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1991 Johnson 40 start problem (pulling my hair out over this one!!!!)

R

ripperace

Contributing Member
In other words.....HELP!!!!!

Here's a good one! I've got a 91 Johnson 40 that has a start problem..... We'll start off by stating that someone had taken the keyswitch out of the control box to mount it in the center console.... So I made that right by reinstalling the keyswitch in it's proper location, and changing the switch as it looked like someone held onto the body of the switch with a pair of channel locks. No start. Double checked the wire positions, still no start. Check battery voltage, reads good at 13.6 volts. Clean the connections, and make sure they're tight. Still no start. See that someone had hacked into the wiring harness from the switch to the motor, so I swapped it out with a NOS one. Still no start. Check for voltage back at the solenoid to see if it was getting voltage back through the system. CHECK! Go through the entire check list as per the OMC manual for that motor, and EVERYTHING checks out until you get to number 7 on the check list. I get 2.3 volts at the starter, the solenoid sounds like it's going to hop apart because it's trying to get voltage to the starter, but can't (rat ta tatatatatatatatatatatatat. You get the idea.) So I figure the starter wasn't grounding, so I pull it off, clean the connections on the block and starter mounts, and reinstall the starter. Still nothing! Take the starter cable off the solenoid and test for voltage. Solenoid is operational, and getting 13.5 volts at the starter cable ring terminal that mounts to the starter motor lug. So I open the starter up. Magnets inside are cracked. OK, buy a new starter. Install new starter. NOTHING! Solenoid still sounds like it's going to rattle apart. So I swap out the solenoid to starter cable. Still doing the SAME THING! I've cleaned every connection on this motor, on the battery and cables, checked the keyswitch as per the manual, even went as far as swapping out control boxes thinking there was something funky with the harness. STILL NOTHING! The replacement starter motor will operate on the ground with one wire grounding the case, and the other going to the battery, but once you bolt it to the motor, it's got nothing. Everything checks out until you bolt the starter to the powerhead, and hook the battery cable up from the solenoid to the starter. I've even swapped wires around on the solenoid thinking that might make a difference. STILL NOTHING except the solenoid sounding like it's going to rattle apart.

I'm really scratching my head over this, and wonder where to go from here, because I'm out of thoughts. :mad:

Any ideas? Anyone, anyone? Bueller, Bueller?

Ripper
 
I would check your solenoid most people don't realize that there are two parts to the solenoid. Just because the power to it tests correct doesn't mean its operating correctly. The low amperage part that comes from the key switch which energizes the solenoid to push the down the disc to let the line amperage through. Two different electrical sources there if one goes bad thats the sound they make or you have a problem with the neutral safety switch or ignition switch.
 
That's what I thought too after I wrote the initial post, so I changed it with a new Sierra solenoid. Still got the same issue. Solenoid will energize as long as it's not hooked up to the starter. Once I hook the starter back up, same deal. Solenoid sounds like it's going to rattle apart. So I pulled the starter back off and hooked it up to a jet ski battery that held 11.2 volts. Starter motor would spin, Bendix would jump up, no problem. So the next step was to bypass the solenoid and see if the starter would spin once mounted back to the power head. Got absolutely nothing. Next step would be pull the battery cables from the motor to the battery (some genius ran them under the floor) and see if swapping them for a shorter set would do any good. Still scratching my head.....also checked the neutral start switch, and it was good. As I'd mentioned, I'd swapped control boxes with one I know was good, and still have the same thing going on.
 
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check the cable between the solenoid and starter and when the cable is off turn the key and see what the voltage on the starter side of the solenoid without the starter attached.
 
13.5 volts. Then if I hook the cable back up to the starter I get between 2 and three volts at the same spot. That's what lead me to believe the starter was junk in the first place, so I replaced it with an ARCO starter. No difference. I even changed the cable from the solenoid to the starter with no difference. That's why this is so frustrating. I'd originally thought through my testing that it was loose or dirty connections, and that's how this whole scenario started. No matter what I've checked, then swapped, it made no difference. The only thing I can think to do is load test the battery, then swap the main battery cables to see if it isn't getting amperage. I find that hard to fathom as the battery isn't two months old, and the cables look like they've been replaced at some point.
 
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Absolutely. Anywhere there was contact made from a wire to wire, terminal to terminal, and both grounds (the solenoid ground, and main ground) had been cleaned.
 
hook everything up normal....hook the negative lead to a good ground on the motor.. at this point with the motor just setting there with the key off you should have battery voltage on the source side of the solenoid....12.6 or close to it...there should be zero volts on the starter post....have someone turn the key to start...the solenoid should pick and you should see voltage on the battery post....the amount of that reading is important....write it down to the tenth of a volt...then do the procedure again with the start key and get a reading off the positive post on the battery...write the reading down....move your negative lead to the negative post on the battery and take a reading between the two battery post with the start key engaged..move your positive lead back to the starter post...the negative is still on the battery...go through the deal again with the start key turned to start and write the reading down...get back to us with the readings please..

do not hold the key to start any longer than you have to to get the readings...
 
reread your thread....the 2 volts or whatever thats on the starter post without the solenoid picked is wrong...it needs ground feeding from the motor through the starter and then when solenoid picks the circuit is complete from battery positive through the motor to ground...the first thing to do is to make sure the motor is actually at ground.......if this is ok then you have a wiring error...
 
lets do a static test on motor grounding...set your meter on rx1 scale and zero it if needed..disconnect the big cable from the negative post on the battery and read from the battery end of the wire to motor ground..should read zero...connect the lead back up....now take a reading across the battery posts...then take a reading from the positive post on battery to motor ground...should read the same..
 
we will know if the battery is bad from the readings....but before anything else you have to find out why and correct that voltage on the starter post...
 
papyson said:
hook everything up normal....hook the negative lead to a good ground on the motor.. at this point with the motor just setting there with the key off you should have battery voltage on the source side of the solenoid....12.6 or close to it...( 12.23 in reality) there should be zero volts on the starter post....have someone turn the key to start...the solenoid should pick and you should see voltage on the battery post....the amount of that reading is important....write it down to the tenth of a volt...(.228 volts)then do the procedure again with the start key and get a reading off the positive post on the battery...write the reading down....(3.12 at the batttery) move your negative lead to the negative post on the battery and take a reading between the two battery post with the start key engaged..(12.02 between battery terminals)move your positive lead back to the starter post...the negative is still on the battery...go through the deal again with the start key turned to start and write the reading down...(8.93)get back to us with the readings please..

do not hold the key to start any longer than you have to to get the readings...
Click to expand...

Readings I got are listed in parenthesis.
 
papyson said:
lets do a static test on motor grounding...set your meter on rx1 scale and zero it if needed..disconnect the big cable from the negative post on the battery and read from the battery end of the wire to motor ground..should read zero...(reads .1) connect the lead back up....now take a reading across the battery posts...(Reads open)then take a reading from the positive post on battery to motor ground...should read the same..(reads open as well)
Click to expand...

Readings are in parenthesis.
 
Found it! I'll post pics when I get them off my phone. Let's just say someone was a sheer genius. The main battery cables had ring terminals on them. Someone had added extension wires to make them longer and run them under the floor. Apparently they did this BEFORE they installed a new floor. They had the extension cables bolted together and fastened to the stringers. Which is why I had a helluva time pulling them. SO, they fastened them together with regular steel bolts, sheathed in bilge pump hose, and wrapped in electrical tape........ Why they didn't get the extra 4 foot of new cables and run one peice rather than thinking two cables bolted together would be "just fine" is beyond me.
 
good show...the readings showed a battery lead problem also...primarily with the negative lead...

your battery reads low also....either not charged or time to replace it.
 
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