[Search for users] [Overall Top Noters] [List of all Conferences] [Download this site]

Conference vicki::boats

Title:Powerboats
Notice:Introductions 2 /Classifieds 3 / '97 Ski Season 1267
Moderator:KWLITY::SUTER
Created:Thu May 12 1988
Last Modified:Wed Jun 04 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:1275
Total number of notes:18109

569.0. "Johnson 40hp outboard problems" by WOODRO::EDDINGS () Thu Dec 14 1989 10:22

         I have a major problem with a Johnson 40hp from the mid 70's.
    When i go to start it either gas comes pouring out of the carb,
    or it does not get any gas at all.
         The other problem is with the electrical.
    Sometimes it turns over with the key, but most of the time it won't
    so i have to jumper around the starting soliniod to ground.
    
         If anyone has any ideas, or somewhere i can bring it to be
    fixed, please let me know. (most dealers won't take it because
    they only work on the ones they sell.
    
    thanks
    
    john
    
T.RTitleUserPersonal
Name
DateLines
569.1Do it yourself and $aveNRADM::WILSONA man's place is on his boatThu Dec 14 1989 11:0543
RE: Note 569.0 

>> I have a major problem with a Johnson 40hp from the mid 70's.
>> When i go to start it either gas comes pouring out of the carb,
>> or it does not get any gas at all.

Sounds like a sticky needle valve in the carb, sometimes sticking in
the open position, other times in the closed position.  It could also
be combined with aged or cracked gaskets in the carb.  At the times
that the needle valve opens the gas would leak out.  Solution: Overhaul
the carb.  Also check for cracked/leaky/kinked fuel hoses.


>> The other problem is with the electrical.  Sometimes it turns over 
>> with the key, but most of the time it won't so i have to jumper 
>> around the starting soliniod to ground.

Sounds like a bad connection at the solenoid or a defective solenoid.
Solution: Remove each of the wires, clean thoroughly and reconnect.  
Your solenoid case may also need to be grounded, so clean the mounting
bracket or ground strap if there is one.  If still no go, get a 12v 
test light or meter.  Check to make sure that 12v is being applied to 
the small wire on the solenoid when the key is turned to start.  This 
should in turn close the solenoid and allow 12v to flow directly from
the battery to the starter.  If you don't see 12v on the small wire when 
the key is turned to start, check the ignition switch and wiring.  If 
you've got juice at the solenoid but it will not close then suspect a 
bad solenoid.

>>  If anyone has any ideas, or somewhere i can bring it to be
    fixed, please let me know. (most dealers won't take it because
    they only work on the ones they sell.

Are you asking for advice on how to fix these problems, or just looking 
for a good shop to take it to for repairs?  Neither of your problems is 
anything major that you can't fix yourself if you're reasonably handy
and patient.  You should also be able to save quite a few $$$, because
most dealers will soak you for big bucks for a carb rebuild or a new
carb.  The electrical problem is most likely so simple there's no reason
you shouldn't at least try it yourself.  If you have any doubts, try to
get a friend who is familiar with this stuff to help you out.

Rick W.
569.2sound like an interlock switch is badBIZNIS::CADMUSThu Dec 14 1989 14:5470
    
    
    RE .1
    
     I agree with the first point- sounds like the carb needs rebuilding-
    before I got into that- you just may be all gummed up, so I would drry
    running some gumout through the engine- especially if it's been sitting
    with old gas/oil mixture which tendds to turn into glue as it ages. It
    could also be a result of water in the fuel- if the gumout doesn't do
    it,then rebuild the carb- it's pretty simple on these old 40's.
    
     AS to the solenoid- there is s satrt interlock on this engine which
    prevents you from starting in gear with the throttle advanced (it can
    get thrilling when this is bypassed)-Check the solenoid- if there are
    two small wires , trace them out- one should go into the wiring harmess
    and the other probalbly goes to either a ground or to aan inetrlock
    switch on the engine that prevents starting in gear.
    
     There is an interlock switch in the throttle/shift control housing
    also.
    
    To test:
    
    first- Remove spark plugs and ground the magneto(s)- so it can't start!
    
    Then:
    apply + 12 volts to the terminal on the solenoid that goes into 
    the wiring harness- if the solenoid  pulls in,,but it won't with the
    key,the problem is in the control box interlock. If it doesn't pull in and
    you have a two wire solenoid, trace the wiring  back to the engine and 
    bypass any switch in the circuit- either the interlock is activated
    ( it ain't supposed to start) or the interlock switch is bad.REPLACE
    any bad interlock switches- don't bypass them! 
    
    The problem is one of  things:
    bad solenoid (improbable)
    dirty connections (possible)
    bad interlock switch in control housing(probable)
    bad interlock on engine or bad ground (very probable)
    INterlock acuated(trying to start while in gear (sometimes called a
    D.S.)- it's supposed to do this
    
     On the manual start 40's the interlock is mechanical to prevent
    starting while in gear at high throttle settings. On the electric start
    motors this is done electrically. Starting an engine while in gear at
    wide open throttle while standing in the stern of a skiff can be a
    thrill- I was in a borrowed skiff and watched my then teen age son do
    this- by time he hit the water, the skiff was almost airborne- what A
    thrill I had getting to the stern to kill the engine.
    
     If your problem is a bad interlock-fix it- it could save your life
    or prevent a serious lawsuit. I had a freind who managed to start
    a 10 hp O/B on a small alum. boat while the engine was full throttle
    forward. His comapnion had not been taught anything about using the
    engine. He went over the stern as soon as the engine started, and by
    time she got control of the boat,figured how to slow it down and stop
    it- he was gone. Coroner's report indicated he had most probably gotten
    hypothermic and then drowned.
    
     Just some words of caution- it is real easy to bypass an interlock
    (which I suspect is your problem), but they are there for safety-
    if the problem is a bum switch or linkage- Fix it, don't bypass it.
    The reason I suspect an interlock switch is beacse it is intermittent-
    dirty/corroded connection tend not to be intermittent.
    
    my 2� for waht it's worth
    
    Dick
    
    
569.3thank for the infoWOODRO::EDDINGSFri Dec 15 1989 12:445
    Thanks for the info.  I'll give it all a try. (If the weather ever
    gets warmer)
    
    thanks