Engine doesn't start anymore....

After taking my carbs apart, re-building it with a new carb kit, giving it the berryman's treatment and putting it all back together, I finally put it all back on the bike. It came to life immediately and I was all happy. I was able to get it adjust idle but in the process it felt like I drained the battery (since I was turning off the engine a lot).

But now it doesn't want to start anymore. I checked the spark plugs and the sparks look good. The engine itself is turning just fine. But it doesn't want to fire up. I'm concerned about at least one of the carbs being flooded though I thought I set the fuel level correctly. I'm re-charging the battery and I'm going to wait till it's back to full charge before trying to start it up again. Otherwise, I'll pull the carbs out (for the n'th time) to re-check fuel level.

What else should I be looking for? This has never happened before and this bike always started well just before it was having problems revving on load which resulted in me pulling out the carbs for complete cleaning since I had not done it before.

I pulled out the spark plugs again and they seemed to be a little wet. Could this just be the engine being flooded? I opened the throttle fully while trying to crank it and that didn't help. I've also confirmed that one of the carbs (for cylinder 1) is set to too high of a fuel level. I need to pull the carbs out for sure.

fuse blown?

Getting enough volts to the coils....charge battery?

Kill switch on or off....hey I did it once...when I found it on and switched to start....kaboom from the gas in the cyclinder / header....scared the chit out of me..... :blink: :blink: :woohoo:

Sounds like your hunch about weak battery could be it. Give it a full charge, let the flood clear and try again.

I don't touch the gas when starting my KZ750 unless I'm kicking it. Then I blip the throttle twice before kicking. Not sure that actually has any effect, but it's what I do

you may want to check the float levels

OK. I'm stumped. I spent a lot of time with the carbs and set the fluid levels correctly and put the carbs back on the vehicle. The bike refuses to start and acts like it's not getting any fire. Here are my findings and hope an expert here can help:

- Compression good on all four cylinders (>150 psi)
- Good spark on all 4 spark plugs
- Spraying starter fluid does not help any bit. :ohmy:
- Trying to "air" the system by turning the throttle a bit during ignition does not seem to help.
- Motor is turning well ( I opened the case where the advancer is and saw the rod turn)
- Fuel is passing through all jets fine including pilot. I just installed new rebuild set (yes, I set the main jet needle at the right setting though this shouldn't matter for startup?). These are TK-22 carbs.

The fact that even the start fuild isn't helping suggests that this is not a fuel issue but more a fire issue but the sparks look good so I'm stumped. This is the first time it's started to do this. It always started once I had the choke on; I had it on this time too. I really really need help. Patton, Lou, where are you guys?

Where there's compression and fuel and spark, the spark may be occurring at the wrong time, which might be caused by incorrect routing of the plug wires from the coils.

Would first double-check to assure that plug wires from the left-side coil with the small green wire are connected to the inside plugs.
And that the plug wires from the right-side coil with the small black wire are connected to the outside plugs.



Good Fortune!

Thanks Patton. I'll check the wiring order by I'm fairly certain I have them right.

Meanwhile, I'd like to note that my starting fluid comment may not be valid. I had the airbox and vent hoses all connected and I sprayed the starting fluid directly onto the carbs. I did not have access to the intake's since the carbs were fully installed.

Bunty27 wrote: ...my starting fluid comment may not be valid. I had the airbox and vent hoses all connected and I sprayed the starting fluid directly onto the carbs. I did not have access to the intake's since the carbs were fully installed.

Perhaps could remove the air filter and spray toward the carb intakes while attempting to start the engine.
Might help to open the throttle momentarily while spraying and cranking to increase amount of spray being sucked into the combustion chambers.
Or spray into each vacuum nipple before spinning over the engine.

Could also remove a spark plug immediately after an unsuccessful attempt at starting the engine to determine whether there's evidence of fuel on the plug tip.

Good Fortune!

I did the starter fluid without the air-filter method and still nothing. I did notice fluid on the spark plugs the last time I tried this but I'll look again in the morning.

If the sparks are good, the plugs are in the right order, fuel seems to be getting to the engine and the compression is good (150 psi in each cylinder), what could be preventing the start? I hear the engine turning and during the crank and turn, I even hear some thuds from inside the engine. I'm guessing it's just from the engine turning. No????

I'm surprised that starter fluid didn't do anything. I even had the throttle open to let air into the chamber. Hmm.....I really need a few more ideas....

Could try the following:

Remove the fuel line from petcock.
Drain the carbs.
Remove spark plugs.
Spray starter fluid down into each spark plug hole.
Leave plugs out for a few minutes to allow combustion chambers to dry out.
Install brand new spark plugs.
Do NOT re-connect fuel line.

Remove the air filter and spray toward the carb intakes while attempting to start the engine.
Might help to open the throttle momentarily while spraying and cranking to increase amount of spray being sucked into the combustion chambers.

Whether or not the engine runs for a few seconds could help with future diagnosis.

Good Fortune!

Thanks much Patton.

I drained the carbs and removed the spark plugs this morning to let everything dry out inside. I'll get new spark plugs this afternoon and will try out everything you suggested with the new spark plugs and starter fluid. I'll let you know how it goes soon.