1989 Johnson 50 ?'s

ob15

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Jan 4, 2004
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Hope you don't mind me starting a new post about this motor. I figured I would start a new one because I bought the motor last night and would like to start fresh. First off I will list the model No. & then some questions I have.<br /><br />1989 Johnson 50, Model No. J50TLCEC<br /><br />I have some question that I can not get from my Clymer's manual and have a reply from TheOutBoardWizard.com for a shop manual, which I am definitely going to get. Ok, Now for the questions.<br /><br />I was reading the Clymer manual and it mentioned that the 89 & 90 48 & 50 hp models came with the CD2USL ignition system which includes the SLOW system & rev limiter. Is this correct?<br /><br />Also It would be greatly appreciated if someone could tell me what the gear ratio was and the charging output of the stator/rectifier.<br /><br />In most of the post I have read, when the rpm range is listed by OMC as 4500-5500 (and I am assuming this to apply to this motor), it seems that 5800 is the magic number. Just another question for confirmation.<br /><br />Are there and quirks with the T&T units on these motors?<br /><br />Now for the biggy. As some of you may have read my post prior to me buy this motor ( http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=28;t=028348 ), The seller mentioned that it would jump out of gear at appox 30-40% throttle. I questioned him about it wondering if it might be the prop spinning the hub or the clutch dog. He told me that when it got up to about that throttle range it would just pop out of gear and nothing else. The motor rpm would not change and there were no noises. This made me think a little (I don't know how bad or good that is). To me it would seem that if the clutch dog was bad, the motor would want to jump in and out of gear constantly making a terrible noise. Obviously the prop hasn't spun its hub because there was no rpm increase. Is this a correct assumption and if so, could it be in the linkage somewhere or maybe old cables or controls (I do have all new controls and cables on my boat)? I am by no means very knowledgeable about outboards and maybe my common sense should not apply to this situation but I’m an engineer and can’t help over analyzing things. I am going to try to get the motor rigged on my boat this weekend and give it a brief water test to confirm the above symptoms. In the mean time any suggestions or helpful hints would be greatly appreciated. Once I can figure this out, I’ll do the prudent maintenance things (clean carbs, new water pump, replace gear lube, etc.). <br /><br />BTW. The motor was previously on a 16 Carolina skiff if that helps at all.<br /><br />Once again, thanks and I will definitely be adding to the thank you post very shortly.
 

DHPMARINE

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Dec 16, 2003
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3,688
Re: 1989 Johnson 50 ?'s

Dave,<br /><br />We are not here to tell you if the Clymer manual is correct or not.They have proof readers that do that.<br /><br />I don't think the gear ratio or charging output will help you with this problem.<br /><br />You need to water test this engine and get back to us.If the prop slips,or the motor 'pops' out of gear at any rpm I'll guarantee the rpm's go up.<br /><br />So get back to us and let us know what's really happening.<br /><br />DHP
 

ob

Admiral
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Aug 16, 2002
Messages
6,992
Re: 1989 Johnson 50 ?'s

The charge output of the stator should be around 18-20 volts.The reg/rec output should be around 13-14 volts at 2500 rpm and up.That engine would run just fine propped to turn 5500-6000 wot.No quirks that I am aware of on the tilt /trim unit.Keep your tilt bracket bushings greased regularly,and clean the rams every so often and keep a light coat of machine oil on em.<br /><br />Not sure whether that year model had the S.L.O.W system,rev limiter.or quickstart feature.If I had to guess,I'd say that 89' didn't have the s.l.o.w. system.But then that's just a guess.Follow the books wiring diagram from the engines temp sensor to be sure.<br /><br />Gear ratio is 12/29 which translates to 2.416 rounds of the crankshaft to 1 turn of the propshaft or .414 rounds of the propshaft to one turn of the crankshaft.<br /><br />Be looking forward to your watertest results.Hate to even speculate until you can give us some details of the problem symptom.Off hand it sounds like shift dawg and/or gear lobe wear.It which case as DHPMarine states,would cause a momentary rise in engine rpms as the unmeshing gears unload the engine.
 

ob15

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Jan 4, 2004
Messages
514
Re: 1989 Johnson 50 ?'s

Thanks guys' I'll let you know what I come up with. ob, I should have phrased the charging output question better. I was just wondering what the charging amps were.<br /><br />Thanks again!
 

Walker

Captain
Joined
Jun 15, 2002
Messages
3,085
Re: 1989 Johnson 50 ?'s

Dave, before you ever put it in the water I'd make sure the shift linkage is moving fully into the forward position. Could be as simple as stretched shift cable and every time the gear/shiftdog slips your are wearing out the mating surfaces.
 

ob15

Chief Petty Officer
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Jan 4, 2004
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Re: 1989 Johnson 50 ?'s

That's one thing I thought of and will definitely be checking that after I hook it up to my new controls
 

rodbolt

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Sep 1, 2003
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20,066
Re: 1989 Johnson 50 ?'s

hello<br /> your eyes can tell you very rapidly wheather or not you have a cdusl or a cdsl<br /> the u indicates its under the flywheel. if your pack is located on the stbd side of the block its not a cd2usl:)<br /> not to bum on engineers but most trust books to much and the eyes and common sense to little. trust your eyes.<br /> and yes virginia, it is possible to have a clutch dog slip without a noticable change in RPM. however it feels like someone it the transom with a baseball bat.and usually about the 3rd slip the fwd gear and clutch are toast.<br /> i just had to replace them in my 115spl :( .<br /> so mount it up and go play. I have one of the 48's out back someplace :) <br />does yours have electric/hydraulic T+T or is it the gas assisted touch trim ?
 

ob15

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Jan 4, 2004
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Re: 1989 Johnson 50 ?'s

Thanks rodbolt,<br /><br />It's raining right now so as soon as it clears (hopefully), I will be checking it all out. It does have the electric/hydraulic T&T.
 

rodbolt

Supreme Mariner
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Sep 1, 2003
Messages
20,066
Re: 1989 Johnson 50 ?'s

hello<br /> the elec version was very reliable. the cd2usl was not. had a tendancy to trigger slow for no apperent reason sometimes. get her mounted and hooked up and tell us how it does:)<br /> make sure you have an accurate tach for testing.<br /> cross your fingers on the clutch dog
 

ob15

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Jan 4, 2004
Messages
514
Re: 1989 Johnson 50 ?'s

Thanks again rodbolt. The weather's been pretty rainy all day. Hopefully I can get to it tomorrow. Got a tinytach so checking the rpm's is no problem.
 

ob15

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Jan 4, 2004
Messages
514
Re: 1989 Johnson 50 ?'s

We'll I got the motor mounted but that was it. I hope to finish it next weekend. Have to get an impact driver to take apart the old control box and a few other things.
 

ob15

Chief Petty Officer
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Jan 4, 2004
Messages
514
Re: 1989 Johnson 50 ?'s

I finally got to water test the motor and the bottom end is fine. The prop spun the hub. That certainly saves me a bunch of time. The motor has a bunch more power that the old 80 rude had. I used the prop from the old rude (11 3/4 x 17) and before I knew it the rpm's were at 5900 and that was only about 3/4 throttle (maybe a little more). I was very surprised at the additional power. The prop that spun the hub should work great, its a 3 bladed SS prop (11/14 x 19). <br /><br />I'm having another problem with the motor but I will start a new thread for that.<br /><br />Thanks again for all the help and advice.
 
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