Wont Start. Johnson 1979 25hp

[Grudun01]

Need advise. Motor started fine last week, today when trying to start it turns slow like low battery, but battery just came off charger. Both plugs are firing. Turned motor over with plug out and it spun and started. Did this with both plugs. Plugs back in, back to slow turning. Any ideas? 2 weeks ago both cylinders tested fine 118/121

 

[saltchuckmatt]

Probably a weak starter. Easiest way I know is to jump it straight at the starter with some jumper cables. Last hookup is a ground on the motor not the battery.

Otherwise there is a meter diagnosis.

Could be a bad solenoid, wire, etc.

 

[jimmbo]

If the Battery is NFG, being "just off the Charger" means Nothing. However, corroded Connections/Cables/Solenoid can prevent Current getting to the Starter Motor. Some basic Electrical Troubleshooting is Due.

We had the Rope Start version of that engine. Always started in less than 3 pulls.

The Title was "Wont Start". Did you try to start it with a Rope?

 

[cyclops222]

Removing a plug causes it to spin fast enough. Take the battery to a auto parts place to be LOAD TESTED. Post the results of the test. Needed

 

[Grudun01]

If the Battery is NFG, being "just off the Charger" means Nothing. However, corroded Connections/Cables/Solenoid can prevent Current getting to the Starter Motor. Some basic Electrical Troubleshooting is Due.

We had the Rope Start version of that engine. Always started in less than 3 pulls.

The Title was "Wont Start". Did you try to start it with a Rope?

Battery is 3 month old Interstate, replaced all cables and ends when replaced battery. There is no pull start on the motor, it was removed before I acquired it. Replaced solenoid when first got motor. Last week started fine, ran fine. Did notice starter was lightly smoking and had to tap it a couple of times. Guess I'll start with rebuilding starter. It doesn't appear to have been serviced. Thank you for your ideas.

 

[Grudun01]

Removing a plug causes it to spin fast enough. Take the battery to a auto parts place to be LOAD TESTED. Post the results of the test. Needed

Battery is 3 month old Interstate that tested good under load

 

[saltchuckmatt]

Pull the starter apart, easy. Clean it and get the brush kit.

Make a tool out of thin plastic to reinstall or barrow your wife's butter knives.

 

[jimmbo]

There would be some Provision on the Flywheel to hook a Knotted Rope to permit Starting

 

[Grudun01]

There would be some Provision on the Flywheel to hook a Knotted Rope to permit Starting

It spun freely using the rope

 

[Grudun01]

Pull the starter apart, easy. Clean it and get the brush kit.

Make a tool out of thin plastic to reinstall or barrow your wife's butter knives.

Have neighbor rebuilding it now.

 

[Grudun01]

Pull the starter apart, easy. Clean it and get the brush kit.

Make a tool out of thin plastic to reinstall or barrow your wife's butter knives.

Having it rebuilt now. Thank you