86 qt 50 has spark wont start

I just replaced the battery and spark plug. Tail lights, blinkers are working but it doesnt even sound like its close to starting. Is there a good place to begin looking for the problem?

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Re: 86 qt 50 has spark wont start

Have you actually checked for spark? Is there fuel on the plug after trying to start it?

Re: 86 qt 50 has spark wont start

My dad checked the spark plug cap and the connections by the battery and they had spark. I havent checked the spark plug though. Im guessing I would have to take the plug out for that right? What would be the next step if theres no problem there

Re: 86 qt 50 has spark wont start

Did you set the gap on the new plug? Is the fuel valve on? Is the kill switch in the run position? Depending on the year your key switch may say off-run, or off-start-run, if the latter make sure it is in the "start position". Did you use the choke?

Re: 86 qt 50 has spark wont start

> Jared Sherman Wrote:

> -------------------------------------------------------

> My dad checked the spark plug cap and the connections by the battery and

> they had spark. I havent checked the spark plug though. Im guessing I

> would have to take the plug out for that right? What would be the next

> step if theres no problem there

Yeah I mean the only real way to check for spark (without one of the adjustable spark testers tools) is to take the spark plug out, leave the threads touching the cylinder/head, and give it a kick or two. You should see a strong blue spark. Weak spark will turn to no spark when in the cylinder.

If that's not the issue, clean the carburetor. That is virtually guaranteed to fix your problem.

Re: 86 qt 50 has spark wont start

I cleaned the carb and it was pouring gas straight out of the drain. Installed new carb and it acted like it would start several times. Then emptied old gas and filled with new gas but no signs of starting like initially when i had the new carb on.

Is there a certain adjustment for the carbs?

Also, tried the spark plug test, didnt have problems.

Maybe important to know that i didnt have problems until the throttle cable snapped on me. i was literally pull the cable by hand to drive it to work and back. Eventually the engine started to cut out and the battery died on me. Probably unrelated but maybe if the engine cuts out its from a bad battery

Re: 86 qt 50 has spark wont start

What is the gap for the spark plug? Is there a way to bypass the kill switch?

Re: 86 qt 50 has spark wont start

Bike will run with a dead battery, but will eventually burn up the charge coil, and your rear light and blinkers may not work. Plug gap is 0.6~0.7 mm (0.024~0.028 in). Should be no need to bypass kill switch, sometimes people just forget to set it to run, I never use it just the key.

Re: 86 qt 50 has spark wont start

I attatched my craigslist add with all the parts i was going to sell it with (not running). But now im trying to get it going, i replaced the charge coil just now and im getting a little more feedback with the kickstart but still wont fully start.

Any ideas?

Also not sure about that screw on the side of the carburetor? Whats the appropriate adjustment?

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Re: 86 qt 50 has spark wont start

Do you have the key and the the switch in their appropriate setting for starting?

Also, I highly recommend downloading the free service manual and putting it to work.

http://projectmopedmanual.info/Manual_HTML/yamaha.html

Re: 86 qt 50 has spark wont start

Don't sell that bike for $200, you can fix it. Why are you checking the kill switch and shit if you have spark?

Re: 86 qt 50 has spark wont start

Sometimes the air filter on bikes left outside for months at a time get clogged so remove the air filter and try starting. No help? Sometimes critters can get inside the end of the exhaust pipe and build a home/clog. Mine was clogged with a wasp nest. Remove the exhaust pipe and try again.

Re: 86 qt 50 has spark wont start

> Stephen Keller Wrote:

> -------------------------------------------------------

> Bike will run with a dead battery, but will eventually burn up the

> charge coil, and your rear light and blinkers may not work. Plug gap is

> 0.6~0.7 mm (0.024~0.028 in). Should be no need to bypass kill switch,

> sometimes people just forget to set it to run, I never use it just the

> key.

Yep.

Re: 86 qt 50 has spark wont start

Try starting it then pull plug to see if it's wet or dry, black or white.

Take a pic.

Re: 86 qt 50 has spark wont start

> Nick Haber Wrote:

> -------------------------------------------------------

> Don't sell that bike for $200, you can fix it. Why are you checking the

> kill switch and shit if you have spark?

^ Im with Nick

Spend an afternoon or two and dont rush it

Deep breaths

Find your center

Be at one with the QT

and enjoy the day...

Re: 86 qt 50 has spark wont start

Ok ill try that

Re: 86 qt 50 has spark wont start

I took the exhaust pipe off and still no luck. I sprayed it out with an air hose, put it back on and still no luck. The oil pump and throttle lines seem to be working fine. It seems like theres just one little thing thats off

Re: 86 qt 50 has spark wont start

"Maybe important to know that i didnt have problems until the throttle cable snapped on me. i was literally pull the cable by hand to drive it to work and back. Eventually the engine started to cut out"

Did you check for broken carb needle, spring, circlip or other linkage pieces that fell into carb/engine when this happened. Also is your choke cable working properly?

Re: 86 qt 50 has spark won't start

> Jared Sherman Wrote:

> -------------------------------------------------------

> .... not sure about that screw on the side

> of the carburetor? What's the appropriate adjustment?

===============================================

Here is an article explaining the carb and it's adjustments.

Here is a picture from that article.

qt50carb-768x852.jpg

This is the way I start mine:

Bike is always on the centerstand

Petcock on (down)

Choke lever on (to the left - choke)

Key turned to "start" (middle position)

Throttle completely closed

Kick it over

Starts in 2 - 3 kicks

Sit astride the bike before turning the key to "RUN" and revving

I have learned from experience that if I have to kick it more than that, it's not going to start because it's flooded (from sitting with a slightly leaking petcock).

Here is my procedure for starting my flooded engine:

Bike is always on the centerstand

Petcock off (horizontal)

Choke lever off (to the right - run)

Key turned to "start" (middle position)

Throttle all the way open (important!)

Kick it over (many times - until it starts)

Turn the petcock on (down)

It takes me many kicks to clear the flooded cylinder but this always works.

I get on the bike, turn the key to "run" then I rev it for 15 seconds or so and it's ready to go.

Re: 86 qt 50 has spark wont start

The choke is working fine.

I tried to clean the points on it but it didnt look like the guys in the video. I just sprayed some carb cleaner and poured some gas in there. After sitting for a while i started to get some feed back while kickstarting. Up until then it didnt sound like it was trying to start. At this point i think im losing so much compression that i need to replace the gaskets and seals.

Re: 86 qt 50 has spark wont start

> Jared Sherman Wrote:

> -------------------------------------------------------

> The choke is working fine.

>

> I tried to clean the points on it but it didnt look like the guys in the

> video. I just sprayed some carb cleaner and poured some gas in there.

> After sitting for a while i started to get some feed back while

> kickstarting. Up until then it didnt sound like it was trying to start.

> At this point i think im losing so much compression that i need to

> replace the gaskets and seals.

I thought qt are cdi?

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