70 hp Johnson motor stalling and won't stay running

[Mikecm73]

I have an 84 70hp Johnson motor,stays running and when put into gear it stalls,then won't start and then does and stalls.can someone give some helpful hints.

 

[Mikecm73]

Also it won't run now unless u spray starting ether in carbs.

 

[sphelps]

Mike I,m sure the mods will send this thread over to the J/E repair section .. The guys over there will help you for sure !
Good luck and welcome aboard !

 

[southkogs]

I think I got it moved ... MOD tools are a little funky ...

Welcome aboard Mike. How long will it idle if you don't put it in gear? Is is moving cooling water?

 

[Joe Reeves]

Basic troubleshooting.........................

* - Remove spark plugs.
* - Check compression. What is the compression psi of all individual cylinders?
* - Check spark. Spark should jump a 7/16" gap with a strong blue lightning like flame... a real SNAP! Does it?

********************
(Spark Tester - Home Made)
(J. Reeves)

Most auto part stores have "air gap" spark testers... OR..........

You can use a medium size philips screwdriver (#2 I believe) inserted into the spark plug boot spring connector, then hold the screwdriver shank approximately 7/16" away from the block to check the spark or build the following:

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:

..........X1..........X2

.................X..(grd)

..........X3..........X4

 

[Mikecm73]

Compression is good and spark is strong

 

[Mikecm73]

I ordered a new power pack for motor,just a hunch

 

[ondarvr]

If the power pack was bad spraying starting fluid into the carbs would have no effect.

 

[greasyhands]

I have an 83 70hp that was doing the same thing. My aunt gave me a 1973 Capri Tri-hull with a 1983 Johnson 70hp that sat for a long time. Got it running with the usual, new tank and hose, plugs, battery. Took it to the lake and did exactly what yours sounds like. After reading these forums, took the carbs off and completely went through them, put in new floats and needle valve and seat, cleaned them up really good. Took it back to the lake and it ran 70-80% better, hardly any bogging out. Been running seafoam in every tank, and now it is 100%. I would definitely look at your carbs, and replace the fuel lines to them if they are 1984 vintage still. I would also refrain from starting spray, if anything, use a spray bottle with some premix fuel.

 

[Joe Reeves]

* - Remove spark plugs.
* - Check compression. What is the compression psi of all individual cylinders?
* - Check spark. Spark should jump a 7/16" gap with a strong blue lightning like flame... a real SNAP! Does it?

 

[clemsonfor]

Stop spraying ether in it, there is no oil in that and you may cause the pistons to scratch the cylinders.

But continuing on what ondavar said, spraying a flammable fuel into the carb and it then running would not do anything if powerpack was bad . Sounds like classic bad or plugged carbs on one or 2 or maybe even all 3 cylinders??!!!!

Have you pulled them apart and cleaned them since all this happened? That would be my first thing esp since introducing fuel into the motor causes it to run, that means it's not drawing it's own fuel. And if you cleaned them and then ran it but didn't drain it it is possible to be clogged up again, with the oil hardening into the orfices and the junk fuel now a days.

 

[Mikecm73]

We have a strong spark and all 3 cylinders have good compression at 140psi.carbs are cleaned out and are brand new..just cranks over and that's it.dies anyone know if uts the Reed valves behind carbs or off timing.ocean before then stalled and never started and ran again.starting ether doesn't even get it to run.so I don't know what it is.