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Discolored plug out of 6 plugs J225hp 87

M

mokaction

Regular Contributor
"Thanks in advance for the adv

"Thanks in advance for the advice.

I was checking out my plugs today, and notice that one of them was discolored compared to the others which all looked normal? Also check compressions and they were all 95psi for a looper.

What can cause this discolored plug?

1. Fuel to lean or to much?
2. Bad spark?

Also what carb goes to what cylinder? Is it like a crossflow, where the carb is across from the cylinder? Or is number 1 cylinder on the port side have the port side carb?

Larry
40148.jpg
"
 
"Larry

#1 is highest bank,

"Larry

#1 is highest bank, usually starboard
u have six carbs
the carbs go 1,3,5 starboard
2,4,6 port"
 
"Justintime,

I know which c

"Justintime,

I know which cyl is which. Is just starboard cyl 1 is starboard carb 1?? right?? Also as for the plug, what do you think is causing that discoloring?

Larry"
 
"Normal Condition
An engine&#

"Normal Condition
An engine's condition can be judged by the appearance of the spark plug's firing end. If the firing end of a spark plug is brown or light gray, the condition can be judged to be good and the spark plug is functioning optimally

Dry and Wet Fouling
Although there are many different cases, if the insulation resistance between the center electrode and the shell is over 10 ohms, the engine can be started normally. If the insulation resistance drops to 0 ohms, the firing end is fouled by either wet or dry carbon."
 
larry u can test if fouled
pu

larry u can test if fouled
put the plugs back in
take it for a spin
now shut it down
get your ohm meter
go from spark plug end with read laed
go to engine block with balck
u should read OL/open
if u read 0000 or something u r fouled
 
well u did the coil primary te

well u did the coil primary test right?
what were the readings

what were the coil seconday readings?
 
"The colour of the plug does n

"The colour of the plug does not look too bad, would have been better I I could see all, but it looks 'wet'. That may indicate a carburator/fuel problem."
 
"Larry.... Look directly at th

"Larry.... Look directly at the carburetors. Notice the highest carburetor = #1 cylinder. Next highest carburetor = #2 etc etc.

The carburetors criss cross, that is the carburetors as you're facing them.... carbs on your left arm side feed the oposite side cylinders.

Check the coil on that related spark plug cylinder for continuity. There should be a ohm reading between the spark plug boot and the coil ground, and also between the spark plug boot and the primary lead of the coil."
 
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