Kawasaki Concours Forum

The C10, aka Kawasaki Concours - The Original => The Bike - C10 => Topic started by: bigdt73 on April 01, 2019, 12:07:59 am

Title: No Combustion
Post by: bigdt73 on April 01, 2019, 12:07:59 am
So my project bike is turning into a neverending series of roadblocks. I can't get the bike to start and I'm desperate for any help. Here's hoping someone can help.

I'll try to keep the context as brief but thorough as possible. I'm doing a complete restoration of a 95 C10. I tore the carbs apart and cleaned them to look like new and replaced every rubber piece along with Steve's float bowls. Rebuilt J-box from Larry Buck and an almost new wire harness. Last week I hooked up an auxiliary tank and fired up the bike. It started with the choke but wasn't running very well. I tried adjusting the idle and it would stall out. I could only get it to run for about 15 seconds at a time before it would stall. I then saw gas coming out of Steve's overflow tubes. I drained the carbs and pulled them from the bike. I ordered new float valve needles from Murphs and when they arrived, tore apart the carbs. I replaced all the needles and discovered a bad float. I had a spare set of floats so I put them in. Put it all back together and then the bike wouldn't start at all.

I thought maybe it wasn't getting spark so I pulled all four plugs (brand new NGK plugs). Cylinders 1 and 4 plugs still look brand new like they never fired. Cylinders 2 and 3 plugs had carbon on them. I checked the cylinders and there was no standing gas so the overflow tubes did their job. So maybe the coil is bad? I followed the shop manual for testing the coils and the resistance was within specs for the coils and wires. Then I checked the coil pickup air gaps and they were out of spec. I adjusted them to .5mm, reassembled everything, and still no go. I went back in a readjusted them to .8mm and the same result. Then I used the multimeter and tested the coil pickup and it specs out. I have a spare coil pickup and swapped it with the same result. I also tested the ICU and it specs according to the manual as well.

The battery is brand new and the starter is working good. I hooked up the real tank as well including a Napa filter and a clear fuel line. I can see the fuel is getting to the carbs and I can smell slight gas fumes from the exhaust after trying to start it. But it just won't run.

Thoughts, ideas, suggestions? What am I missing?
Title: Re: No Combustion
Post by: George R. Young on April 01, 2019, 06:42:52 am
With the plugs out and grounded, do you see spark when cranking?

Are you absolutely sure that the pilot jets are clear?
Title: Re: No Combustion
Post by: bigdt73 on April 01, 2019, 09:09:29 am
With the plugs out and grounded, do you see spark when cranking?

Are you absolutely sure that the pilot jets are clear?

Thanks, I'll check on the plugs later today. I'm 99 percent sure that the pilot jets are clear.
Title: Re: No Combustion
Post by: bigdt73 on April 02, 2019, 12:32:56 pm
So there is spark. I can see them firing with the out and grounded. So I guess I need to revisit the carbs...
Title: Re: No Combustion
Post by: MAN OF BLUES on April 02, 2019, 02:36:42 pm
do you positively have the correct spark plug wires, connected to the correct plugs?

sounds silly, but I have seen this many times here.....

L/H COIL TO PLUG #1 & #4
R/H COIL TO PLUG #2 & #3
Title: Re: No Combustion
Post by: bigdt73 on April 02, 2019, 05:03:28 pm
do you positively have the correct spark plug wires, connected to the correct plugs?

sounds silly, but I have seen this many times here.....

L/H COIL TO PLUG #1 & #4
R/H COIL TO PLUG #2 & #3

Nah, it doesn't sound silly. I thought that same thing so I double and triple checked the connections to make sure I had them hooked up correctly. The wires still have the yellow stickers on them so it made it easier to double check the alignment.
Title: Re: No Combustion
Post by: RFH87_Connie on April 03, 2019, 09:08:10 am
Did you set the fuel height correctly in each carb bowl and then bench sync correctly (from reading MOB's article)?  This is very critical.  If they are off, it is probably making it hard to start and may be flooding them enough so it won't fire.  Also, a weak battery that spins the engine can still not be producing enough current to give you a good spark.  A good battery should spin the engine at a nice fast rpm.
Title: Re: No Combustion
Post by: bigdt73 on April 03, 2019, 10:53:26 am
Did you set the fuel height correctly in each carb bowl and then bench sync correctly (from reading MOB's article)?  This is very critical.  If they are off, it is probably making it hard to start and may be flooding them enough so it won't fire.  Also, a weak battery that spins the engine can still not be producing enough current to give you a good spark.  A good battery should spin the engine at a nice fast rpm.

I set the float bowl height to 17mm per the shop manual and visually bench synced the carbs. The battery was purchased from Battery+Bulbs less than a year ago and I have plugged into a battery tender. It spins fast but won't fire.
Title: Re: No Combustion
Post by: gpineau on April 03, 2019, 11:46:15 am
So you checked and you have spark?  In my mind that says either timing or no fuel.

A quick test, is a shot of starter fluid into the air intake while cranking with the throttle wide open. 
If you indeed have spark then it should fire and run for a few seconds.
If it fires then that points to the carbs as the problem.
Title: Re: No Combustion
Post by: connie_rider on April 03, 2019, 01:33:36 pm
gp beat me to it.
Easy way to see if your having carb issues.
But, suggest close throttle while cranking.
  On a CV carb the slides are closed anyway.

Ride safe, Ted

PS: Was the bike running prior to rebuilding the carbs?


Title: Re: No Combustion
Post by: bigdt73 on April 03, 2019, 06:13:46 pm
gp beat me to it.
Easy way to see if your having carb issues.
But, suggest close throttle while cranking.
  On a CV carb the slides are closed anyway.

Ride safe, Ted

PS: Was the bike running prior to rebuilding the carbs?

Ted, I bought the bike as a non-running project bike. Prior to last week, I don't know when it was last running. Last week it ran for a few seconds and not well. I'll have to get some starting fluid to try starting it.
Title: Re: No Combustion
Post by: BobCT on April 04, 2019, 04:43:21 am
How many miles on the bike? Did you check valve clearances? How about air leaking in from torn or not fully seated carb boots?
Tough working on a bought non running bike when you don't know what the po might of done to try and get it to run.
You stated you are using choke(enriched), did you confirm that it is functioning at the carbs when you apply choke?
Title: Re: No Combustion
Post by: bigdt73 on April 04, 2019, 09:29:02 am
How many miles on the bike? Did you check valve clearances? How about air leaking in from torn or not fully seated carb boots?
Tough working on a bought non running bike when you don't know what the po might of done to try and get it to run.
You stated you are using choke(enriched), did you confirm that it is functioning at the carbs when you apply choke?

The bike has approx. 50K miles. I tore the bike down completely (except for a motor tear down), painted the frame, and began a complete reassembly. I did a bent rod test and adjusted the valves to spec. I replaced all the coolant o-rings along with any other rubber parts that were showing age. The carb boots are like new and I double checked that they aren't torn and they are fully seated. The choke seems to be working properly as all the plungers open and close with the choke cable.
Title: Re: No Combustion
Post by: Daytona_Mike on April 05, 2019, 08:00:45 am
Sorry to hear about your issues.  We should eliminate what we can first and start with basics  (I know you checked this but maybe the green and black wires got swapped)
You should see a Green wire which controls coil #2 - those wires go from coil #2 to cylinders 2 and 3
the BK (I assume black) wire runs  coil #1 and those spark plug wires go to cylinders 1 and 4   (spark plugs wires seem ok? no shorting?)
The spark plug gap should be .028 with wire or spark plug gap tool  (not using feeler gauge) They come pre-gapped.. did you open the gap up?

Next lets do a compression test (throttle has to be wide open - all spark plugs out.) and see what we have before we fault the carbs again.
good luck. 
Lets us know so we can advise you further.

 Another test is if you have one of those thermal infra red heat sensor guns  to tell us which of the 4 exhaust pipes are getting hot and which are stone cold. It might help diagnose if you can get it running enough.
Also, you are a smart man to have installed overflow tubes.  You probably already saved the engine from major damage.

One more thing- get rid of that NAPA filter and try the petcock on PRIME please.
 
Have you verified the fuel in the bowls  and test the float valves (drop the hose down lower so more fuel fills the hose and then stops) with a length of clear tubing held next to the carb bowls?  The fuel level should stay right at the split where the bowl meets the carb body.
https://www.youtube.com/watch?v=PHuB1lyagKM (https://www.youtube.com/watch?v=PHuB1lyagKM)

You said this:  I tore the carbs apart and cleaned them to look like new and replaced every rubber piece

  I can assume you did not change the  rubber diaphrams as those are expensive.  Please tell me you did not use carb cleaner?
Do you know how many people have cleaned the carbs to look like new and the engine will not run... a lot~! Are you sure you cleared all the jets/orifices? Assembled them correctly? You 'really really' need to KNOW these carbs to work on them.
Title: Re: No Combustion
Post by: bigdt73 on April 05, 2019, 01:01:25 pm
Daytona_Mike---

All good points, some of which I already checked. I've been following the Kawi shop manual for guidance along with this site (thank you all). I double checked the coil wires and everything is hooked up according to the shop manual and your advice. I cleaned the carb diaphrams with a solution of simple green and there are no tears or holes. I even polished the slides so they are super smooth and shiny. They slide smoothly and easily. Good point about not using carb cleaner. I also gapped the plugs using a wire gauge and most of them were already in spec.

Last week when I first tried starting the bike I was using a Motion Pro auxiliary tank that is either on or off. After it ran horribly and gas came out the overflow tubes, I pulled the carbs and changed the floats and float valves. Upon reassembly I used the bike tank on "prime" and the fuel was flowing freely through the gas line (clear tubing purchased from Murph's). I haven't tried a compression test yet but I believe it's warranted. I will need to get a compression tester.

Today I pulled my carbs again and tore them down, again. I pulled all the jets, the diaphragms, and the needles. I disconnected all the hoses and used carb cleaner and qtips on every surface. Then I used compressed air in every orifice and opening (approx 15-20 psi with a rubber tip). That brings me to a question about the carbs. In the attached picture, what role does the smallest opening play (the small brass orifice at the bottom of the picture)? The one without any removable jets or needle. When I ran compressed air through them, carbs 2 and 3 were fine but carbs 1 and 4 are clogged. No air passes through on 1 and 4 unlike 2 and 3. Is this causing the problem? The manual doesn't spell out their function nor does it specify what they are called.

Title: Re: No Combustion
Post by: RFH87_Connie on April 05, 2019, 01:27:02 pm
Here is a a pic I saved from someone else in the past.  I think the port should be open unless it is related to the pump diaphragm on the carb body's side (I can't remember).  Maybe poking with fishing line a carb cleaner will free it up?
Title: Re: No Combustion
Post by: RFH87_Connie on April 05, 2019, 01:31:09 pm
One more pic that may help for clarity.
Title: Re: No Combustion
Post by: bigdt73 on April 05, 2019, 02:00:21 pm
Here is a a pic I saved from someone else in the past.  I think the port should be open unless it is related to the pump diaphragm on the carb body's side (I can't remember).  Maybe poking with fishing line a carb cleaner will free it up?

I got both of them opened up so all four are clear now. I didn't know their function but I figured they needed to be clear.
Title: Re: No Combustion
Post by: MAN OF BLUES on April 05, 2019, 04:42:54 pm
I got both of them opened up so all four are clear now. I didn't know their function but I figured they needed to be clear.

fuel origin/supply to the starting circuit... controlled by the Pilot Air adjustment needle screw..
did you disassemble and clean all 4 of those? Those are the ones below the pressed in "tamper" plugs...which need to be removed to access that circuit.
there is a screw with a fine tipped "needle", that meters fuel during startup, and up thru the 2500 rpm range, as the throttle plate opens, exposing the 4 holes on the engine side of each carbs "bore", to pull fuel...
if those adjustment screws were never removed, and those circuits "cleaned"... the bike will never "start and run"...
also, if they were removed, they need to be reassembled correctly, with all parts intact, the small rubber o-ring, the backing washer, and the spring, all on the adjustment needle... (items 8 thru 11 in photo) then seated "gently", and backed off 2 full turns from the seat...
Title: Re: No Combustion
Post by: MAN OF BLUES on April 05, 2019, 04:54:52 pm
Pilot air location below...
also, spray gumout (with carbs disassembled) from the rear of the carb, thru both circuits shown in the other photo...along with that circuit you asked about... it should spray out evenly, from all of the small holes in the front bore of the carb "throat".(you will need to cover the pilot airscrew hole with your finger during that process, to allow the other circuits to be pressurized and spray seen...)
Title: Re: No Combustion
Post by: MAN OF BLUES on April 05, 2019, 05:04:18 pm
Here is a a pic I saved from someone else in the past.  I think the port should be open unless it is related to the pump diaphragm on the carb body's side (I can't remember).  Maybe poking with fishing line a carb cleaner will free it up?

what the heck is up wit dat crazy picture?

what bike did that come from, with some crazy electrical connector on a carb????

 :popcorn: :popcorn: :yikes: :yikes:

Title: Re: No Combustion
Post by: MAN OF BLUES on April 05, 2019, 05:32:11 pm
I set the float bowl height to 17mm per the shop manual and visually bench synced the carbs. ......

now, after explaining the pilot air circuit, and it's GREAT importance to starting the bike, and supplying fuel for IDLE, and just above...
HOW did you (explain the method) accomplish your "bench synch"?

When I instruct this process, I direct people to adjust the "idle" knob, to a point where the fixed stop on the carb casting is reached, then, I add 1 turn on the knob, just to "raise it off the positive stop".. then I proceed to adjust the individual carbs, the actual "adjusting screws", to move the throttle plates to a point where each and every carb has the "leading edge" of the throttle plate "covering" 1/2 of the forward hole in the throat... when observed, the "reflection" of the hole, on the throttle plate's bottom edge, should combine with the hole, and make a "perfect circle" in it's reflection, if it's less than that, the bike will not start, (so erring on the heavy side, and if the reflection is actually a "figure 8", it will still start... and backing off later on the knob will bring it back to the correct point) but the "circle" is what you shoot for..and all of the carbs must be equal... and this is all done as I noted before, after installing the pilot airscrews, fully, and backing them off 2 full turns.

if all that is followed, sticking a "synch gage" on the carbs is almost never needed, because they will be soooooo close just sticking the screwdriver on/against the adjusting screw will make it change...
Title: Re: No Combustion
Post by: bigdt73 on April 05, 2019, 06:57:16 pm
fuel origin/supply to the starting circuit... controlled by the Pilot Air adjustment needle screw..
did you disassemble and clean all 4 of those? Those are the ones below the pressed in "tamper" plugs...which need to be removed to access that circuit.
there is a screw with a fine tipped "needle", that meters fuel during startup, and up thru the 2500 rpm range, as the throttle plate opens, exposing the 4 holes on the engine side of each carbs "bore", to pull fuel...
if those adjustment screws were never removed, and those circuits "cleaned"... the bike will never "start and run"...
also, if they were removed, they need to be reassembled correctly, with all parts intact, the small rubber o-ring, the backing washer, and the spring, all on the adjustment needle... (items 8 thru 11 in photo) then seated "gently", and backed off 2 full turns from the seat...

Yes, I removed all the pilot needles and cleaned them thoroughly. There were no plugs in place and they had been previously turned all the way in when I first started working on the bike. After I got the bowls back from Steve I asked him how many turns out and he advised me the same as you. With this most recent dissambly I noticed one of the metal washers was missing. I have spares so I'll make sure to reassemble it per the photo you attached (Thank you!). Right now I'm at AZ bike week so the reassembly won't happen until tomorrow or Sunday. Thank you again, MOB.
Title: Re: No Combustion
Post by: bigdt73 on April 05, 2019, 07:01:06 pm
now, after explaining the pilot air circuit, and it's GREAT importance to starting the bike, and supplying fuel for IDLE, and just above...
HOW did you (explain the method) accomplish your "bench synch"?

When I instruct this process, I direct people to adjust the "idle" knob, to a point where the fixed stop on the carb casting is reached, then, I add 1 turn on the knob, just to "raise it off the positive stop".. then I proceed to adjust the individual carbs, the actual "adjusting screws", to move the throttle plates to a point where each and every carb has the "leading edge" of the throttle plate "covering" 1/2 of the forward hole in the throat... when observed, the "reflection" of the hole, on the throttle plate's bottom edge, should combine with the hole, and make a "perfect circle" in it's reflection, if it's less than that, the bike will not start, (so erring on the heavy side, and if the reflection is actually a "figure 8", it will still start... and backing off later on the knob will bring it back to the correct point) but the "circle" is what you shoot for..and all of the carbs must be equal... and this is all done as I noted before, after installing the pilot airscrews, fully, and backing them off 2 full turns.

if all that is followed, sticking a "synch gage" on the carbs is almost never needed, because they will be soooooo close just sticking the screwdriver on/against the adjusting screw will make it change...

My method was almost the same as you described. I will utilize your method after I reassemble the carbs to be sure it's set the way you described. Thank you.
Title: Re: No Combustion
Post by: bigdt73 on April 08, 2019, 10:45:35 am
Does anybody near Arizona want to buy a project? I did everything MOB suggested about bench synching the carbs after tearing the carbs apart again. I put the carbs back in the bike, hooked up the tank, and put the petcock on "prime". I see the gas flowing through the fuel line and then I see a huge puddle of gas on the floor below the bike coming from the overflow tubes...  :banghead: :banghead: :doh: :doh:

Title: Re: No Combustion
Post by: MAN OF BLUES on April 08, 2019, 03:03:44 pm
when it rains, it pours... float needles...replace, and adjust levels...

start at response #13 here...

http://www.zggtr.org/index.php?topic=24023.msg299987#msg299987 (http://www.zggtr.org/index.php?topic=24023.msg299987#msg299987)

Title: Re: No Combustion
Post by: bigdt73 on April 08, 2019, 05:05:46 pm
when it rains, it pours... float needles...replace, and adjust levels...

start at response #13 here...

[url]http://www.zggtr.org/index.php?topic=24023.msg299987#msg299987[/url] ([url]http://www.zggtr.org/index.php?topic=24023.msg299987#msg299987[/url])


That's the infuriating part--The float needles are brand new. I just purchased them from Murph's week before last.
Title: Re: No Combustion
Post by: jim-d on April 08, 2019, 05:33:18 pm
Ha, I've become a cautionary tale on what not to do to a carburetor.
I feel your pain, believe it!

Left a note for Steve, have not heard back.

Carbs coming back out tonight.
Title: Re: No Combustion
Post by: bigdt73 on April 08, 2019, 05:44:15 pm
Ha, I've become a cautionary tale on what not to do to a carburetor.
I feel your pain, believe it!

Left a note for Steve, have not heard back.

Carbs coming back out tonight.

This will be the fourth time that I'm reinstalling the carbs. I don't like to quit but I'm losing my patience.
Title: Re: No Combustion
Post by: jim-d on April 08, 2019, 06:55:58 pm
Seriously.
What is the hardest part for You?  Took me 3 hours to get those friggin boots back on.  Now I’m worried I’ll rip them and then something else to buy.  But that was definitely the most frustrating part.

Couldn’t find that bar Steve has in the vid and I’m not ready to tourch a good screw driver just yet.

Makes you doubt your sanity.  I know they worked when I bought the bike.

I’m just trying to get it running to sell it and motorcycle frenzy season is not going to last ‘til August.

No pressure!

We need a therapy group thread.
Title: Re: No Combustion
Post by: bigdt73 on April 08, 2019, 07:20:30 pm
Seriously.
What is the hardest part for You?  Took me 3 hours to get those friggin boots back on.  Now I’m worried I’ll rip them and then something else to buy.  But that was definitely the most frustrating part.

Couldn’t find that bar Steve has in the vid and I’m not ready to tourch a good screw driver just yet.

Makes you doubt your sanity.  I know they worked when I bought the bike.

I’m just trying to get it running to sell it and motorcycle frenzy season is not going to last ‘til August.

No pressure!

We need a therapy group thread.

Honestly the hardest part is chasing these gremlins. The first time I pulled the carbs and put them back in, I swore I would never do it again. Now I've got down to a technique that goes fairly smoothly and quickly. The hardest part of it is getting the throttle cable ends in place.
Title: Re: No Combustion
Post by: connie_rider on April 09, 2019, 11:44:08 am
Harbor freight is your buddy (in both cases) here.
They sell a radiator hose installation tool that helps a lot with the boots and long forceps that are useful for doing the cables.
Heating the boots with a hair dryer to soften them helps too.

Ride safe, Ted
Title: Re: No Combustion
Post by: MAN OF BLUES on April 09, 2019, 04:17:28 pm
have all those H/F tools, in multiples, and can say for what its worth, all the "picks/and bendy pointed tools", are well worth it.. but for the carbs, the cheapest screwdriver form dollar general... like the $1 one, heated red hot with a propane torch, and bent at the end 90*, will get ya thru this...

I used to use a "coat hanger" wire/hook" to do this... you don't need to spend big $ on tools...
"invention was the mutha' of necessity...".. be cheap. IT'S a GOOD thing.....