I need ignition help

[RyanSzpara]

I just jointed DRN and so far seems awesome. Anyway...I have a 1973 Yamaha DT3 250 (2-stroke) vin number DT1F-159148.
Last summer the bike ran okay then sat all winter. This summer i tryed to get it running again and it wont get spark. I replaced the leaking crank seal and put new points and a condenser in . I gaped the points properly and still no spark. Do i need a new coil? how do i test it? what else do i do ? Any help will be awesome


Thanks

PS the bike WAS electric start but has since lost the battery and all the lights -- It ran like that last year too. Maybe wire diags would help?

Bad Stator maybe?? How much $$$ are we talkin ??

I tested the coil and got 1.1 ohms primary (spec is .6 ) and 5.72Kohms secondary (spec is 6K ohms) is this coil bad?????

How do i test a stator

 

[RyanSzpara]

uhh......anything?

 

[Uchytil]

Ryan, Hard to diagnose here. A manual would be a big help for you. Did you do the simple stuff? Is the kill switch stuck? Try disconnecting it. A new plug? Go through all the wires and check for good connections. A friends steert bike I had a go with sat for a few years and two plud connectors corroded. I replaced them and presto! Sorry, don't have the specs on that beast.

 

[billc]

Get a repair manual!

Ryan,you need to get a repair manual to get your bike running.Those bikes never had e-start,they have magnetos!Back in those days we always got rid of the battery and all the extra turn signal crap,etc.It went in the trash!
Don't rely on this forum.Get the manual,some tools,and an old fart that knows his stuff,and you will be on your way!

 

[RyanSzpara]

am i retarded??

thanks man......i do have a manual ......its kinda helpful. I tested the coil like i said earlier and got those readings posted earlier......then went to the stator......i get continuity between all three windings but i think im getting continuity to ground as well......i hope my stator isnt gone.....im just so lost because there are way too many wires just chillin due to the fact that i ripped all the accesories off. Also, the ignition key never worked so there is no kill switch....any ideas??


Hopefully i dont have to spend a lot on this thing because it was given to me .......but it ran last year !!


Thanks again

 

[billc]

It has been almost 30 years since I worked on one of those so I have forgotten alot.Just do the basics as you would do with any engine...
I think that bike will run without much work.And I don't think there is anything wrong with your stator,etc. Those bikes were very simple, didn't have computers,and were reliable.
Use a brand new spark plug.(Get two.)
Make double sure the points& timing are set right.
Make sure it's getting fuel.(fresh fuel)
Got compression?
Does it still have Autolube?
The + side of your coil has to get electricity in order for the coil to make a spark.It should get it when you kick it over.
It ran fine last year so I am confident that it will start for you unless you have undone something that you're not telling us about. Sorry,but it's not easy to diagnose via the computer.

 

[RyanSzpara]

thanks for helping me......its got 125 PSI for compression
It is auto lube
im going to recheck the timing...again

Thanks man


Im not having a lot of time to work on it lately but im trying.

I appreciate your help and ill keep you posted

 

[Ol'89r]

Last summer the bike ran okay then sat all winter. This summer i tryed to get it running again and it wont get spark. I replaced the leaking crank seal and put new points and a condenser in . I gaped the points properly and still no spark.

Ryan.

Have you tried a new spark plug? A plug can become fouled to the point that it will not fire even if you clean it.

Like billc said, make sure the points and timing are set right and also, make sure the points are very clean. Even if they are new, make sure they are clean.

If it sat all winter, your pilot jet may be clogged. Did you remove the float bowl and clean out the carb? If not, remove the jets and make sure you can see daylight through the pilot jet. Gas turns to lacquer when it sits for a long time. This will clog the little passageways in the carb.

If it ran ok the last time you rode it, nothing in the ignition should have changed. Other than corrosion on the points or plug cap.

Just my $ .02

 

[RyanSzpara]

yeah.....i have a new plug in it.....and i rebuilt the carb and replaced the crank seal......if my points arent gapped perfectly will it get ZERO spark or will i maybe see some?

Thanks so much for you $.02 .....i appreciate all of the help



Thanks


PS - does anyone know of a place (dunes to ride in michigan thats open later than OCT 31 ?? i know this isnt where i post to ask but i thought id just PS it )


Thank you

 

[Ol'89r]

if my points arent gapped perfectly will it get ZERO spark or will i maybe see some?

Ryan.

It is very important to have the points and the timing correct. With a magnito ignition system, you can move the ignition 'out-of-phase' by having the points gapped wrong or the timing off.

In other words, the points have to break at the same time the mag produces electrical energy. The mag produces energy in pulses. The points have to open at the same time as one of the energy pulsation's. If they are off, you will get either a weak spark or no spark. Another thing to check, pull the flywheel off and make sure the woodruf key is not sheared on the crank. This can throw the system out of phase.

$ .04 now :cool:

 

[RyanSzpara]

thanks,

The woodruf key is in good shape, but i am not 100% sure i am gapping the points perfectly (its hard to fit the feeler gauge through the view hole on the mag) what else (besides gapping the points) should i do??


Thank you

I owe you for your help (worth a lot more that $.04)

thanks

 

[billc]

Yes,sometimes it's not easy to gap the points.I used the non magnetic feeler gauges to get a better feel.
I bet that old bike is very close to running.New plug? New gas? Got spark? Don't flood it! It should fart at least...

 

[RyanSzpara]

thanks

Hope its close to running --(non magnetic feeler gauges ?? are they just aluminum or sumthing?)

Thanks for your help

 

[billc]

They're brass/copper material = non magnetic.So the flywheel(magneto) won't give you an inaccurate feel when you're trying to set the points.
It will run,I know you're close!

 

[RyanSzpara]

thanks


Im going to go to get some new feeler gauges tonight and try that out ......
Thanks

 

[Ol'89r]

what else (besides gapping the points) should i do??
thanks

Ryan.

Do a rough check on the timing. I can't remember the exact timing for that bike, but it's probably around 2mm btdc.

Remove the spark plug and insert a thin rod down the plug hole. Rotate the flywheel until the piston is at tdc and mark the rod. Make another mark on the rod 2mm above the first mark and back the piston down to the second mark. It's best to use a dial indicator for this but, if you don't have one you can use the rod method.

With a ohm meter attached to the ignition wire rotate the engine until the piston comes up to the first mark or the 2mm btdc mark. The points should break at the 2mm mark. If they don't, adjust the points or the backing plate until they do.

This should put you in the ballpark. :cool:

 

[RyanSzpara]

wow thanks for the tip Ol'89r .

i thought i heard something about needing to use a dial indicator ( o dont have one) but never thought to use a rod. THanks again.


where do i measure with the ohmeter and what if the points dont open at 2mm????

thanks for the help

 

[Ol'89r]

where do i measure with the ohmeter and what if the points dont open at 2mm????

Ryan.

If I remember correctly, (which is very unlikely) :yikes: you have to clip one lead of the ohm meter directly to the points through the slot in the flywheel. Since it is a magnito, you will only notice a slight difference in ohm's when the points break. Not a complete open circut. Be careful not to let the clip touch the edges of the flywheel slot or you will get a false reading.

You can also use a piece of cellophane from a pack of cigarettes. Place the cellophane between the points and when they break it will release the cellophane.

If they don't break at the right time, adjust the points until they do. If you can't get the right timing by adjusting the points, you will probably have to remove the flywheel and adjust the point plate itself.

Keep in mind this is just a rough check and should be done with a dial indicator to be accurate. :cool:

 

[Coop37]

I am almost positive the battery has to be in on the electric start models! the non electric start bikes you could run with out a battery, but the electric start stator type need 12 volts!
I have a electric start ycs1 with the electro magnetic starter on the l.h side of the crank ( which is the same as yours I believe) mine has a red light on the speedo that comes on when the voltage is bad. see if yours does. but just for kicks, hook up the battery.

 

[RyanSzpara]

well.....turns out the battery is history.....can only get it to hold like 2 volts for a while.....it ran last year with the battery hooked up but with no charge.....hmm

thanks for your help guys

(ive been too busy to check the points again)

Thanks

 

[Coop37]

Just put 12 volts to it. And see what happens. the battery may have had more voltage last year.. I think it will run with 9.5 volts but no less.

 

[RyanSzpara]

just hook up a 12 volt (like car battery) to it? will that work, or use like a charger?........ thanks

 

[Coop37]

car battery will work fine for the test.
Let me know

 

[RyanSzpara]

cool .....will do ..........thanks man