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2001 jhonson 70hp hard cold start

outback32

Regular Contributor
I have a 2001 jhonson thats very hard starting cold. It just cranks and cranks
seems like its going to run the battery down. when it finally starts it will run all night. I can stop it for hrs and it will fire right up its just the initial start up.
 
Proper Starting Procedure:

Pump fuel primer bulb until it is hard.

Turn key to the START position and push the key in and hold it there while cranking.... Pushing the key in engages the Fuel Primer Solenoid <-- Look upon this as a choke action.

When the engine fires, starts, let go of the key which will drop to the ON (run) position.

Now... Which of the above aren't you doing?
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In case you weren't aware of the Fuel Primer Solenoid's function, read on.
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(Fuel Primer Solenoid Function)
(J. Reeves)

The RED lever...... The normal operating/running position is to have that red lever positioned over top of the solenoid and aimed at the other end of the solenoid, gently turned to its stop. This is the normal/automatic mode position. Pushing the key in opens the valve within the solenoid allowing fuel to pass thru it in order to prime and start the engine. Looking upon this solenoid as a electric choke results in a better understanding of it.

Having that red lever turned in the opposite direction, facing away from the solenoid, allows fuel to flow thru it to the crankcase area. One would only turn the red lever to this position in a case where the battery might go dead and the engine had to be started via the rope pull method. Look upon putting the red lever in this position as moving a choke lever on a choke equipped engine to the full closed position. Either one would supply fuel to the crankcase/engine for starting purposes BUT if left in that position while running would flood the engine.

The later model primer solenoids are equipped with a schrader valve, used for attaching a pressurized can of fogging oil etc, available at your local dealership with complete instructions.

Pumping the fuel primer bulb up hard fills the carburetor float chambers of course, but that process also applies fuel pressure to the primer solenoid.

The two small hoses leading from the primer solenoid branch off via tees to each fuel manifold section that would feed fuel to the individual cylinders.

Pushing the key in activates the primer solenoid to allow fuel to flow thru it to the intake manifold passageways. Cranking the engine over causes the fuel pump to engage which in turn sends fuel pulses to the primer solenoid via the 3/8" fuel hose.

Some engines incorporates the "Fast Start" feature which automatically advances the spark electronically so no advance of the throttle is required for starting.
Engines that do not have the "Fast Start" feature will be required to have the throttle advanced slightly.

Starting procedure: pump fuel bulb up hard, crank engine and push the key in at the same time. When the engine fires/starts, release the key so that it falls back to the run position.

Bottom line..... Look upon the primer solenoid as an electric choke.

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I found the starting procedures before I made this post. I followed the procedures I push the key in while cranking. is there any other reasons why it would be hard starting
 
Flywheel must spin fast to generate spark.-----Starter motor just has to be in good condition !!-----Battery has to be in good condition.-----So pull the starter apart for inspection / new brushes.----Do an ohm test on it.-----Get battery load tested at your local battery seller.
 
The engine must crank over at least 300 rpm in order for the stator to energize the powerpack's capacitor. A slow cranking engine will result in weak, erratic, and eventually no ignition.

If your engine is cranking over at a normal fast rpm, I would strongly suspect that the fuel primer solenoid is faulty, is not engaging when you push the key in due to either...... it's jammed for some reason... OR... it is not receiving the 12v needed for it to engage.

Let us know what you find.
 
well I took it out 2 weeks ago to Kentucky lake and it did great. took it out today and it wouldnt start. got it home and I have no fire on any cylinder. battery is completely charged i have a new 3 bank charger that i charge all the batteries with.
 
Some will argue.-----I would take the starter apart for inspection ./ new brushes perhaps / ohm check from commutator to the shaft.----Should read infinity.-----Easy work and costs ZERO $ to do an inspection.----No need to rush out to buy a new one.----Inspect first.-----Kill switch is in the right position and working properly I hope.
 
Remove sparkplugs.-----Pull connecter apart in wiring harness that has the black / yellow stripe wire.----Pull flywheel with a rope.-----Do you see spark now ?
 
well im kinda confused now. I unplugged the connector
with the yellow and black wire. jumped the solenoid and had spark so i plugged it back in. tried with the key and had spark and the engine starts and runs great. the only things i did was try to take the keyswitch out of the console and unplugged the connector and jump the solenoid. im confused as to why it has fire now and i didn't do anything.
 
The next time this takes place... if ever, remove the black yellow wire from the ignition switch. If that returns the spark immediately, replace the ignition switch as that normally indicates a intermittent connection (short) within the ignition switch that allows a mi-nute amount of voltage to interfere with the kill circuit.
 
Thats what I was wondering if it was something to do with the ignition switch I was trying to take it out but it wouldn't come out. so i thought maybe there was a loose connection in there. thats the only thing i really did that i could see making a difference
 
Thats what I was wondering if it was something to do with the ignition switch I was trying to take it out but it wouldn't come out. so i thought maybe there was a loose connection in there. thats the only thing i really did that i could see making a difference

Is it contained within a regular white OMC type control box, a more or less chrome top console single lever control, simply attached thru a hole in the dash or console?

I'd suggest looking thru the parts listing (Top Of Page) of whatever you're working with to get a idea of how things come apart/go together. Be sure to disconnect at least one terminal of wires off the battery to avoid expensive sparking!
 
its a regular omc control box. do you think the intermittent no spark is in the key switch. I was told it was replaced last year. Also the times it was hard to start and just cranks. im wondering now if its not sparking because im following the start method. I don't think its fuel related
 
its a regular omc control box. do you think the intermittent no spark is in the key switch. I was told it was replaced last year. Also the times it was hard to start and just cranks. im wondering now if its not sparking because im following the start method. I don't think its fuel related

You cannot guess about this. You need to determine exactly if you have spark or you do not when this problem occurs.

When the engine cranks and does not start.... Be prepared to remove the spark plugs... Attach a spark tester of the type whereas you can have a "Air Gap" of 7/16" for the spark to jump across... The spark should be a strong blue lightning type flame, a real SNAP!

If no spark is indeed the problem... remove the black/yellow wire from either the ignition switch or the powerpack... If removing this wire has the spark returning immediately, the ignition switch should be replaced.
 
well the no spark has returned. I took the wire off the switch and it made no difference. I rab down all wires and coouldnt find any bad wires. so I have a intermittent no spark situation. is there any way to test the cdi box. or what else could it be thanks
 
The stator under the flywheel is the beginning of both the battery charging and ignition system.

Check the ohm reading as per your service manual of the brown & brown/yellow wires that lead to the powerpack.

Should there be any sticky looking substance dripping down from the stator upon the powerhead area, replace it regardless of what readings you may obtain from it.

Check all of the rubber plug connectors as the pins/sockets have been known to back out slightly which results in a poor make/break type connection.... also the wire has been known to break away from the pin/socket BUT the wire would be held within the connector by sheer friction, giving the illusion of a proper connection.

There is a site whereas one can find instructions to check the pack but I can't think of it at the moment, sorry. I'm sure another member will jump in here with that info shortly.
 
I ended up taking it to a mechanic. he called and said when he got it it had no spark. during his testing the spark returned. but he cant do any further testing until it fails again. so im back to square one I really don't have much faith in the spark staying
 
Maybe the black/yellow wire is shorted along it's route. Perhaps that is why someone previously had tried with a new ignition switch and it may have worked for a while. Have him try and disconnect the black yellow wire at the powerhead, test with his multimeter and make sure it is not shorted to ground. Have him do this with the motor in all positions.
 
He called yesterday told me it was fine to come pick it up. so i drove up there this morning. wanted to test it before i took it home. of course no spark really wish he wouldve tried it before i drove up there. but now its not getting spark again he can keep testing at least
 
mechanic called said it was the timer base. charged 243.00 for the part I looked it up and could get it for 175.00. it ended up costing me almost 500.00. wifh I could've figured it out on my own
 
Since the timer bases are constantly rotating back and forth often time the damage is only a wire. The problem is many people test them only in one position but you have to test the timer base while moving the throttle through its entire range of motion.
 
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