Recent Topics
Valve issues
by kawie_guy. 09/21/18 01:54 PM
2018 Elantra SE
by wolf_06. 09/21/18 01:36 PM
Nasty looking oil filter
by atikovi. 09/21/18 12:43 PM
Laughing hard.
by StevieC. 09/21/18 12:26 PM
Apologies
by Drew99GT. 09/21/18 12:15 PM
Would Like the Manual Transmission to Make a Comeback?
by Speak2Mountain. 09/21/18 11:39 AM
Leaf Mulcher
by kwijibo. 09/21/18 11:32 AM
Pizza dough too crusty
by zorobabel. 09/21/18 11:26 AM
Lubegard Red or Platinum
by diyjake. 09/21/18 11:01 AM
Storing Car Outside
by Delta. 09/21/18 10:47 AM
Looking at a cheap commuter!
by ryan2022. 09/21/18 09:46 AM
Does Your 3.5EB Make Oil
by Gene K. 09/21/18 09:07 AM
F150 Front Differential
by hatt. 09/21/18 08:45 AM
EU version of Subaru 2.5 FB engine
by IMPALA08. 09/21/18 08:40 AM
New “rules” changing your choice of car?
by daves87rs. 09/21/18 06:04 AM
WIX51334XP Oil Filters
by CB900F2. 09/21/18 05:14 AM
Signal Oil Company radio advertising
by 21Rouge. 09/21/18 04:07 AM
Anyone "Wim Hof"ing ?
by Shannow. 09/21/18 02:35 AM
Newest Members
ScottRousell, Direct_Rejection, donatom, Sylent_Snyper, Ajizzle
66034 Registered Users
Who's Online Now
101 registered members (andyd, 853okg, 2010Civic, 14Accent, Al, 9 invisible), 1,808 guests, and 42 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics290,766
Posts4,849,983
Members66,034
Most Online3,590
Jan 24th, 2017
Donate to BITOG
Previous Thread
Next Thread
Print Thread
Hop To
Spark Plug Interpretation #4674752
02/22/18 08:08 PM
02/22/18 08:08 PM
Joined: Sep 2002
Posts: 2,274
VA
Gebo Online content OP
Gebo  Online Content OP
Joined: Sep 2002
Posts: 2,274
VA
Just took these out of my 1994 Honda Lawn Tractor. Been in for 2 years. What would make one plug run black? Now, I just cranked it up and let it run to get oil warm to change and then removed the plugs after it cooled down.






'98 LEX LS400 280K
'00 LEX GS300 195K
'02 4Runner 225K
'05 Lex LS430 85K
'06 Toyota Highlander 145K
'09 Lex IS350 85K
'07 Lex GX470 58K

Re: Spark Plug Interpretation [Re: Gebo] #4674764
02/22/18 08:24 PM
02/22/18 08:24 PM
Joined: Apr 2009
Posts: 2,933
Canada
boraticus Offline
boraticus  Offline
Joined: Apr 2009
Posts: 2,933
Canada
That little bit of soot built up on the insulator is nothing. It's likely residue from running the machine with the choke on for start up. Had you run the machine under load for a while, chances are it would likely burn off.

What's interesting though is that only one plug has soot on it as though only one cylinder was receiving more fuel?

The sooty plug's electrode appears to be whitish. Which isn't unusual in today's lean running engines.

You have nothing to worry about. The plugs look fine.

The best time to read a spark plug is after running the engine under load for a good period of time. Normally the color should be a tan. But, as I said, today's very lean engines often show very light deposits.

I have a 2005 Craftsman riding mower powered by a Honda GX engine. In the thirteen years that I've owned it, I've yet to pull the spark plugs. Engine starts quickly and runs strong. I've never felt the need to take a look at the plugs. Maybe this year.

Re: Spark Plug Interpretation [Re: Gebo] #4674770
02/22/18 08:29 PM
02/22/18 08:29 PM
Joined: Jun 2003
Posts: 33,074
ME
eljefino Offline
eljefino  Offline
Joined: Jun 2003
Posts: 33,074
ME
When I had a v-twin bike one side was jetted differently from the other on account of cooling.

Re: Spark Plug Interpretation [Re: eljefino] #4674772
02/22/18 08:33 PM
02/22/18 08:33 PM
Joined: Apr 2009
Posts: 2,933
Canada
boraticus Offline
boraticus  Offline
Joined: Apr 2009
Posts: 2,933
Canada
That would make sense with one cylinder behind the other in a vertical installation. Especially in an air cooled engine. But in a horizontal, fan cooled V-twin, I doubt there would be a significant temperature differential between cylinders requiring different jetting and if the engine only has one carb, I'd say we can safely rule that out.

Re: Spark Plug Interpretation [Re: Gebo] #4674806
02/22/18 09:22 PM
02/22/18 09:22 PM
Joined: Dec 2003
Posts: 9,801
Florida, Cape Coral
Eddie Offline
Eddie  Offline
Joined: Dec 2003
Posts: 9,801
Florida, Cape Coral
You should run the tractor at full rpm and mow. Then shut off the gas to kill the engine and pull and check the plugs.


CX5 Touring 2.5L :-)
Re: Spark Plug Interpretation [Re: Gebo] #4674816
02/22/18 09:27 PM
02/22/18 09:27 PM
Joined: Sep 2002
Posts: 2,274
VA
Gebo Online content OP
Gebo  Online Content OP
Joined: Sep 2002
Posts: 2,274
VA
Will do in a few weeks.


'98 LEX LS400 280K
'00 LEX GS300 195K
'02 4Runner 225K
'05 Lex LS430 85K
'06 Toyota Highlander 145K
'09 Lex IS350 85K
'07 Lex GX470 58K

Re: Spark Plug Interpretation [Re: Gebo] #4675038
02/23/18 04:50 AM
02/23/18 04:50 AM
Joined: Jan 2011
Posts: 2,718
N.Ohio
Lubener Offline
Lubener  Offline
Joined: Jan 2011
Posts: 2,718
N.Ohio
You have some oil control issue, compression or weak ignition associated with that one cylinder. That left plug is not acceptable and should look like the other. I have an old craftsman twin that did that, but not as bad, it was a bad magneto coil.


The "thinking" man's friend.
Re: Spark Plug Interpretation [Re: Lubener] #4675406
02/23/18 12:28 PM
02/23/18 12:28 PM
Joined: Apr 2009
Posts: 2,933
Canada
boraticus Offline
boraticus  Offline
Joined: Apr 2009
Posts: 2,933
Canada
Originally Posted By: Lubener
You have some oil control issue, compression or weak ignition associated with that one cylinder. That left plug is not acceptable and should look like the other. I have an old craftsman twin that did that, but not as bad, it was a bad magneto coil.


A little soot doesn't confirm that he has an oil consumption issue. He should just run the machine under load for a while then take a look at the plugs. If the engine isn't smoking blue under load, not likely to be an oil consumption problem.

Re: Spark Plug Interpretation [Re: boraticus] #4676094
02/24/18 05:52 AM
02/24/18 05:52 AM
Joined: Jan 2011
Posts: 2,718
N.Ohio
Lubener Offline
Lubener  Offline
Joined: Jan 2011
Posts: 2,718
N.Ohio
Originally Posted By: boraticus
Originally Posted By: Lubener
You have some oil control issue, compression or weak ignition associated with that one cylinder. That left plug is not acceptable and should look like the other. I have an old craftsman twin that did that, but not as bad, it was a bad magneto coil.


A little soot doesn't confirm that he has an oil consumption issue. He should just run the machine under load for a while then take a look at the plugs. If the engine isn't smoking blue under load, not likely to be an oil consumption problem.

I suggest some oil because of the accumulated craters present. Minor oil consumption may not be bad enough to produce blue smoke.I use the common sense approach, if the plug condition is due to the way it was run,the other cylinder should look poorly as well.I would bet that compression results between the two cylinders are not similiar.

Last edited by Lubener; 02/24/18 05:54 AM.

The "thinking" man's friend.
Re: Spark Plug Interpretation [Re: Lubener] #4676118
02/24/18 07:30 AM
02/24/18 07:30 AM
Joined: Apr 2009
Posts: 2,933
Canada
boraticus Offline
boraticus  Offline
Joined: Apr 2009
Posts: 2,933
Canada
Originally Posted By: Lubener
Originally Posted By: boraticus
Originally Posted By: Lubener
You have some oil control issue, compression or weak ignition associated with that one cylinder. That left plug is not acceptable and should look like the other. I have an old craftsman twin that did that, but not as bad, it was a bad magneto coil.


A little soot doesn't confirm that he has an oil consumption issue. He should just run the machine under load for a while then take a look at the plugs. If the engine isn't smoking blue under load, not likely to be an oil consumption problem.

I suggest some oil because of the accumulated craters present. Minor oil consumption may not be bad enough to produce blue smoke.I use the common sense approach, if the plug condition is due to the way it was run,the other cylinder should look poorly as well.I would bet that compression results between the two cylinders are not similiar.


Possibly could be some compression difference but once heated, would it be of any significance? Maybe the OP could tell us if the engine is consuming oil? If not, I wouldn't be too concerned about it.

Re: Spark Plug Interpretation [Re: Gebo] #4676131
02/24/18 07:56 AM
02/24/18 07:56 AM
Joined: Sep 2002
Posts: 2,274
VA
Gebo Online content OP
Gebo  Online Content OP
Joined: Sep 2002
Posts: 2,274
VA
No oil consumption. Years ago I had a lot of misfiring problems. After talking with local dealer, changing plugs, etc., I ended up replacing both coils thinking it was low voltage. Come to find out I had a much simpler fix that I only figured out on accident. For years I had been washing and replacing the foam filter which covered the expensive paper element filter. The paper looked fine so I kept on using it and just washing and re-oiling the foam filter.

Well, guess what? All my problems were fixed when I replaced the paper filter with a new one. It had gotten clogged with dirt that could not be seen with the naked eye. The clogged paper filter had been restricting air flow causing misfiring. Now I change both air filters every two years along with my gas filter and spark plugs. And only with Honda OEM.

By the way, this is the GXV 620, V Twin, 20 HP Honda engine.


'98 LEX LS400 280K
'00 LEX GS300 195K
'02 4Runner 225K
'05 Lex LS430 85K
'06 Toyota Highlander 145K
'09 Lex IS350 85K
'07 Lex GX470 58K

Re: Spark Plug Interpretation [Re: Gebo] #4676429
02/24/18 01:04 PM
02/24/18 01:04 PM
Joined: Apr 2009
Posts: 2,933
Canada
boraticus Offline
boraticus  Offline
Joined: Apr 2009
Posts: 2,933
Canada
Originally Posted By: Gebo
No oil consumption. Years ago I had a lot of misfiring problems. After talking with local dealer, changing plugs, etc., I ended up replacing both coils thinking it was low voltage. Come to find out I had a much simpler fix that I only figured out on accident. For years I had been washing and replacing the foam filter which covered the expensive paper element filter. The paper looked fine so I kept on using it and just washing and re-oiling the foam filter.

Well, guess what? All my problems were fixed when I replaced the paper filter with a new one. It had gotten clogged with dirt that could not be seen with the naked eye. The clogged paper filter had been restricting air flow causing misfiring. Now I change both air filters every two years along with my gas filter and spark plugs. And only with Honda OEM.

By the way, this is the GXV 620, V Twin, 20 HP Honda engine.


I could be wrong but I don't think you're supposed to oil the foam filter if it's over a paper filter. Doing so would cause the paper filter to become saturated and too restricted if oil gets on it in sufficient quantity.

I've been using the original paper filter on my Honda GXV-530 for going on 13 years. I use compressed air to blow both the foam and paper elements out every so often. It's not very dusty where I cut so, the filter doesn't pull in much dust.

Does your GXV-620 have overead cams? My 530 does, which I thought was unusual. Most GX engines are push rod.

Re: Spark Plug Interpretation [Re: Gebo] #4676461
02/24/18 01:23 PM
02/24/18 01:23 PM
Joined: Sep 2002
Posts: 2,274
VA
Gebo Online content OP
Gebo  Online Content OP
Joined: Sep 2002
Posts: 2,274
VA
boraticus,

You make an excellent point about oiling the foam filter. I know when it is still in the plastic bag there is a little oil in there with the filter. Maybe I was over oiling it. I'll start a new thread on the "oiling the foam."


'98 LEX LS400 280K
'00 LEX GS300 195K
'02 4Runner 225K
'05 Lex LS430 85K
'06 Toyota Highlander 145K
'09 Lex IS350 85K
'07 Lex GX470 58K

Re: Spark Plug Interpretation [Re: Gebo] #4681237
03/01/18 07:23 AM
03/01/18 07:23 AM
Joined: Jan 2011
Posts: 2,718
N.Ohio
Lubener Offline
Lubener  Offline
Joined: Jan 2011
Posts: 2,718
N.Ohio
Originally Posted By: Gebo
boraticus,

You make an excellent point about oiling the foam filter. I know when it is still in the plastic bag there is a little oil in there with the filter. Maybe I was over oiling it. I'll start a new thread on the "oiling the foam."

If that were the case, the other plug would be blackened too. Look elsewhere.


The "thinking" man's friend.

BOB IS THE OIL GUY® Powered by UBB.threads™