'82 150 Johnny black plugs on port bank only.

[Thompy_04]

'82 150 Johnny has some issues. Planes fine idles great starts great good compression at 95-105 over all 6, new carb kits beginning of the year after a freshen (hone, mic'ed, new rings.). Starboard bank plugs look great slight tan to coffee hue and dry, port is oily black, except for the middle plug which is black but looks new right under the electrode. Suggestions? DVA meter is being assembled by a friend right now so I'll test ignition parts soon. I've lost 8 mph 47 compared to 55 in my 17' Glasstream, imma put her away for the winter and make this my winter project like last year during the freshen. Any suggestions are good suggestions. Oh! I did plug the bypass cover primer holes because I just used my old electric choke and couldn't use the covers I had because they didn't fit from my old '79 150 if that makes any difference. Again this is all 3 cylinders affected on the port bank only.

 

[emdsapmgr]

With the recent carb work, it seems pretty unlikely that all three carbs would not flow fuel on one side of the engine. So, you are probably looking at an ignition problem. That engine has two identical power packs which each control the spark to one head. One head may not be getting any spark. When the engine idles, the plugs will seem wet, oily. That's normal at idle. So, check for spark between the heads. Either the cyl-drop test, or use an inductive timing light to check the quality of spark on each plugwire. Swapping the two power packs may also tell you something-it's easy and there is no cost to it.

 

[racerone]

Thermostat checked ?