HELP!! Cylinder 3 & 5 not firing? :::NEW Final UPDATE 6-9-11::::WOooooHOooooo!!

[fordmano]

I am not having any luck figuring out why I have 2 cylinders NOT firing.

Can half of 2 coils go bad at the same time?
Feels like they fire at higher RPM's has a lean pop but pulls like a scalded ape above 3,500RPM.

Plugs for Cyl. 3 & 5 are sooty black fouled but dry.
Exhaust pipes for Cyl. 3 & 5 are over 140 degrees cooler than Cyl.#1 or 2 or 4 or 6
Idle is almost smooth. Low RPM is rough.
Pull plug wire on 3 or 5 no change in idle sound or rpm.
Pull plug wire on 4 or 6 engine almost dies.
Swapped wire from 3 to 5 both plugged in no idle change.
Swapped plug from 6 to 3 or 5 with plug from 3 now in Cyl. 6 no change.

Definitely not plug related.
Turned Pilot screw in 1/2 turn on Cyl.5 plug still sooty no change in idle sound feel or RPM.

Can one side of two coils go bad at the same time?
Could I have damaged the ICM?

I have not tester compression yet headed out to buy new compression tester the one I have does not fit the threads in the plug holes. Standard old tester for full size plugs. I will pick up a fresh set of plugs also to be 100% sure that is not it.

Does anyone have a Dyna 3000 and the Dyna mini coils sitting around they would like to sell off?

I am feeling it is the ICM, but I am holing I am wrong, can't seem to find a ICM for I/S on eBay right now.

Thanks in advance. I will check back in a couple hours, heard out for plugs and tools.

Oh I originally thought and hoped it was clogged slows again so I ran Techron full bottle in almost full tank and rode for almost 45 minutes 30 at or below 2,500 and the other 15 or so minutes WELL above  3,500RPM. Bike did not get hot but very rough lower RPM's and pulled better than ever from 3,500 up to the rev limiter.

Thanks again.

[giggles]

if your slows are completely plugged that the cleaner cannot get threw them..cleaner isn't going to do much good..only remedy is either replace the slows or clen them manually..i worked on a bike a year ago..manually cleaned the slows..ran great..next day clogged again..this went on for 3 days..till i finally got the crap worked out of them.

[fordmano]

If the slows are clogged, wouldn't that cause lean condition at idle or low RPM's?

Thus the plugs would be more white/grey than Black/sooty?

[gordonv]

Wouldn't black (fouled) plugs mean too much fuel (not burning completely)?

If you have a spark, then fuel should burn. No spark, no burn, no black. Should be wet. (I'm sure someone will correct me if I'm wrong, I am not a mechanic)

You have too much fuel for the engine to burn in the time it's given, that's why they are black.

Are the 2 cylinders that appear to not be firing, on 2 different coils? Then swap the leads from each pair of coils. Will they reach the swap? From the fische, the leads come off the coil, almost looks like the cap can be unscrewed and the lead removed, then you could just swap them at the coil. I tried giving them a little twist when I sold my coils, but they seemed firmly in place. Someone will need to verify this.

If the problem swaps cylinders, then it's a coil issue, if not, then it's something else, carb related I would guess.

[Thunderbolt]

has happened before as mentioned.

[fordmano]

Ok here's where I am now.

Pickedup compression tester it reads a bit low BUT it reads the same on the two problem cylinders as it does on two good cylinders. Cheap harbor freight tester maybe it's bad, borrowed tester probably 40years old same reading just about on all 4 cylinders checked.

Obvious cold exhaust pipes on two cylinders same side of motor.
Pulled bowl from rear right cylinder yep slow is clogged completly. Ah ha I said,,, no farking way I grabed one of the old jets out of parts box completly clean let's try this one in there.... No change at all on that cylinder pull the plug wire while bike is running no change to idle or RPM let it idle for 6-7 minutes motor is getting warm like normal but the two problem cylinders are still under 80degrees at exhaust pipes so I check with two different infrared and one laser temp gauges end of exhaust pipe one side is about 140 degrees an the other is still under 95.

Yes black sooty would be over rich or not burning I am going with the not burning at all.

I defiantly have spark at the plug wire. Ran a screw driver handle up the boot and grounded to engine block it will throw a spark 1"-1.5" nice and blue.
The two bad cylinders are on different coils.

I am still leaning toward bad ICM or bad coils or both. About done for the night getting too dark and cold out to work on the big girl. If I can't figure it out tomorrow then I guess I just start throwing parts at it until I have 2 full bikes in the yard or give in and let a professional fix it and pay the piper lick my wounds and call it a day.

I might just go ahead and order the coils tonight they are not real expensive, and that would always give me spare parts right.

[fordmano]

I also verified the plug gap was correct stock heat range DPR7EA-9

Sure it won't help but I guess the DPR8EA-9 is hotter plug maybe I will help (NOT).

[gordonv]

Correct me if I'm wrong (I'm sure someone will), but I figure that the coil with 2 leads only throws one "spark" down both leads, so you end up with both spark plugs firing at the same time (weither or not each cylinder is at TDC/compression is a different issue).

So if the coil fires a working cylinder, how can you have a bad coil? It would be both or nothing. Since one lead is going to a good firing cylinder, and one lead to a dead cylinder, then there is nothing wrong with the signal to fire (ICM) the coil (1 signal, 2 sparks). It can ONLY be both or nothing, the coil generates the voltage for the spark, and the ICM sends the signal to fire.

[Patrick]

From what you're describing it doesn't sound like an electrical issue.. You say you have fire at the plug wires,but, how about at the sparklers ?. Remove the offending sparklers, attach the wires, make sure the plugs are grounded, crank the engine and watch for spark.. It sounds like you have the classic plugged low jet issue..

[9Ball]

check the diaphragms for these two carbs... might be pinched or small holes...an easy check before removing carb bank again....you can even swap one of the bad firing cylinders with a good one and see if the symptom moves with the needle.

[Ricky-D]

DPR8EA-9 is a colder plug.

***

[fordmano]

Correct me if I'm wrong (I'm sure someone will), but I figure that the coil with 2 leads only throws one "spark" down both leads, so you end up with both spark plugs firing at the same time (weither or not each cylinder is at TDC/compression is a different issue).

So if the coil fires a working cylinder, how can you have a bad coil? It would be both or nothing. Since one lead is going to a good firing cylinder, and one lead to a dead cylinder, then there is nothing wrong with the signal to fire (ICM) the coil (1 signal, 2 sparks). It can ONLY be both or nothing, the coil generates the voltage for the spark, and the ICM sends the signal to fire.

Yes you are correct on the coil fires both wires everytime it fires it's called a wasted spark ignition I think if memory serves. Now I have heard of it but never seen one wire or one coil post/terminal loosing  connection internally but I see a spark from the plug side boot.
What I was thinking is that with the plug out of the cylinder it has no outside pressure and that will reduce the resistance that the air gal provides thus allowing for a spark to much more easily jump the gap across electrodes or over to the grounded engine block. Now if there is a disconnect inside the coil would that cause enough resistance to not be able to create a big enough spark to have the power to jump the gap at the plug when it is inside the pressurized cylinder?

Now is it possible that the ICM is damaged in a way that is causing it to NOT fire on the pulses of the firing order that effects these two dead cylinders?

Another twist sort of, if you reverse the polarity on a coil or two coils can it damage the coil or the coils plug wire or back feed the ICM causing damage to it?

[fordmano]

From what you're describing it doesn't sound like an electrical issue.. You say you have fire at the plug wires,but, how about at the sparklers ?. Remove the offending sparklers, attach the wires, make sure the plugs are grounded, crank the engine and watch for spark.. It sounds like you have the classic plugged low jet issue..

I know it's hard to fathom but I did swap the slow jet out with a stock 35 that was easy to blow through, so if it was a clogged jet itself wouldn't a new clean one fix the problem immediately? And if it was a clogged jet would it still effect the idle somewhat if you pull the plug wife off the plug totally removing spark from effected cylinder? I have NO change in idle feeling or RPM with the effected cylinders plug wire on or off new clean jet or old dirty one. Yes I did pull the plug out and yes I get fire from that spark plug but this is under a low resistance situation there is MUCH more resistance inside the Cylinders atmospher than outside sitting in open air grounded to the block. I even swapped the plug from the good cylinder with the bad cylinders plug no change, old plug from the factory stock set of plugs tried it in either a bad cylinder or a good cylinder in the good cylinder ran as before and in the bad cylinder ran as before with the other plug nonchange to RPM or idle speed or feel.

[fordmano]

check the diaphragms for these two carbs... might be pinched or small holes...an easy check before removing carb bank again....you can even swap one of the bad firing cylinders with a good one and see if the symptom moves with the needle.

Hmm did not think about that, I am a bit weak in the carburetor knowledge area. I will swap the number five and six cylinders diaphragms this morning and see what effect that has. The hole or tear is possible I did clean the diaphragms with a soft microfiber towel and lightly lubed the edges with that dielectric grease, wonder if I got a needle or slider gummed up with that grease? Would gasoline break down or clean out and plugged passageway that had been clogged with that silicone dielectric grease?

If a slider and or needle was sticky wouldn't that more effect rpm increase speed more that actual idle RPM, and would it stick open as much as closed?

[fordmano]

DPR8EA-9 is a colder plug.

***

Thank you Ricky-D for correcting me on that one, I was just not thinking when I read the description in the manual. I got confused in all this panic going on in my little world.

It clearly says (if I would have been thinking) the  #8 is for extended high speed running which you would want a COLDER plug as to not glaze up (from inside cylinder extreme heat) the electrodes and porcelain insulator this creating an poor path for spark creation.

[Earl in Pensacola]

Can you get your hands on (borrow) a known good ICM?  It doesn't matter if from a standard/Tourer or IS, it's just to confirm that the ICM is or is not the problem! If the problem remains, then I personally would try replacing the ignition wires all or just the "problem" cylinders.

[fordmano]

For test purposes would a GoldWing 1500 ICM work?

[gordonv]

If I understand the make up of a coil correctly, if you reversed the wires, then instead of getting 12V in, 50,000v out, you would get 12v in (power source doesn't change) and only 12/50,000v out.

If this is true, then you would not have either cylinder firing on that coil.

Can ANYONE answer the question, are the plug leads removable from the coil, without breaking anything?

fordmano, trying to avoid you removing those carbs agian. Are the 2 leads coming from one of the "bad" coils, can you change the plug they go too? If you can, this will tell you if it is a coil issue or not.

[BonS]

From what you're describing it doesn't sound like an electrical issue.. You say you have fire at the plug wires,but, how about at the sparklers ?. Remove the offending sparklers, attach the wires, make sure the plugs are grounded, crank the engine and watch for spark.. It sounds like you have the classic plugged low jet issue..

I know it's hard to fathom but I did swap the slow jet out with a stock 35 that was easy to blow through, so if it was a clogged jet itself wouldn't a new clean one fix the problem immediately? And if it was a clogged jet would it still effect the idle somewhat if you pull the plug wife off the plug totally removing spark from effected cylinder? I have NO change in idle feeling or RPM with the effected cylinders plug wire on or off new clean jet or old dirty one.

This image shows the slow jet "BIG" radial holes along the side of the jet but there is also the 0.035" small axial hole that must be clear for the jet to work. Blowing isn't a very good test for this as only a hole or two may be open and still not allow gas to flow through the 0.035" hole. If you can see light as you look through the long end then it's probably open enough to get the cylinder running but still may need a fuel cleaner to get it fully open.

[fordmano]

GordonV,

I pulled the rear cool the coil providing spark to cylinders 5 & 6 that is the one the book shows as farthest rear and has the yellow/red + lead I made sure all coils + & - terminals are clean on fully and tight. I swapped the wires for one bad cylinder and one good cylinder at that coil. No change pulled the ICM maxes connection was seated YES pulled it apart made sure connections were all clean then the connector clicked positively tight and solid. Still no change so were now down to 2 possible items.

Least likely the ICM not firing at the proper time for the two effected cylinders or as most are pointing toward the CARBS feeding those two effected cylinders.

I can swap jets without pulling CARBS so I think I will pull the jets out of one good cylinder and swap for jets on one bad cylinder...

If that helps at all then I guess I am ordering new jets again... Probably original factory KEIHN jets instead of Pro-X maybe they are just not accurate at all.

[fordmano]

Oh I did swap the diaphragms and that gave no improvement at all either so down to Jets or internal passage ways or ICM...


Can anyone define clearly how the pulse generator circuit works in it's entirety? What about the ECT engine coolant temp circuit, books says if it is working it will cause a 200rpm change when disconnected.

[fordmano]

What about soaking the stock jets overnight in carb cleaner real stuff not fuel additive type and try again tomorrow after I blow them out and re-install the stock 35's on the 2 bad cylinders?

[fordmano]

BonS,

Actuall I made sure I could see light through all the wholes including the through hole that runs from one end to teh other end,,, the aftermarket 38 would not Cathy any air through it at all.... And the possibly partially blocked stocker 35 should have given some improvement I tell you the RPM does NOT change at all under any condition that I have arranged so far when I pull the plug wire off the effected cylinder if I pull wire from any of the four good cylinder it will almost dies huge change...

[BonS]

Feels like they fire at higher RPM's has a lean pop but pulls like a scalded ape above 3,500RPM.

Exactly what clogged slows feel like. At higher rpm's the main jets and diaphragm/taper needle circuit kicks in.

You are right, if you can move the slows around it should follow the slows if they are the problem.

[fordmano]

Can I please have permission to CUS and swear and kill something.

Well I really F'd up now, I was able to get the jet out of the carb on the bad cylinder earlier and swap it and now I was able to get the bad carb opened up and jet pulled out well the good carb fought me the entire time coming apart and lulling the bowl,,, ok whatever part of my painful learning curve nonbig deal.. Well when I tried to get my 90degree screw driver in there and that was ok but when I twisted/turned it (yes the correct direction) the MOTHER F'in jet broke off and I can't see any way to spin it now other than with vise grip pliers and they sure don't fit under there, pulled to intake runner still no love for me, so the left bank will need to lift up enough to get the carb up high enough to get ahold of it and now that good jet is ruined SOOooooo off I go to order jets figure I will just pay the piper and get all new 38's real KEIHN jets new and clean and while I am waiting I can pull the old ones out and get ready maybe go ahead and pull the entire carb rack again DangNabIt...

Really pissed off at myself with all this... What a crappy way to spend a memorial day instead of BBQing and praising those that have served or are serving and especially those that have given all!!!!!

[fordmano]

Oh my GAWD! I managed to get the jet out before I gave in and pulled the entire carb rack.

Yahoooooooooooooooooo, now I am done for the day.  I will just order a new set of factory KEIHN size 38 slow jets and button this all back up later just worried that the others will clog up while I am waiting.

[John U.]

Matt, when you cleaned the carbs and replaced the slow jets the first time, did you clean the tank? How about a fuel filter? Reclogging jets might indicate dirt or rust in the tank. Just a thought.
Remember to readjust your pilot screws to 1 3/4 out with 38 slows.
Good luck,
John

[giggles]

Matt, when you cleaned the carbs and replaced the slow jets the first time, did you clean the tank? How about a fuel filter? Reclogging jets might indicate dirt or rust in the tank. Just a thought.
Remember to readjust your pilot screws to 1 3/4 out with 38 slows.
Good luck,
John

i would leave them at 1/and 1/2. i too installed 38's this past winter and left the pilots out to 1 and 3/4 where i had them for the 35's..well after installing the 38's. on cold mornings when using the choke the engine was flooding.. turned the pilots back to 1 and 1/2 and everything is fine again.

[John U.]

Not all bikes are the same but many of us who are running 38 slows found that 1 1/2 was too lean.  The setting for 35s is generally 2 1/4. YMMV

[Cyclejohn]

Hey Fordmano. One thing I haven't seen mentioned through your whole ordeal is the pilot screw circuit. Your slow jet can be clear but if the pilot screw circuit is what is blocked then new jets or bigger jets won't help you. If it were me I would remove the pilot screws completely on the affected cylinders, spray carb cleaner in them and let soak, blow through it with air, and then repeat the process 1 or 2 more times. I've fixed several bikes by doing that when all else seemed clear.

[Al in Arkansas]

Fordmano you're scaring me!  I'm about to pull my carbs tomorrow and looking forward to hearing that you've found the problem (though not nearly as interested in resolution as you are!). 
Al

[rh_customs]

 I was going to post with the same problem, but with cyls.1, 3 & 5 not firing, I had already checked out the ignition system, the mechanical, compression and timing and took the jets out and cleaned I thought, but it was the slow speed jets on the right bank the small hole that go the length of the jet. Went to the dealer and picked up 6 - 38 jets at $3.95 @ put them in and back to running on all 6 cyls.

Thanks for all the good information helped me out and good luck with yours.

RH

[fordmano]

Update as of 11:40 am Monday 6-6-11...

Ok first thank all of you that offered suggestions, advice, direction and a little hand holding.

Ok I am waiting on that fancy 90degree carb tool like the one that was talked about recently on another thread. I gave in and shelled out the money last week after banging and cutting my knuckles and fingers up and swearing that I would NOT pull the entire carb rack out again at least not for a while...

I installed the new original Keihin #38 jets from Chaparrel.
I replaced the one in carb#6 that I managed to break off when trying to swap it with the one in question in Carb#5. I also installed a brand new (clean) #38 in carb #5.

Bottom line is it IS clogged jets, I put it all back together and fired it up checking heat rise on the exhaust pipes by hand and then a infrared temp gun. I now will wait until tomorrow when my tool comes in and I can get in there and swap the jet in carb #3.

It is obvious that the jet cured the problem sound is completly different(better) it revs up faster easier less popping when letting off the throttle exhaust sounds better more even and closer to the same temp argue tail pipe.


Thanks all of you, I will be back and let you know tomorrow evening after I get #3 swapped. After this I am considering going ahead and swapping out #1, #2 & #4 with the brand new original name brand Keihin jets.

I guess saving $10 or so just cost me lots of head aches and other physical pain and time cost me way more than the damn $10....
So I officially retract my recomendation of buying Pro-X jets from rockymountainatv.com it may have been low quality of the jets or poorly machined or just my bad luck that they clogged but whatever.

Thanks again,
Matt

[fordmano]

Oh my GAWD!!!!!!!

Those of you who pointed the finger of fail at the jets,,,,,, well your wisdom and experience was exactly correct. Now I never really doubted any of you but I was hoping you were wrong since R&R'in the carb rack seems to be my Kryptonite. Just can't stand pulling those damn fuel suckers.

So after 2 afternoons of fighting with pulling and replacing the slow jets on 3 CARBS all while never pulling anything past the 3 intake runners and the fuel bowls I managed to get these 3 swapped out. Now the question leave the Pro-X jets in place even though thy seem to be of a lessor level of precision than the factory original Keihin jets or kill myself to replace them with the new jets?????

Ok, Ok, I am leaving it alone and just gonna ride her. 

I will check my sync of the CARBS tomorrow and then ride her to work tomorrow night.


Thanks again to all,

Thanks,
Matt

[X Ring]

Matt, you should have just pulled the whole carb bank.  It would have been easier and faster.

Marty

[fordmano]

Yes X-Ring I probably should have but I have had real night mares about the carb rack since I pulled them the first COUPLE of times with so much difficulty and had such a bad running machine after that so I wanted to see if I could avoid pulling the entire thing and just pull the bowls and work from there.

Here is what happens when a lesser expensive off brand jet is used....and you try to replace it with the carbs in place on the bike.

YUCK that's not good! I used the factory stock original Keihin #35 just as a refrerence as to what a NOT jacked up broken one looks like.


Yes I was able to get it all back together and running correctly again.
And to help prove that I really did all of the changes with the carbs still in place on the bike here is a little bit of proof .