No power to start motor or tilt on 48 hp Johnson

[Sea-Girl-in-Paradise]

Hello. I am wondering if anyone can help trouble shoot an issue I am having with my 48 hp Johnson 1990 motor. I put a new battery in and checked the power shut off switch. Once in a while, I can trim the motor but only up or down once then it won't tilt again. Also, the motor will not start at all like their is no power. I am looking for the motor fuse now but have not found it yet. Any ideas on any more trouble shooting?

 

[oldboat1]

Step one is to clean all connections until shiny bright (sandpaper). Start with the battery cables at the battery and see if that alone gets you going.

 

[racerone]

Find the fuse in the wiring harness.---Be near the starter solenoid.----Little black rubber plug holds it.

 

[Sea-Girl-in-Paradise]

Hello. Update, I found a fuse over behind the coils which appears ok from the meter readings but not one by the solenoid which I can't seam to find. I replaced the old terminals on the new battery. And still no power. I cleaned all the connections around the motor including the solenoid which is getting power from the battery. Not sure if the solenoid is getting power from the ignition. ok, just checked that and I am not getting power to the solenoid from the ignition. Is it the ignition switch?

 

[Crosbyman]

now you need to ascertain if the switch itself is receiving power. if not it can't send it to the selenoid. If it does get power ... bad switch or bad wire/power continuity back to the selenoid

consider possible neutral switch or other safety device interruptions

turn /hold the key to START have a buddy twist and wiggle all accessible wiring and... shifter
in neutral position

if you get a reaction you have a broken wire or shifter neutral switch issue.


since 2 issues T&T and selenoid are involved.. some diagrams show T&T directly powered without fusing whereas the power for the selenoid is fused ... the common point looks like the red BIG post wiring on the selenoid.... fat goes back to battery

make certain you have solid 12v and....CHECK grounding cable from bat to engine because 2 functions are dead and both need good grounding. check crimps...for oxidation

 

[Sea-Girl-in-Paradise]

now you need to ascertain if the switch itself is receiving power. if not it can't send it to the selenoid. If it does get power ... bad switch or bad wire/power continuity back to the selenoid

consider possible neutral switch or other safety device interruptions

turn /hold the key to START have a buddy twist and wiggle all accessible wiring and... shifter
in neutral position

if you get a reaction you have a broken wire or shifter neutral switch issue.


since 2 issues T&T and selenoid are involved.. some diagrams show T&T directly powered without fusing whereas the power for the selenoid is fused ... the common point looks like the red BIG post wiring on the selenoid.... fat goes back to battery

make certain you have solid 12v and....CHECK grounding cable from bat to engine because 2 functions are dead and both need good grounding. check crimps...for oxidation

Thank you. I will try your suggestions and let you know.

 

[Sea-Girl-in-Paradise]

now you need to ascertain if the switch itself is receiving power. if not it can't send it to the selenoid. If it does get power ... bad switch or bad wire/power continuity back to the selenoid

consider possible neutral switch or other safety device interruptions

turn /hold the key to START have a buddy twist and wiggle all accessible wiring and... shifter
in neutral position

if you get a reaction you have a broken wire or shifter neutral switch issue.


since 2 issues T&T and selenoid are involved.. some diagrams show T&T directly powered without fusing whereas the power for the selenoid is fused ... the common point looks like the red BIG post wiring on the selenoid.... fat goes back to battery

make certain you have solid 12v and....CHECK grounding cable from bat to engine because 2 functions are dead and both need good grounding. check crimps...for oxidation

Hello: We got the motor to start by hooking directly to the battery cable. We got the trim to tilt by putting battery power straight to it. The ignition switch shows power coming from it but not going to the solenoid. So we directly ran a from the ignition to the solenoid and it did not start. Checked the neutral switch and it is ok. So at a loss. And now sometimes not getting power from the switch.

 

[racerone]

Checked the ground wire from wee post on solenoid to the block ?

 

[Sea-Girl-in-Paradise]

Hi again. I appreciate your suggestions. We replaced the wire from the solenoid to the block. Not sure what wee post is though?

 

[Crosbyman]

assuming a properly grounded selenoid directly apply 12v to the control post ... if no click selenoid is dead... as in open winding check with a VOM should be LOW resistance a few ohms

wee post is the other one ... one is grounded so the other receives 12v from the switch....it is just an electromagnet and needs both a grd and batt. to CLICK ON


the FAT posts are just a transit point from BATT + 12 ===> to starter when the selenoid clicks ON

if simply no battery from the switch ... track the wire by holding on START and flex all wires...... it is open along the way back to the engine or... interrupted by a safety device


unfortunately this does not explain why T&T does not work... without jumpering something else is wrong here....

 

[Sea-Girl-in-Paradise]

assuming a properly grounded selenoid directly apply 12v to the control post ... if no click selenoid is dead... as in open winding check with a VOM should be LOW resistance a few ohms

wee post is the other one ... one is grounded so the other receives 12v from the switch....it is just an electromagnet and needs both a grd and batt. to CLICK ON


the FAT posts are just a transit point from BATT + 12 ===> to starter when the selenoid clicks ON

if simply no battery from the switch ... track the wire by holding on START and flex all wires...... it is open along the way back to the engine or... interrupted by a safety device


unfortunately this does not explain why T&T does not work... without jumpering something else is wrong here....

Thank you. We know the solenoid works for we jumped it and the motor started rignt up. Good news anyway! We are going to try and replace the ignition switch which is cheap and then get down and dirty and pull the harness wires like you suggested. It can only be so many things, right. I will keep you updated. Thank you.

 

[Crosbyman]

don't change a good switch unless you are certain no BATT 12v comes out of it while in START mode ........ to drive the selenoid.

yet your quote. "The ignition switch shows power coming from it but not going to the solenoid. .. "

no sense in changing a good switch $$$ if your selenoid control wire "going to the solenoid. .." is open to the back end of the boat !


and what about your T&T issue fixed ???

 

[Sea-Girl-in-Paradise]

don't change a good switch unless you are certain no BATT 12v comes out of it while in START mode ........ to drive the selenoid.

yet your quote. "The ignition switch shows power coming from it but not going to the solenoid. .. "

no sense in changing a good switch $$$ if your selenoid control wire "going to the solenoid. .." is open to the back end of the boat !


and what about your T&T issue fixed ???

Hello. I understand. Tilt only works when by passing switch. Even though switch is getting power, we are not getting power running to the solenoid from the switch? Any ideas? I really don't want to pull the wire harness through the boat out, but I don't know what else it could be? Just rechecked switch. It reads good but no power to solenoid. Wire harness is next unless you have any ideas? All grounds and connections have been checked too.

 

[Sea-Girl-in-Paradise]

Hello again: Update: Pulled start wire harness and it's good. mmmm

 

[Crosbyman]

well ...we are turning in circles...

does the start switch receive +12v from the engine on the B+ pin
yes= GREAT no = find the 12V from the fuse wire

does the switch transfer +12 to the S pin feeding the selenoid control wire ?
yes= GREAT good switch no = BAD switch replace

does the+12v from the good switch START pin reach the selenoid control post ?

yes= GREAT the selenoid should pull up and start transferring BAT +12 to the starter because you tested the selenoid with a direct feed of battery

no= follow from the switch S pin +12v to selenoid post and find the break (wire broken, bad connector, neutral safety, ....?)

take an external piece of wire connect between the switch S pin and selenoid post and see if selenoid clicks on when you turn the key to start. ... it better click because it did of a direct battery feed.


if not... that 12V arriving at the key B+ pin is HIGHLY resistive and carries insufficient amps to activate the selenoid..... It may test 12v but without amps... it is ineffective. could be oxidized fuse socket , frayed wire/oxidized wire etc... put a fresh solid +12V from the battery on the BAT+12 switch post and retry. if wire to selenoid is OK selenoid should CLICK

sorry to ask again but you did clean all battery supply connections from both battery posts to engine connections . check crimps . flex all wires for a reaction

 

[Sea-Girl-in-Paradise]

well ...we are turning in circles...

does the start switch receive +12v from the engine on the B+ pin
yes= GREAT no = find the 12V from the fuse wire

does the switch transfer +12 to the S pin feeding the selenoid control wire ?
yes= GREAT good switch no = BAD switch replace

does the+12v from the good switch START pin reach the selenoid control post ?

yes= GREAT the selenoid should pull up and start transferring BAT +12 to the starter because you tested the selenoid with a direct feed of battery

no= follow from the switch S pin +12v to selenoid post and find the break (wire broken, bad connector, neutral safety, ....?)

take an external piece of wire connect between the switch S pin and selenoid post and see if selenoid clicks on when you turn the key to start. ... it better click because it did of a direct battery feed.


if not... that 12V arriving at the key B+ pin is HIGHLY resistive and carries insufficient amps to activate the selenoid..... It may test 12v but without amps... it is ineffective. could be oxidized fuse socket , frayed wire/oxidized wire etc... put a fresh solid +12V from the battery on the BAT+12 switch post and retry. if wire to selenoid is OK selenoid should CLICK

sorry to ask again but you did clean all battery supply connections from both battery posts to engine connections . check crimps . flex all wires for a reaction

Yes, we did clean up all battery supply connections. Actually, we replaced them too. Going to have to give it a rest. And start back up next week. Thank you for all your help for I really appreciate it. I will keep you updated. Thank again.

 

[Sea-Girl-in-Paradise]

Hello eveyone. I have good news. She is running and the T&T is working again. I want to thank those whom replied to help me racerone, Crosbyman, and Oldboat1. Thank you. After going through most of the connections, replacing some of the wiring harness, and etc... I went and read some old replies on this forum from 2010 and one stuck out. It said, " Just because it looks good doesn't mean it is good." Well that got me thinking and decided to go and replace the fuse. And bingo. All worked and life is good again. A special thanks to raceron for you were spot on and a special thanks to Crosbyman for directing me and hanging in there. Thanks again, be safe, and happy boating.

 

[Crosbyman]

thanks for the happy feedback...we all learn from it.

p.s. bring a spare fuse or two with you if you are heading out for the big ones