calboats
Seaman Apprentice
- Joined
- Jun 6, 2009
- Messages
- 41
As a brief background, I have a 1987 Evinrude 48 ESLCUS (originally) -- the (clod!) rebuilder I got it from put on different carbs (top) # 318505-D2 and (bottom) #318505-D4 and they have fully adjustable needles. The water pump was bad as purchased, overheated, so I got to have the head shaved, not sure but .040 comes to mind, anyhow it got fixed right, finally. I decided to remove the thermostat, on advice from a different repair guy, so it isn't going to overheat again. Had a Pro tune up "in the water", by an auto repair website owner. Runs cooler, so I'm Just careful to let it warm up a lot before heading out.
Knowing I would have to determine the plugs "new" correct heat range due to all the changes, I started with Champion L77JC4 gapped to .040 as recommended. They came out dark grey, not bad oily, but damp, and pretty sooty overall, two sets used. I was offered a different set, NGK B7 HS 10 plugs, and gapped them at .040 as well. Last week end I swapped plugs at the lake, and wow! -- no more carbon oily soot & black insulators -- carmel colored insulators now at two hours use, with just a trace of black on the electrode, and runs better, faster by GPS tach. Turn key starter, momentary choke, after overnight camp.
Now the Questions??
With all the "stuff" that has changed on the motor, is it still safe to go by what the actual plug color looks like after a couple hours of running, say a 4K average cruise?? If it works and looks good, is it ok to use a different plug range, or brand of plug, if that corrects non standard changes?? What the heck carbs are these anyhow ?? Any guesses as to what the HP might be now, just curious.
Does idiling for a couple minutes change the plug color much?? I pulled back in, and let the gas idle out of the carbs, gas line disconnected, checked plugs at home. Maybe I am seeing idle plug color, but can only a few minutes change it that much??
Sometimes I'd like to damage the "pro" I got it from, but now the motor runs great, after a bunch of extra work and money, but it sure isn't his fault it survived so well. That is due mostly to iBoat guys.
Thanks for any thoughts on my "composite" motor ---- Cal
PS -- I'm still super pleased with electric fuel pump (in line) as an addition to diaphragm pump for priming ONLY. Quick, quiet, easy tank changes, and no more bulbs to squeeze.
Knowing I would have to determine the plugs "new" correct heat range due to all the changes, I started with Champion L77JC4 gapped to .040 as recommended. They came out dark grey, not bad oily, but damp, and pretty sooty overall, two sets used. I was offered a different set, NGK B7 HS 10 plugs, and gapped them at .040 as well. Last week end I swapped plugs at the lake, and wow! -- no more carbon oily soot & black insulators -- carmel colored insulators now at two hours use, with just a trace of black on the electrode, and runs better, faster by GPS tach. Turn key starter, momentary choke, after overnight camp.
Now the Questions??
With all the "stuff" that has changed on the motor, is it still safe to go by what the actual plug color looks like after a couple hours of running, say a 4K average cruise?? If it works and looks good, is it ok to use a different plug range, or brand of plug, if that corrects non standard changes?? What the heck carbs are these anyhow ?? Any guesses as to what the HP might be now, just curious.
Does idiling for a couple minutes change the plug color much?? I pulled back in, and let the gas idle out of the carbs, gas line disconnected, checked plugs at home. Maybe I am seeing idle plug color, but can only a few minutes change it that much??
Sometimes I'd like to damage the "pro" I got it from, but now the motor runs great, after a bunch of extra work and money, but it sure isn't his fault it survived so well. That is due mostly to iBoat guys.
Thanks for any thoughts on my "composite" motor ---- Cal
PS -- I'm still super pleased with electric fuel pump (in line) as an addition to diaphragm pump for priming ONLY. Quick, quiet, easy tank changes, and no more bulbs to squeeze.
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