1956 Johnson javelin 30hp

gragger

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Jun 15, 2007
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Hello all, I've been coming into read some of questions answered by all of you, you know what I found? That your all alot smarter than I...
I'm new to boating, and boat motors, I've come across a chrysler boat, with a 1956 Johnson javelin 30hp outboard. so I think it is, Model number rje18c.. if someone could be so kind to verify that for me please...
Also, I can start the motor, however, it does backfire and ClAnG or KnOcK, I'm not sure what this is, I've got spark on both cylinders, I've timed them both, I was under the impression that it could be due to timing, but, I'm NO guru..... could it be a bearing, it doesnt knock or clang all the time its running, however, every couple seconds, or five seconds, its not constant though... I would greatly appreciate any words on diagnosing this problem.. Of coarse, I would rather try ALL options first other than taking the motor apart, unless, this is what it has to be,, thank you to all that respond...
 

tashasdaddy

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Re: 1956 Johnson javelin 30hp

tell me what you have done, when you say you have timed them both. are you running it with the leg submerged in water 1/2 way up? i just redid a 58 35 hp.
 

BoatBuoy

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Re: 1956 Johnson javelin 30hp

Johnson Javelin RJE18 - one of my favorites. Have one myself.

Sounds like it may be running lean. Check this for carb jet settings http://forums.iboats.com/showthread.php?t=167352 . You want to eliminate as many sources as you can for knocking. Sparkplugs should be Champion J6C gapped at .030. You should check the compression. That is a pretty good indicator of internal health. Let us know.
 

gragger

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Re: 1956 Johnson javelin 30hp

I have timed them both, meaning, found tdc and set my points at .20 while timing was advanced, correct? Yes, shaft is under water to allow proper cooling...
 

gragger

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Re: 1956 Johnson javelin 30hp

Thank you boatbuoy, I have trouble starting the motor without touching those darned jets....lol,,,, everytime I try to adjust these things, the motor starts kicking and knocking... however, the thought of compression testing is prolly the best thing for me to do at this time..... that'll tell me just how each one is doing... great suggestion, I didn't think of doing it, cause, well, I dont have a compression tester, however, I'll get my hands on one, and let you all know... thank you both for your suggestions and concerns.... please keep'm coming...

Thank you ALL.....
 

samo_ott

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Jun 18, 2006
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Re: 1956 Johnson javelin 30hp

All the old engines usually need coils also... what shape were yours in? And maybe a carb kit?
 

gragger

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Re: 1956 Johnson javelin 30hp

samo, with this being my first boat motor,,,,, I'm really not sure what shape their in, however, they do not LOOK worn, nor is the insulator around the wire have any cuts or tears....
 

Chinewalker

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Re: 1956 Johnson javelin 30hp

If the coils show no cracking or chalky residue, they have already been replaced. Most of the coils replaced since the 1970s have the newer style coils that hold up much better. For gapping the points, set them at .020 with the cam rider aligned with the crankshaft keyway. Doesn't matter how "advanced" the timing is, it is self-timing once you gap the points.

Your other issue does sound like a lean sneeze. Can't really adjust it perfectly until you get it on a boat and out of the barrel. If you can't adjust it out, then you likely have a gummed up carb. Take it apart and rebuild it, with attention to cleaning all passages and orifices.

- Scott
 

gragger

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Re: 1956 Johnson javelin 30hp

Boat Buoy, thank you so very much, and to the rest of you as well, it turns out, I'm no longer wondering what that knocking is, I dont know exactly yet, however, with the compression test, I do know that it is in my top cylinder.... Until I tear it down, good luck to all, I'm sure after I get it done, I'll be asking more questions... thanks again. by the way, how does one determine the year trailer and boat itself, I've got model and serial for trailer, M= c-100 S= 5020 2501, and the boat serial is 360301197, I was told that they were all original together, now I fail to believe that, only because I was told it was a 1967, which obviously, the motor isn't...
 

gragger

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Re: 1956 Johnson javelin 30hp

Hello again, before I start this project, where can I get internal parts for this beast......lol
 

Chinewalker

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Re: 1956 Johnson javelin 30hp

If you have a very long-established Johnson/Evinrude dealer nearby, they might have some parts in stock. Otherwise, you're probably looking for used parts, or maybe something from Twin Citys Outboard up on Minnesota. Seaway Marine out in Seattle also handles older motor parts. Sources for parts beyond the consumables for a 50+ year old motor are few and far between.
- Scott
 

BoatBuoy

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Re: 1956 Johnson javelin 30hp

You might do as I did for my '57 Javelin (yea, I've got one of them too) that had a scored cylinder wall . I found a good used powerhead and just put that powerhead on it. As Scott said, internal parts are scarce. It doesn't have to be a Javelin, any '56 30hp Seahorse will work. I had good luck posting a free wanted ad over at the aomci webvertize site http://www.aomci.org/cgi-bin/adshow.pl?PERPAGE=25&OFFSET=1 . You might also want to acquaint yourself with aomci.org, site specializing in antique outboards.
 
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