Johnson 70EL76D Looper Terminal Block Wiring

[Crosbyman]

tree huggers will change their minds with their electric chain saw as when the big tree flops down on the roof.

lots of info on 2 strokes on the net if one wnats or needs to learn

Welcome to LeeRoy's Ramblings

 

[brodmann]

I'm wondering if you have had some overheat issues and the rings might have gotten compressed and are seized up. Several low-compression issues have been greatly improved on this forum by running some type of additive designed to free up stuck piston rings, but I can't think of the names of any of those additives that were mentioned. I know that "miracle in a bottle" additives promise the world and rarely deliver, but one guy here had about a 20% increase in his compression numbers by using some additives. My dad had a '76 70 HP evinrude that ran forever. It was a great motor and would sometimes sit for 6-8 months without being used when my dad got older and boat rides and fishing trips became rare. He would back it down the ramp in the backyard and it would ALWAYS fire right up. It was pretty amazing. It did eventually get to where it idled great and ran wide open fine, but in between you had to constantly baby it with the choke to keep it running. He eventually gave the motor to me when my 55 HP bit the dust. That was in the early 90's and I think I corrected the problem by replacing the reed valves. It's not a common item to have to replace, but it would decrease compression. You can inspect them by removing the carburetors. Basically just look for any gaps between the "fingers" and the mounting surface.
Good luck to you. Those motors lasted forever with just a little bit of TLC!

 

[Slab Slayer]

An update for all those who replied and gave me incredibly valuable information and guidance regarding my 1976 Johnson 70HP motor issues (Thank You All )...

* This issue was caused purely by human error (that is on me, live and learn) combined with component failure.
* The motor was replaced with a 1976 70HP Evinrude exact match motor with low hours, pristine "like new" condition, all original parts, and phenomenal compression near 120psi on all 3 cyls. The best part of this is that it was purchased in non-running condition for $100 but I did have to drive 4 hours to get it.
* Because I had already equipped the old motor with all new components and could not verify the health of those components on the new motor: Rebuilt Carbs, Fuel Pump, Water Pump, Coils, Spark Plugs, etc., I transplanted all the new parts to the replacement motor. It lit and purred like a kitten on the very first crank, runs like a new motor, and required absolutely no link\sync adjustment. Very happy with that!
* The old motor was damaged by a serious overheat. The Exhaust Manifold plates warped and allowed water intrusion into all three cylinders.
* The overheat was caused by human error in the installation of the Water Pump. The water tube that connects the Water Pump to the Power Head was loose when the lower unit was raised and secured and the tube did not make it into the Water Pump outlet. My failure to verify that it was where it was supposed to be when the lower unit was raised and secured was the human error. But, my lower unit and Exhaust housing was well cooled .
* This error was exacerbated by an old, corroded Alarm Horn in the Control Unit that wouldn't sound. It was also replaced (PIA) with updated internal and external modern digital alarm Sirens that will wake the dead as well as a digital external Head Temp sensor with an alarm.

Even though most of the fishing season was missed, I did set back on the water and put some more fish in the freezer.

Again, thank you all for the help!