1976 johnson 15e76a

[edgates]

recently bought a 76 johnson 15 hp put in new plugs, points condensers, rebuilt card, new coils, new water pump, crankshaft key and cam. After fixing everything I could find and doing some for just for heck of it. When I get the motor started it stall easily after warm up and when i try to restart it, I get kickback on compression stroke, ( I am assuming compression) Compression is 105 both cylinders cold and about 100 after warm up. I have checked to make sure my coils, points etc. are wired correctly. Did I buy an repairable motor i.e . bad crank or somthing?

 

[racerone]

Did you torque the flywheel nut ?

 

[909]

I recently rebuilt the exact same motor a 2 weeks ago.

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Try gently seating the low idle needle, then backing out 1.5 turns. I removed the top half of the air intake to access it.

I hope you used an OEM kit to rebuild the carb, and replaced almost everything.

 

[edgates]

Did you torque the flywheel nut ?

Yes don't remember exact spec tho...

 

[edgates]

I recently rebuilt the exact same motor a 2 weeks ago.

Watch q2u0p5 | Streamable

Watch this video on Streamable.

streamable.com

Try gently seating the low idle needle, then backing out 1.5 turns. I removed the top half of the air intake to access it.

I hope you used an OEM kit to rebuild the carb, and replaced almost everything.

Yes paid a hefty price for an nos oem kit. I think I may have failed to line up timing marks on flywheel to roller cam. That came to me in the middle of the night.

 

[oldboat1]

Did you use an oem flywheel key, or one from the hardware store?

 

[racerone]

The ones from the hardware store " look " to be the same.-----But on many models they are NOT the same.

 

[edgates]

Did you use an oem flywheel key, or one from the hardware store?

yes got it off ebay, seller listed as nos oem

 

[edgates]

The ones from the hardware store " look " to be the same.-----But on many models they are NOT the same.

I am however replacing crankshaft key again, broke the original, broke the new replacement, and broke one I took off parts motor. Also broke original cam lobe on crank and the original. About to give up and put this motor away somewhere. go buy one that actually runs.

 

[racerone]

The factory flywheel key locates the flywheel for proper ignition spark and timing.-----The flywheel is driven by the locking tapers.------Tapers can be lapped together for proper fit.------Assemble clean and dry.----Torque the nut.

 

[edgates]

I assume you set the key in place and slide the cam lobe over it. any suggestion on how to make it any easier that using oversized socket on cam and gently tapping it down? and would you put all the down on crank on top of seal? any input is appreciated.

 

[edgates]

Turns out key was setting in crank properly as to catch the flywheel completely and allowing it slip just a hair bit throwing off timing. reset the key and now runs like a scalded dog. thanks for advice.