuity I think if all is connected (incl. the wires at the coils).
 

JoeFromAkron

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Maybe Im thinking wrong but wouldnt both the breaker points have to be closed at the same time for that to work? I never thought of using a continuity tester but i would think i could test between the boot and the wire that goes to the breaker from the coil to test if its all connected? I cant even pretend to know what im really talking about though.
 

JoeFromAkron

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And the coils are much newer. I was pleaantly surprised but why someone would change those and not the spark wires is confusing. One of the wires is actually taped up.
 

oldboat1

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You might be right about the continuity test, but think there would still be a common ground through the plate. Should be able to test as you describe if the flywheel is pulled. But I like the appeal of testing the whole circuit without any fuss or bother (maybe should try it on the '56, and see if the test works).

Agree on the wire replacement thing. Maybe it was an availability issue -- think you are probably on to the spark problem if one is taped up. Need the 7mm wire with solid wire core -- think somebody mentioned it's used in tractors or similar, so that would be a clue for sources. I get it at NAPA, but live in an upstate farming community so maybe that's why they carry it. (test your wire for continuity at the taped/spliced point).
 

oldboat1

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Shoot. Handy dandy shadetree idea of testing continuity between boots is bogus. Tried it with known good CD ignition and an old magneto motor. Useful for individual connections in the system of course, and I use the continuity tester often when troubleshooting. Probably an issue of primary vs secondary windings in the coils, or the issue of open/closed points. Not sure.
 
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JoeFromAkron

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What I was thinking was to test between the two areas in the red clouds for east set. I think that would show if there is continuity between the coil and spark plug boot irregardless of if the points are closed of not. This motor has a big inspection hole so I think I can reach all of this without taking off the flywheel.
 

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oldboat1

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Try it. If that works, know you have a pass through at the coil, and a test for coil wire continuity. But unfortunately would want to try it with a known good magneto first -- not sure if your 15 has that view plate or not (and would be kind of a pain, anyway, to take off the hood and the recoil starter bracket to even get at the flywheel). When you pull the flywheel on the 25 and put in new wires, would be good to try out the continuity test for future reference. All interesting.
 

oldboat1

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wouldn't come out with the gearcase -- should remain up in the leg (fits into the grommet on the water pump housing). But I haven't worked on the '53, so could be a different animal.

edit. working from recall (always dangerous), but believe the tube on my '57s could be removed from the grommet at the powerhead -- pushed them back up there if they came out with lower unit removal. So would expect yours would be similar. Tube would likely stay up in the grommet at the powerhead.
 
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JoeFromAkron

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I was looking at the diagram and it looks like it just pushes the water through a passage to the water pipe? It dosen't look like it goes into the water pump like "newer" ones. That would make it easier to get back together maybe.
 

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JoeFromAkron

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wouldn't come out with the gearcase -- should remain up in the leg (fits into the grommet on the water pump housing). But I haven't worked on the '53, so could be a different animal.

edit. working from recall (always dangerous), but believe the tube on my '57s could be removed from the grommet at the powerhead -- pushed them back up there if they came out with lower unit removal. So would expect yours would be similar. Tube would likely stay up in the grommet at the powerhead.
My 15 hp was like that.
 
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