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1986 Johnson 150 HP running under load.

S

sns2417

New member
I have an 1986 Johnson VRO 150 hp. When I start it and run it with the earmuff and hose the motor runs sweet. The motor is very responsive all the way up to 5000 rpms. No missing, Idles fine. Then I jump in the truck take it to lake and put it in the water and it doesn't want to run above 1300 RPMS. I have done a compression test and I am at 91 lbs in all cylinders. Anyone have any ideas? I just bought the boat in February. Supposedly the motor has been rebuilt. The oil injection unit has been taken off.

Thanks

Steve
 
Not sure why you would run it at 5000 RPM in nuetral ( no load )------But check to see if you have spark on all 6 cylinders.----In the driveway it will run quite nicely on 3 cylinders.
 
Check compression and spark first, no need to break out the VOM just yet.

You can get an adjustable spark tester at the nearest auto parts store for under 5 bucks.
 
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Alright I went and check the spark and on port side I am getting the blue spark that everyone has talked about in other threads. I gapped the spark tester to 7/16 too. Now on the starboard side I do not have spark. Is there a way to test that CDI box??
 
Check the pins in the connecter plugs for the powerpack.---------------You could always swap the 2 powerpacks to see what happens.
 
Ok I think that I have found my issue. I went and check the connector plugs and found a round blue plug that comes down from fly wheel with 2 brown wires. The blue plug connector is bad. I plug the 2 brown wires in the other end and check spark. I now have spark. My question now is can I buy just the blue rubber insulated connector? Or is it ok to slice and wire direct?

Thank you for everyone that has help me!!!
 
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