72 Johnson 100hp Controls

[mav6759]

Quick question, I have lost spark to my motor. As I looked at the controls I don't see a kill switch now where on the controls. Does anyone know if there is an internal kill switch in the controls that may stop the motor from firing. I'm assuming that the controls are the same year as the motor.

Mav6759

 

[jay_merrill]

Re: 72 Johnson 100hp Controls

The 1972 Hydroelectric control box doesn't have a kill switch. What is common, however, is for the key switch to have an internal problem affecting the "on position."

I would do the "key switch check" to see if that is your problem. I don't have a service manual for your motor (mine is a 1972 65hp), so I can't give you exact information on this. Basically what you need to do, however, is to disconnect one of the key switch wires and then check for spark on each cylinder, while cranking the motor. On my motor, this is done by disconnecting a black/yellow wire at the #6 terminal on the powerpack, but your motor isn't set up the same way.

Perhaps some of the others here, who have complete info on the 1972 100 hp motor, can give you more exact instructions.

 

[al27023]

Re: 72 Johnson 100hp Controls

I no longer have any manuals on this but the power pack is called a battery CD system requiring a heavy battery draw and the battery has to be in good condition for it to run. Killing the battery will result in killing the power pack in many cases.
Get a manual that applies to 72 J/E 100 engine - checks are not real difficult and a replacement power pack is expensive but an aftermarket unit is available - if required to replace, all manufacturer's require replacing coil also.
Be sure to start troubleshooting with a high amp capacity battery installed, even if you have to borrow one and be sure it is fully charged.
Good luck.

 

[mav6759]

Re: 72 Johnson 100hp Controls

Thanks for the replies, But I have another question. I have two wires coming out of controls, one is gray and the other is black, I went to order the book, but when it arrived, I order the wrong book, I got the book for the 72 65hp as you meationed in the last thread. Do anyone know were these wires go. Do they have anything to do with the fireing from the power pack. Also, I'm going to replace the key cylinder, it a small price, I found one for 10.00 so it would be easy just to replace the cylinder.

Mav6759

 

[jay_merrill]

Re: 72 Johnson 100hp Controls

The gray wire comes from the rectifier and connects to an rpm guage. On the switch - is this a new one and is it the one specified for your motor/controls?

 

[mav6759]

Re: 72 Johnson 100hp Controls

I'm not sure, all i know is I have two wires i have know idea where they go. But the problem I'm having is that the whole motor is not firing, would anything in the control such as these two wires stop the motor as a whole from firing, and if you could tell me how these wires are connected. I am waiting on the correct book for this motor.