Installed New Coil (Running Rough)

LJS30

Member
I took my old coil to Napa where they matched it up with a new one. Well I installed it and now my 861 is running very erratic. I installed new spark plugs, checked connections, but still the same result. What could be the issue?
 
what coil did you have, and what did they give you.

are you 6v or 12v.. are you running any resistors if 12v?

soundguy
 

Soundguy I don't know what's up with my settings but I replied directly to your post yet it replied to my original. Oh well here's the deal.


It's 6volt and according to his books it's internally resisted. My original is a Motorcraft #D4PE-12029-AA. I need to go out back to get the specs on the one they gave me.
 
i forsee problems in your future.,

a 6v round coil on a 6v system needs no resistor.

and I seriously doubt you could find a new coil with an internal resistor.. and if you did it would be a 12v coil.

NOT what you need.

couple that to the fact that I got your reply by accident as you did not reply to my post.. but rather to your original post.

you need a plain and simple 6v round coil. what PART NUMBER coil did the thug at napa push on you...

soundguy
 
6v round don't need a resistor for 6v. PERIOD

the wire diameter and lenght in the primary determins the coils primary resistance.

soundguy
 

You know I really thought taking the old one in would ensure I would receive the right part. I'll take it out and go back.
 
good.. that's their economy line 6v coil.. exactly what you need.. it's not causing your problem...

ic14sb is the economy line 12v coil..

soundguy
 
you got the right one. 6v system needs the ic7 ( 50$ ).. or the ic7sb ( 16$ ).

something else has changed if that caused a problem.

make sure there ar eno hidden resistors in line.

try jumpering out the key switch.

spark look good on all plugs?

choke help any?.

soundguy
 
Was the old coil bad? Is that why you changed it?

What does your spark look like.It should be FAT ADND BLUISH-WHITE, the color of lightning. If it"s not, then there"s a problem most likely in the primary ignition circuit. Make sure the points are not corroded, burned, oily and that they are set correctly. Check the timing and the advance mechanism with a timing light. make sure that you have the correct firing order.Make sure that the small wire from the coil to the disributor is connected to the same terminal with the same sign as the battery ground( i.e. if the battery ground is negative, the small wire to the distributor to the coil should be on the (-) terminal of the coil). Check all the connectionsin the primary circuit for cleanliness and tightness. Jumper across the keys witch to see if that improve the situation. Key switches develope "high resistancitius" and limit primary current.

If you have the requisite spark and the timeing advance and firing order are correct, then chwck you carb adjustments and checkfor fuel delivery to the carb.
Systematically check all these things out and if you find some thing incorrect, fix it and start up and see if it fixed the problem. That way you"ll identify what the problem was and learn something.
 
Look in your cap and see if you see what looks like cracks. I changed the points in my skid steer (4 cyl 172 ford) and it started back firing like crazy. found that a couple of the plugs were actually firing all the time due to carbon tracks. Changed cap and all is good. Good hot spark just may be the culprit.
 

The issue actually started several months ago while I was discing. Basically in order to keep the tractor running smoothly I had to continually keep adding choke. This would occur as I used the tractor for extended periods of time. I made a thread about it and the consensus was that my coil was weak and a new one would solve the issue. Well last week the same issue occurred and the tractor really started running badly so here we are now.
 

adding choke leading to a weak spark diagnosis is the dumbest thang i have read on tractor boards,,, it tells me they don't know chit,,, I will say weak spark can fool the best,,, i can also say the color don't mean chit,,,it can be fat and what ever color your heart desires,,,it still may not lite the fire,,, nuttin wrong with replacing the coil they can fool ya also,,, I can say for damm sure use a spark checker if it will jump the gap on a spark checker move on spark is not your problem,,, yours sounds like a fuel issue...

Sparkchecker001.jpg


invest in a good checker... you will not be bit again...[/img]
 
Interesting, very interesting. Well I'll try to find the thread but if I recall correctly many on here were telling me weak coil thus more choke. I'm going to check the distributor cap like another member mentioned tomorrow and see what the deal is in that sense. I was thinking perhaps a clogged fuel filter perhaps.
 
my choke question was not aimed at spark.. I was asking if choke helped. If it does it can point to a fuel stoppage or vacume leak.

you don't have to be an 'azz' all the time and always assume everyone else in the known univers knows nothing and you know the sum total of all knoledge that the divine has provided.

just because spark is at the root of most of the posts here trying to help this guy diagnose his problem does not mean that is the only thing we are focusing on.

geeze.. no wonder you got banned from the other site...

soundguy
 
if choke helped I'd first guess fuel obstruction or vacume leak before weak spark. spark is easy wnough to check visually.

choke does enrich the mix making the mix fire easier.. thus using choke at startup when spark could be weaker due to battery drain.. but it would be at the very bottom of a longer list of things to check for as a cause / effect relationship to your starting problems IF you do have weak spark.

now.. what was it doing before the coil replacement.

have you jumpered the ignition and ran coil right off battery yet?

soundguy
 

The last time I used it the motor was running very erratic. It was very low on power and sounded almost like it was missing quite a bit. No unusual looking exhaust or anything like that.
I haven't worked on it more today.
 
I dont want to muddy the water here, but that tractor has a history of vapor locking to a degree when it heats up good and hot. The rubber gas line goes too close to the manifold and the cheap gas we got now adds to the problem. If everything else fails, insulate the line a bit and switch to no ethanol gas. If you see any help at all, move the gas line around the front of the engine. the archives has discussion and pictures.
 
(quoted from post at 03:51:20 03/20/11) my choke question was not aimed at spark.. I was asking if choke helped. If it does it can point to a fuel stoppage or vacume leak.

you don't have to be an 'azz' all the time and always assume everyone else in the known univers knows nothing and you know the sum total of all knoledge that the divine has provided.

just because spark is at the root of most of the posts here trying to help this guy diagnose his problem does not mean that is the only thing we are focusing on.

geeze.. no wonder you got banned from the other site...

soundguy

Was not talk'n to you cuzz but you can take it any way you want to...
How many nutz did you have to give up to hang with'em...
I can post anytime I want to but why... I often wonder why you do,,, I wonder why any one wants to play with those girl's... Hang with'em long enuff and they will add your pix to the sheep man pix,,, That's a real family eh",,, everyone their should be proud to be a member...
 

Gonna refine this a little better...

You see this type of suggestion made regular on the net,,, its open ended with no real means of confirming the recommendation... Now being one that gets paid to chase my tail and get beat up when the issue could be confirmed fast and simple... live and learn I have been beat up by weak spark when it should have never happen... Fat are what ever color you like what does that mean,,, we are not their holding the plug wire close to a ground,,, we can not judge the distance, we can not see are hear the snap it throws... With a simple spark checker it will eliminate the systems ability to reach out and knock your socks off... That's information I can see hear and confirm no guess required,, a guess will get you in trouble,,, assuming spark is up to sunff will get you in trouble...

Applying choke could mean your spark is weak :roll: now we are off on a wild goose chase theirs no good diagnostic info in that statement,,, it never hurts to check so install a spark checker,,, spark could be good are bad you could have mutable issues, its a issue you need to eliminate so you can focus on the real problem...

I have not read his whole story I just read he replaced the coil because he had a performance problem that sounded to me like more of a fuel issue that could be diagnosed with out chasing his tail... The archives are full of this baloney that leads folks to chase their tail....
 

only reason I still post over there is to help the casual tractor owner that happens to meander in and really needs help. I don't chit-chat with the admins... they don't particularly like me.

you ought to read some stuff over there.. some things come up are quite funny...

soundguy
 
(quoted from post at 14:15:29 03/21/11)
only reason I still post over there is to help the casual tractor owner that happens to meander in and really needs help. I don't chit-chat with the admins... they don't particularly like me.

you ought to read some stuff over there.. some things come up are quite funny...

soundguy

We sometimes say things we wish we could take back,,, we will get over it and for sure don't need a 3rd party to snap a wip...

I consider you a friend :D
 
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