1962 Johnson 75HP V4SL-14B not getting spark

[62Larson]

This motor is new to me and the previous owner said when he got it the breaker points were bad so he changed them and he got the motor running but it needed fine-tuning. I however, have not been able to get it running. It turns over just fine, it's getting gas, but I'm not getting any spark. It's got new plugs, just checked the gap and they're fine, new rotor, cap, condenser, points and magneto shaft. I just got done taking the coil out and driving it to a shop to have it tested and it tests fine. Put the coil back in and redid the breaker points just to make sure but still nothing. If anyone has any suggestions they would be greatly appreciated. This is my first boat and it's proving to be quite the head scratcher.

 

[oldboat1]

See if you have continuity in the plug wires, boot to boot.

 

[boobie]

Make sure there is no oil film on the breaker points.

 

[Chris1956]

Did you test for spark at the brass button on the coil? If no spark work backwards into magneto, and then to points and condenser.

The coil wire that exits distributor body cannot be grounded. Disconnect the ignition killer wire from it Make sure the connection to the point wire is clean and tight. Make sure the wire between the two sets of points, under the pulley cover is not shorting to the pulley and not broken. (This is very likely your problem)

The other side of the coil must be grounded to the distributor body..

Set both sets of points to a max opening of .020 inches.

Those magnetos work real well. Just Spin the distributor pulley and it will zap you with a good spark.

 

[62Larson]

Thanks everyone, I did everything you've asked about with the exception of testing for spark at the brass button, I'll do that next. Checked the compression as well, just to make sure I wasn't dealing with a bigger issue and they all tested at 62, which isn't great, but it has been sitting for a VERY long time.

 

[Chris1956]

As long as the compression is the same across all cylinders, the motor should run fine. Those were never high compression motors, although 62PSI makes me think your gauge is inaccurate.