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1987 15 hp Johnson (J15CUD) powerpack and spark plugs questions...

1987 15 hp Johnson just came back from the shop for an ignition problem that I could not successfully resolve myself. Haven't even run it yet, but I know that it went into the shop with two (new) QL77JC4 plugs and came back with two (new) QL82YC plugs. I cannot find QL82YC plugs spec'd for any OMC 2-40 hp between 1973 -- 1990.
Does anyone know if there is any noteworthy heat range (or any other significant or noteworthy) difference between these two (Champion) plugs?

Power pack was apparently the problem and it was replaced after the stator tested out ok. Is there any difference between power pack 586800 (the OEM spec for this motor, in place before the shop visit) and the new 586799 powerpack that was installed by the shop?

I'm not savvy enough to know the difference (if any) between the old vs. new plugs and old vs. new powerpack part numbers. I do know that the motor went into the shop with OEM spec'd plugs and OEM spec'd powerpack, but came back with different (not OEM spec'd) part numbers.

Any knowledgeable, informed input, warnings or reassurances would be welcomed and sincerely appreciated.
I'm not going to put this motor back on the boat until I run these questions to ground. Thanks in advance for any help.
 
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Call the shop and they will explain to you.

That's the obvious move and one which I already attempted, but that small shop is closed for a few days due to a death in the family over the weekend.
I have a few (very rare for me) days off starting today when I can use the boat, so I was hoping for more than that obvious suggestion.
 
On MARINE ENGINE.COM the 586799 is not recognized.-----Run the motor as it will run just fine.

Yes, I was aware that 586799 is not recognized on MarineEngine.com before I even posted my inquiry, but that number is clear and legible on the brand new powerpack.

I realize that they test ran the motor after installing the new powerpack; I am actually more concerned about the new spark plugs, whose number I cannot find listed anywhere as applicable on any 1973-1990 OMC motor of any size between 2-40 hp, inclusive. :confused:
 
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1987 15 hp Johnson just came back from the shop for an ignition problem that I could not successfully resolve myself. Haven't even run it yet, but I know that it went into the shop with two (new) QL77JC4 plugs and came back with two (new) QL82YC plugs. I cannot find QL82YC plugs spec'd for any OMC 2-40 hp between 1973 -- 1990.
Does anyone know if there is any noteworthy heat range (or any other significant or noteworthy) difference between these two (Champion) plugs?

Power pack was apparently the problem and it was replaced after the stator tested out ok. Is there any difference between power pack 586800 (the OEM spec for this motor, in place before the shop visit) and the new 586799 powerpack that was installed by the shop?

I'm not savvy enough to know the difference (if any) between the old vs. new plugs and old vs. new powerpack part numbers. I do know that the motor went into the shop with OEM spec'd plugs and OEM spec'd powerpack, but came back with different (not OEM spec'd) part numbers.

Any knowledgeable, informed input, warnings or reassurances would be welcomed and sincerely appreciated.
I'm not going to put this motor back on the boat until I run these questions to ground. Thanks in advance for any help.
One has a very slightly higher heat rating than the other ( 82 against 77)
J in the code indicates a cut back ground electrode. Y indicates a projected core nose
 
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