Very Black PLug!!!


Well-Known Member
:helpsmilie: :yuk: Just wonderin if anyone can help?
Finally got to run my truck after a little layoff-too damn cold for me!!
Now that the weathers getting nice, i decided to bring er out and have a little fun.
I ran good for about 15 mins...then it stalled twice and after the second time stalling, i couldnt get it started again. So i brought it inside and checked the plug-very very black and wet-to me means im running rich yes?? And that ive probably flooded my engine-sooo should i lean both needles out? or just my high?? Right now the needles are factory settings....25-1 on premium Petro Canada gas....92-93??? I should also note that once or twice during acceleration, it bogged a little.
just wonderin if anyone can :helpsmilie:
If it's idling fine then I don't think there's any reason to adjust the idle needle, the load needle should be the only needle that needs changed.

you are running too rich. get a new plug that one is probaly fouled. get a new plug and return the needles back to factory setting. then make very small adj to the needles a time until its leaned out right.
you are running too rich. get a new plug that one is probaly fouled. get a new plug and return the needles back to factory setting. then make very small adj to the needles a time until its leaned out right.

the last line is IMPORTANT. if on a stock motor with stock exhaust. then 1.5 out on H and 1.25 out on L. when your tuning a Gasser, only turn your needles 1/12th to 1/10th turns MAX....... while adjusting. This is a case of a Little goes a LONG ways.

black and wet are signs or running rich. but how/what you need to adjust will depend on a few things.

i ll find a link to the baja forum with a very good tutorial posted by Doug Johns, aka ESP.
thanks for the tips guys...and if you get that link Timmah!!
I forgot to metnion that im running a FG tuned pipe...will that make much of a dif??? I did some research on the "other" forum...where as to tune to color of a nice camel brown color?
Quick question...if the plug was just black and not wet---ie carbon--what does that mean??
correct on color, carmel brown to medium brown. i cant locate the link
but it goes like this

with a tuned pipe, yes it will make a differance. with a tuned pipe installed start your H needle at 1.75 out or even 2 out. then lean down from there. heres how.

start and bring motor up to running temps, 10 to 15 minutes, without being Hard on it. easy driving but not TOO easy.
once up to temps bring it to you let it idle for about 10 seconds and shut the motor down. pull plug and look at the color. don't adjust nothing YET>

now put plug back in, restart go for a drive. you ll want to do this next step a few times while increasing rpms with each run. this next part is Important to get as true a reading as possible. Run at any given RPM and shut the motor down AS FAST AS YOU CAN after you run it ten or so seconds. by letting the motor continue to run at a different rpm while performing this tuneing. you could get a wrong plug color and throw you off a bit. Run it for 10 seconds steady at a given rpm, Kill it ASAP, pull plug and look at color. this will give you the most accurate color readings of the plug.

all your doing in this first part is makeing sure your not too lean as you move up the rpm scale to wot.
now, do a low speed run for about 10 seconds, and shut it down pull plug check color. restart do a faster rpm run, bring back shut down asap, pull plug check color, do this a few time until your up to wot, and you don't see a color thats tan or light tan, if you do at any rpm richen the needle most affecting the rpm, ie. low rpm, low needle mid rpm low/high needle high rpm high needle ect..

once you ran it up to wot and are comfy the needles are ok.
now start to retune for performance

start the above process over, but this time you ll look at the plug and adjust the corrisponding needle.

do a low speed run check plug, adjust the needle by no more than 1/10 turns at a time ( i do 1/12ths or 1/18ths usually) and check plug color, Dark is Rich, Light is lean, again your shooting for a Carmel Brown. so, if its dark lean it a touch, redo the rmp run, and recheck color. once your around carmel brown, move up the rpm scale and start the process over at this scale. by the time your doing your wot runs. you should be running a decent carmel , color thur Most of the rpm range. at some rpms, the color may be a bit darker or lighter then the rpm range next to it. as long as your not getting light carmel/ tannish in color your ok.

remember these needles are VERY senstive unlike nitros.

when you get it all done you ll be good to go. once you do it a few times it faster, and after your comfy and know the tune is good, you can with time, learn to tune by the way the motor is running.
It CAN also be a clogged Air filter.
They Do tend to get dirty.... and sometimes they get dirty quick.
Or a Choke that somehow got knocked back to the ON position
Good Points Rex. Often we look past the obvious checks for the lesser likely issue. hopefully most will of checked these common points of issue, but its always good to thow it at the wall, and see if something sticks.
:) cleaned the filter previousl to aking it out but yeah, i always check my choke and such before heading out.
Got myself a new plug and was out today..reset needles to factory setting and went from there. 25:1, fg tuned pipe(chrome), premium gas....
soooo....i start it up..idles nice and fine (to me anyway;) ) a couple mid throttle runs....trying to be steady on the rpms....stop pull adjustment to hogh needle....couple runs mid rpm...stop pull adjusmtent again...couple runs....bogs on acceleration at mid rpm, which indicates a lean high needle???
Readjust needle..truck accelerates fine but the plug is still bark (ie black). would the low needle have any bearing on this at all??? Is it ok to run with a black plug or is it still running a tad rich? I did notice however that each time i pulled the plug it WASNT wet....and then i got frustrated and just ran the rest of my tank out up and down my street!!!:):):) And talk to the hundred people who wanted to know what it was!!!;)
Im out again some looking ot be nice weather!!! So ill continue playin with my needles then and see what i can get.
But thanks to all who replied and have helped...much appreciated!!
thats what i wasa gonna try next...just finished off my batch of 25:1, gonna do 32:1 next...the oil im using is the fg stuff.....dark brown in colour, made it free when i bought my truck...dunno if you have seen the oil they sell at Advanced...but this is it..
As for plug gap...did the old business card trick;)
So, ill see how it goes tomorrow....
Get Quality Oil. AmsOil, Klots, BelRay or the like, don't buy the cheapy stuff from the local hardware store. get some quality 100% synthetic oil.

Yes your low needle can/will affect the motor at lower RPMS.
the Low needle takes the motor form Idle to somewhere near the middle of the rpm range, and then the high needle takes over. if you were doing MID speed passes, then a good portion of the fuel going thru the motor was likely coming form the low needle...

reset your H needle to 1.5 out and start working up the rpm range from idle and check the plug color after each run. if you get to mid rpm runs and the plug is still really black, then lean up the l needle just a touch. no more the 1/12th turns and try again. you ll see the plug getting lighter in color as you lean up the low needle. go to medium dark brown for now then move up the rpm range and adjust the H needle. when you have the H needle adjusted well, turn back to the l needle and recheck the idle to mid rpms and adjust for a medium brown, or nice carmel color.
remember these few things and you should be good before to long

When checking plug colors, the most important aspect is to get the motor turned off ASAP form the defined RPM Run. the longer the motor runs at a different rpm than what you are trying to tune for, the more the plug color will be wrong. kill the motor ASAP. personally i tie the car/truck down to a cinder block or something so it don't move, just spins. for offroad i do it in the dirt. for on road i use very very smooth concrete pad or blacktop and keep a good bottle of water to allow the tires to spin without eating all the tread away.

Only tune a warmed up motor

a little turn goes A LONG WAYs when it comes to both H and L needle adjustments on gassers. it only takes a quick pass by with the needles set to lean to lean sieze these small motors.

Check the color at varried rpms while going from Idle to WOT. and then start your actual tuning on the WOT Runs, and when its done do the low end and finially set the idle speed.

is always good to check the plug condition before and after your running to see nothing has changed too much, ie, temps, fuel ratio, humidity ect.
Expect to need to retune with motor upgrades. new/different exhausts, different air filter, different pistons/cylinders/ and even just a new pison ring warrent retuning the motor.
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Hey ever get tired or writing sometimes???;););) :):)
Anyway just an udate..i must be getting closer....plug is not black but a very very dark brown....i am now running at 32:1 ratio....must be doin something right?!?
Timmah...thanks for all the info...been a great help!!!
Its been too long, Help me remember....

Guy's when staring over from scratch where do you set the idle screw before changing the L screw. When I changed the pipe on my Firehammer it really got screwed up. At factory settings I had to crank the idle all the way up just to get it to half arse idle and now that I got the L leaned a little I don't know where to back the idle down to? Man its been a long time since I needed to tune these things, you forget.:blush:

This is how my mind sees my problem: take off your idle screw and setting your H&L back to factory, where would you or how many turns in on the idle screw would you start?:(

I just screwed mine in until it touch, then one more full turn... I may be and probably wrong because I just used my ears for what I think the ideal idle RPM is, but it seems ok for me ATM.
I'm just waiting for my engine to toast so I can have an excuse to install the upgrade...:clown:
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