1979 70hp Evinrude 3rd cylinder not running

[kitek]

Short History:
I purchased the boat it had a new fuel pump put on it and the owner told me it just got a good bill of health from a shop. I took it out to the lake and it bogged down when trying to open it up. However it would intermit some. I narrowed it down to the # 3 cylinder not running. It had great fire (blue) The carb bowl was EMTPY. Very easy fix of course. I cleaned the carb and replaced the needle and seat. Took the boat back to the lake it ran wonderfully. (Idle kinda rough and tries to die going into gear) I put some Evinrude Fuel system cleaner in the tank to try and prevent # 1 and 2 carb from doing the same thing. At the end of that day it started flaking up again. I went to the lake a week later and it was bogging again. I was already a mile into the lake (I had to get there at steerage since it was a no wake zone) After approx. 30 minutes it opened up and ran great for a half hour. I stopped to drop the top on my boat and it went back to running cruddy again. Within the hour if I did anything but idle it would die. I was towed back in. Here are my current symtoms.

All cylinders are fireing. (bright blue) I removed the screw from the carb bowled. All full of fuel. With the engine running I unplugged each spark plug to look for the cylinder that wasn't hitting. I was back to #3.(bottom) Retested the fire.(blue) Carb has fuel and when spraying fuel directly into the carb, the engine slows instead of speeding up. It appears that the #3 cylinder is burning fuel. If I pull the plug right after running the engine its wet. As if it where flooding?? maybe the float is of but would it not be intermitting? Seems it would always have the problem. Fuel filter is clean and new, bulb gets hard Im not exactly a newb to outboards but Im a little stumped. Any ideas?

Also I hooked a timing light to it to see where it was at and when I pull the trigger on the light it slows the motor WAY down. That isnt right is it? Also how do you hook a tack to this engine?

[tashasdaddy]

check you compression, if over 100, and within 10% of each other, pull and properly clean all the carbs, removing all jets, requires special tool below. remove core plugs, clean. the reassemble with rebuilt kits. pay attention to the carb float adjustment.

[kitek]

check you compression, if over 100, and within 10% of each other, pull and properly clean all the carbs, removing all jets, requires special tool below. remove core plugs, clean. the reassemble with rebuilt kits. pay attention to the carb float adjustment.

Whats the name of that special tool? That way I can purchase them. I have never used them. Besides the compression. I can see how that might play a factor since a stuck ring could break free and let the engine run properly. But would the plug still be wet when its romved? Seems the plug steel would burn the fuel however it just would be much use if the engine. I have a question about the floats. I know the measurements to adjust it. Could it be "more" likely to just be a float flooding the cylinder?

Again do you know how to hook up a tach to this engine? I think its the gray wire on the wiring junction strip right above the power pack?

[HighTrim]

Im not sure of the exact part number of the jet tool, but most (as the ones in the pics) are homemade with a belt sander. Just make it to spec that TD shows in the middle pic. Im also told there is a special colour of Husky that fits perfectly, but am unsure of which exact one, I believe it was TD that mentioned it.

[kitek]

It was the ignition Coil. Even though it had blue spark, it apparently wasn't enough. The motor runs great again.

[jtexas]

after years of reading tashasdad's admonitions about the carb jet tool and doing nothing about it, I finally got around to it - modified a philips head screwdriver with my handy dremel tool and grinder bit. haven't tried it out yet......

[waterwall Ron]

Under a load of pushing a boat, spark needs to be greater than just idling or reving in a fishbowl/testtank, which is why high performance motors need high performance ignitions,especially blown or turbocharged types.

[waterwall Ron]

[QUOTE=waterwall Ron;1491413]Under a load of pushing a boat, spark needs to be greater than just idling or reving in a fishbowl/testtank, which is why high performance motors need high performance ignitions,especially blown or turbocharged types.