Can a brother get 24 hours of happiness?

85 posts in this topic

Posted

Alright brothers, so I posted a new video on Youtube that I just completed on Saturday. First little mini motovlog discussing my opinion on buying a Chinese scoot.

So now I feel EXTRA STUPID that right after wrapping up the footage, and posting the video I go for my daily ride yesterday and she wouldn't kick-over.

I checked for spark right away, yanked out the plug, (which looked mighty dry) did the ground test and confirmed spark....cool.

Compression is good, and I know this isn't official, but whenever engine is cranked oil shoots up my decompression tube as normal.

Tested the petcock, sucked on vacuum test line, and confirmed fuel is shooting out of top of petcock.

Thought it was the carb, so cleaned and re-jetted... have attempted to start with starting fluid before and after the clean and rejetting. Still nothing.

After all that I will check for spark again, but if I do get spark then am I correct that the coil, and stator are working correctly?

After that, I was thinking of checking the valve lashes (it has been 450 miles since the engine install) and check to see if my timing has jumped off somehow.

Am I way off base here?

 

 

 

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Posted

I think your headed in the right direction, are you getting it to fire at all? even for a short time? Check to ensure the spark is consistent, I've had some issues with my stock CDI going out on me giving an inconsistent spark. Hopefully you get it sorted soon. List out any other symptoms that  might help to diagnose whats going on.

 

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Posted

I had a similar experience recently -- I validated a spark but it still wouldn't fire up when I attempted to start. Went through everything (even rebuilding the carb) and still wouldn't start. Then I noticed that the grounding cable (near the starter) was loose. Tightened her up and away she went. YMMV

M

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Posted

I think your headed in the right direction, are you getting it to fire at all? even for a short time? Check to ensure the spark is consistent, I've had some issues with my stock CDI going out on me giving an inconsistent spark. Hopefully you get it sorted soon. List out any other symptoms that  might help to diagnose whats going on.

 

Nope not firing at all.

She is attempting but I never hear her burp, when you know you can gas it and she will catch.

Checking spark again right now, and putting in a new NGK. Also checking grounds MJS...

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Posted (edited)

Static Electricity will Fire the Ether.  

If it don't fire on Ether there aint no fire.

       ignition.......

Edited by pistonguy

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Posted

NGK is in there, getting spark, but I was getting spark with the stock spark plug also.

Grounds look good.

Gonna look at the valve lashes after dinner.

 

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Posted

Fuel, spark and compression, are you hitting the starter fluid straight into the carb? make sure you tighten the carb down with no air leaks. Valve lash can certainly be the culprit if too tight, I've seen it get tight and won't have the right compression. Bright blue spark (strong)? you can verify the clearance of the pick up to the flywheel magnet.

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Posted

Fuel, spark and compression, are you hitting the starter fluid straight into the carb? make sure you tighten the carb down with no air leaks. Valve lash can certainly be the culprit if too tight, I've seen it get tight and won't have the right compression. Bright blue spark (strong)? you can verify the clearance of the pick up to the flywheel magnet.

Very strong blue spark showing.

Yes directly in the carb.

After checking valves, I will check flywheel magnet also. I'm not hearing it pickup.

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Posted

Have a Auto Choke?

R U sure she's Not Flooded?

 

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Posted

Yeah, I have an auto choke on the carb.

Nope she isn't flooded.

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Posted

Well after a valve adjustment she still won't start,

I'll have to let it go until tomorrow but at least I'm still getting spark.

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Posted

Have you tried holding the throttle wide open and turn her over? If she's flooded that might get her to fire. Be careful for the jerk forward if she fires up. How much is the mixture screw turned out? It should still fire even if this is off 

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Posted

Yup, held the throttle at 1/4, 3/4, and wide open during the course of the day. Mixture screw is 2 & 1/2 turns out.

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Posted

Hmmm, this might be a long shot, recheck the cylinder head stud nuts, see if they are torqued correctly. Vibration is a hell of a thing, can cause a compression leak.

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Posted

Will do, but I'm also swapping my carb. today.. I'm truly getting stressed out. I think my stator is working but somehow my pickup coil isn't doing it's job.

Hmmm, this might be a long shot, recheck the cylinder head stud nuts, see if they are torqued correctly. Vibration is a hell of a thing, can cause a compression leak.

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Posted

Do you happen to have a timing light? If you do you can check if the ignition is firing at the right time. If you have a spare CDI, try swapping it just to rule it out.

Also try swapping the wires on the coil, its supposed to be one way but sometimes works another. Its happened to me before.

Check for any breaks in the red and black wire from the stator to the CDI, and the blue wire from the pickup to the CDI. Sometimes they get pinched and can ground out causing an intermittent spark condition.

I know how frustrating it can be, I just spent two hours pulling the clutch apart cause the 34mm nut backed out. Never happened before but last night it locked the rear tire up as I pulled in the street. I modified the clutch a little as I was in there, lol its in my nature. I ride with a full tool kit in case of any breakdowns, I make sure to have my homemade tool to remove the variator and clutch if I need to. Haven't had to use it for many months now, but I help a lot of riders on the road that are stranded.

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Posted

BCY,

No timing light.

I truly appreciate the help you have given! Also glad you didn't get hurt, tire lock up is scray!

I was just reading on some of the older posts about swapping the wires to the coil and will be trying that.

I have 2 CDI's and have swapped them back and forth. Getting spark with the stock one only, but that was what I had been running on of the last month.

I have noticed quick build up of battery corrision on the negative terminals. I am swapping out with a new battery after cleaning the terminal....but most likely not the problem though,  I have a jumper power bank I have used. I can always get enough power.

I am going to check my ground to the motor with a multi-meter, put in new fuel, and swap back to the stock carb today.

My bday is in 5 days and I WILL BE RIDING!    %#&% this #@$^

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Posted

Thats what we are here for brother, we all have to help each other out. 

I've learned some much from everyone here, I hope you get her back up and running soon. Let us know how it goes. 

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Posted

Thanks BCY and also, thank you so much for subscribing to my channel.

I really appreciate it!

I won't let you down, we will be back on the rode soon.

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Posted

Well it not the carb. I replaced with the original and still won't start.

Still getting spark, fuel and compression.

Could my stator be good, but my pickup coil bad?

I'm thinking the stator is working because I'm getting spark.

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Posted

Well it not the carb. I replaced with the original and still won't start.

Still getting spark, fuel and compression.

Could my stator be good, but my pickup coil bad?

I'm thinking the stator is working because I'm getting spark.

If pickup where bad you wouldn't get spark, looks to me like it needs a valve lash adjustment, or that the timing chain is off a tooth or two.

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Posted

 

I checked for spark right away, yanked out the plug, (which looked mighty dry) did the ground test and confirmed spark....cool.

Compression is good, and I know this isn't official, but whenever engine is cranked oil shoots up my decompression tube as normal.

 

Okay, you may wanna do an actual compression test... I can't tell ya the amount of people that stick a finger on the spark plug hole (with the plug out of course) and try and check for compression.... What people fail to realize is just because there's compression, doesn't mean it's enough... For instance, you might be at 90psi.... NOT ENOUGH... Upwards of 170PSI+ is where ya wanna to be at.

These single cylinder engines are about as basic as you can get.... If you're getting fuel, air and spark, doesn't leave many more things to check... Has to be something like valve lash, weak PSI, or your air fuel ratio is way off.... Or like MJ suggest, the engine ground. 

Provide more details... Did this happen all at once? Or has the engine been getting harder to start each time? 

 

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Posted (edited)

Dan is on point here Kachi, compression is the only thing left. At least for it to fire over.

Did you get a chance to check the cylinder head stud nuts for proper torque? I've seen this happen many times especially where I am, people that don't have torque wrenches and no building experience either over tighten or barely snug the head nuts. f not torqued properly, vibration can cause those nuts to back out over time.  

I'm looking over your build video to see if I see anything that may give us a clue.

Edited by bcyprian25

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Posted

This is mine from a couple years ago.

 

DSCN0945.jpg

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Posted

Kachi, did you do a leak down on that Glixal head before you installed it to ensure the valves are seated correctly? 

When I got my first Glixal head the valves leaked, so I had to spend about an hour lapping them. I ended up at the machine shop to recut the seat cause it was just way off and then lapped them back in.

 I'm not saying this is the problem but it might be a candidate. this is due to how these heads are assembled, we are not sure of the quality control, the seat is cut in one process and the valve might just be dropped in. If there is anything off at all this can cause a compression leak. 

This also applies to the automotive aftermarket, I've seen videos of AFR and DART heads that leak. I'm sure Piston will have more info on this

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