TCI Bad on '03?

[tugla]

split coils maybe......

also when the bike is running either use a temp gauge and see what each header is giving off for heat or spray water and watch closely the evaporation rate.....if your suspect of weak spark.....

if your thinking carbs, is the tank dirty and maybe clogged the carbs....maybe drain the bowls see what comes out.....add another clear fuel filter so you can see any sediment collecting....

just throughing out ideas for ya

 

[infinity999]

Gotcha. I did swap a couple of the coils and that made no difference, at least for cylinder number 3. My big question is, does a TCI just quit working or can it just be weak on a couple of cylinders. Has to be either that or a carb issue, nothing else I can think of that it could be.

Synced the carbs tonight (they were only a little off). Now if I disconnect the plug wire on cylinder 4 it actually makes a difference. Seems to smooth out with the wire disconnected which is odd. Has a bit of stumbling idle with it connected. Maybe bad spark on that cylinder? Both cylinder 3 & 4 are getting some kind of spark because I can see the arc when I disconnect the wires. Mixture screws on cylinder 3 & 4 still do nothing.

 

[infinity999]

Well I am still having issues. I thought I isolated it to a bad coil on cylinder #4 so I ordered a set of COPs from Gannon and installed. Bike is still running on 2 cylinders at idle! At higher rpms I can pull the coils on cylinders 3 & 4 and you can hear the engine stumble. At idle, nothing. I can turn the mixture screws in all the way on cylinders 3 & 4 and nothing! So at higher idle it appears to run on all four cylinders. At idle it is running only on cylinders 1 & 2. If you pull the coils on cylinders 3 & 4 at idle you can make them arc against the block. So they are getting some kind of spark. Maybe not enough? I already tried swapping the coils around to no avail. The are a lot of fumes coming out of the exhaust so I assume carbs 3 & 4 are dumping fuel into the cylinders.

Things that have been done so far:

Replaced coils
Replaced plugs and gapped according to the kit instructions
Tried a different TCI out of Morley's electrical testing kit
Voltage at idle (1k rpm) is approximately 13.35, no real difference in voltage at 2500 rpm
Cabs have been gone through several times
Synced carbs several times

Anyone have any ideas? Been screwing with this bike for months!

 

[Fire-medic]

Well, if Sean has the stuff for lending to replace your electrical components one-by-one, maybe you will find your problem. It's worth a try.

 

[gamorg02]

did you try some OEM coils from morley? i'd try a stock config first.

 

[infinity999]

It did seem ok for a bit with the stock coils. I can't imagine these cops would screw anything up. They are all producing spark. The only thing in the chain I haven't swapped is the MAP sensor. Do these go bad and send erratic signals to the ignition (TCI)? Maybe the spark to cylinders 3 & 4 are out of time because of this? Going to swap it out when I get home...

 

[one2dmax]

Don't forget to check the carb sync if you know it's got spark. The nice thing about an internal combustion engine is that it only needs three things: Compression, Fuel, and Spark and it's going to run. If the sync is off it will idle like crap and should pick up the cylinders when holding the throttle up a little bit.

 

[infinity999]

Checked the carb sync and it's near perfect. Swapped out the Boost (Map Sensor) and no difference. I even took off the airbox and squirted gas down carbs 3 & 4 and it made no difference. Cylinders 3 & 4 are definitely getting spark. I can pull them off and see that spark arcing to the block. Sparks looks very strong, and when it's arcing to the block it can stall the bike out. Probably isn't too difficult since it's only idling on 2 cylinders anyway. Like I said, above idle it seems to be running on all four. So I seem to have fuel, spark and I assume compression. Maybe the cylinders aren't getting the spark at the right time (timing issue)? Maybe an issue with the flywheel? Taking guesses here, not too many other things it could be. The exhaust smells very rich, so I assume carbs 3 & 4 are dumping plenty of fuel into the cylinders.

 

[wildweasel_pt]

Do you know what idle jets you have installed? What about the mixture setting? Are they all similar? You may have too much fuel being dumped into those cylinders

 

[gamorg02]

Checked the carb sync and it's near perfect. Swapped out the Boost (Map Sensor) and no difference. I even took off the airbox and squirted gas down carbs 3 & 4 and it made no difference. Cylinders 3 & 4 are definitely getting spark. I can pull them off and see that spark arcing to the block. Sparks looks very strong, and when it's arcing to the block it can stall the bike out. Probably isn't too difficult since it's only idling on 2 cylinders anyway. Like I said, above idle it seems to be running on all four. So I seem to have fuel, spark and I assume compression. Maybe the cylinders aren't getting the spark at the right time (timing issue)? Maybe an issue with the flywheel? Taking guesses here, not too many other things it could be. The exhaust smells very rich, so I assume carbs 3 & 4 are dumping plenty of fuel into the cylinders.

i doubt timing as i think it'd get worse at higher rpms not resolve itself. also intermittent electrical issues i've found *usually* show at higher rpms too as more is being demanded from the system quicker as well. i'd say something with carbs perhaps.

 

[johnpclynch]

Check your compression I'd say, rule out any internal issues

 

[infinity999]

Well I do have a compression tester, but I doubt I have the right adaptor to screw into the head. The bike has 19k miles on it.

It does seem to run fine while riding. It is definitely not running on 2 cylinders then, that would have to be very noticeable.

The jets in the carbs are all stock and all the same as far as I know. Carbs 3 & 4 have been gone through a few times. Initially I couldn't get the floats set right so I sent them to Dannymax and he set the floats and assured me that they were idling on all four cylinders when he tested them. Also, I am definitely getting spark on all four cylinders (at idle and higher rpms). I did have that same thought last night about 3 & 4 getting too much fuel because the exhaust smells awful. I have all the mixture screws turned 2.5 turns out. Even if I turn the screws all the way in on 3 & 4 it still smells really strong. Why would the mixture screws not work and cause the carbs to still dump large amounts of fuel into those cylinders at idle? That is the question..

One thing that I have also noticed is that the fuel pump runs quite a bit sometimes before starting. Last night I had the engine running, shut it down.. Five minutes later I turned the ignition back on and the pump ran for at least 3-4 seconds. Why would it run that long after the engine had just been running?

 

[dannymax]

Well I do have a compression tester, but I doubt I have the right adaptor to screw into the head. The bike has 19k miles on it.

It does seem to run fine while riding. It is definitely not running on 2 cylinders then, that would have to be very noticeable.

The jets in the carbs are all stock and all the same as far as I know. Carbs 3 & 4 have been gone through a few times. Initially I couldn't get the floats set right so I sent them to Dannymax and he set the floats and assured me that they were idling on all four cylinders when he tested them. Also, I am definitely getting spark on all four cylinders (at idle and higher rpms). I did have that same thought last night about 3 & 4 getting too much fuel because the exhaust smells awful. I have all the mixture screws turned 2.5 turns out. Even if I turn the screws all the way in on 3 & 4 it still smells really strong. Why would the mixture screws not work and cause the carbs to still dump large amounts of fuel into those cylinders at idle? That is the question..

One thing that I have also noticed is that the fuel pump runs quite a bit sometimes before starting. Last night I had the engine running, shut it down.. Five minutes later I turned the ignition back on and the pump ran for at least 3-4 seconds. Why would it run that long after the engine had just been running?

That's odd....I would expect maybe a click or two but 3 or 4 sec. is way to long for that short a shutdown period. Sounds like either it's losing fuel somewhere, (do you see or smell any leaks) or maybe the pressure sensor mechanism on the fuel pump is going haywire.....altho I've never heard of that happening.

 

[dannymax]

I have a set of carbs off my '96 I can send you to test the idle.

 

[gamorg02]

That's odd....I would expect maybe a click or two but 3 or 4 sec. is way to long for that short a shutdown period. Sounds like either it's losing fuel somewhere, (do you see or smell any leaks) or maybe the pressure sensor mechanism on the fuel pump is going haywire.....altho I've never heard of that happening.

IIRC the pressure sensor actually has been documented and i think ninjaneer or yukondave did a writeup on how to rebuild.

but yes much too long

and if danny went through your carbs i'm pretty sure they're good, and almost definitely close enough where it shouldnt' be killing 2 cylinders.

 

[johnpclynch]

That's odd....I would expect maybe a click or two but 3 or 4 sec. is way to long for that short a shutdown period. Sounds like either it's losing fuel somewhere, (do you see or smell any leaks) or maybe the pressure sensor mechanism on the fuel pump is going haywire.....altho I've never heard of that happening.

Does the fuel pump go for 3-4 seconds again if you switch off and back on?

How about something as simple as a crack in the fuel line between the tank and the pump (maybe around the filter) or a clogged filter...
When the fuel pump runs it will suck as much air as fuel (like drinking a milkshake through a straw with a hole in it)... then when fuel does get past the pump its only enough to fill the first two carbs it comes to

 

[dannymax]

IIRC the pressure sensor actually has been documented and i think ninjaneer or yukondave did a writeup on how to rebuild.

but yes much too long

and if danny went through your carbs i'm pretty sure they're good, and almost definitely close enough where it shouldnt' be killing 2 cylinders.

They were cleaned and rebuilt before I got them Garrett....I adjusted the floats, installed them on 'Memax the Mule', set the idle & sync'd them. They sync'd well and bike ran fine.

 

[infinity999]

It's possible there is a crack in the line somewhere, but it seems to run fine above idle. I'll try disconnecting carbs 3 and 4 from the fuel supply and squirt some gas in from the top of the carbs with the engine running and see if there is a response.

 

[dannymax]

Be careful of fire Patrick!

If there is any crack in the lines connecting the carb bodies you should see it by cycling the fuel pump without the motor running.

Or pull the lines off and flex them....they were in good condition I believe, weren't they?

 

[infinity999]

Filter was changed.

If there is a crack in the fuel line wouldn't there be a leak?