ATC 70 No spark.... UPDATE 12-1-08.. We have life!!

[Mosh]

74 atc 70 no spark. Engine is a 83.
Checked the points and they were siezed. Wouldnt move.
So I swapped the good points out of the 74 engine. and eyeballed the gap.
About .017" at the "T" mark. Even if the gap is not correct, shouldnt I get something?
So then I take the plug out of the engine, install a spark tester,and I spin the flywheel over by hand,and still no spark.

I am pretty sure the coil and switch is good,as the 74 motor sparked before I pulled it,but had a valve hanging open so that is why I just went with the 83 engine.I also disconected the kill switch wire to check,and no spark either way.

Could one of the stator coils be bad?
Any testing specs Someone can offer?
I dont have the manual yet.Waiting for one.

[blue27]

I have found that points go bad. Replace them, I have tried filing them, cleaning and regapping and the only thing that works is new ones. And here is a online copy of a generic repair manual. Page 25

http://www.intheredgraphix.com/hosted/Honda_ATC.pdf

[Mosh]

Ok thanks for the link.

Are the points generic?
Meaning, can I go get some for a Old snow blower or something at a local place?
Or do I have to buy them somwhere special?

[blue27]

I do not know if you could make something work, I order mine from Sudco, they come with the condenser and points in a kit. I do know they are the same as most z50s and CT70s. I always have a set in inventory here but I don't think you want to drive that far,lol. Good luck

[sandpuppi101]

Are the points generic?
Meaning, can I go get some for a Old snow blower or something at a local place?
Or do I have to buy them somwhere special?

I don't know if there generic type point's Mosh ,but I usually buy a dozen at a time when I get them ,but I order them specifically for the 70's,but anyway's you'll notice on a set of worn point's that at the contact point ,it will actually be wore at an angle.I alway's just replace them ,it's a cheap fix and I'd rather just be done with anything point's related.(It's bad enough the way you have to adjust them with the magnet in there, it's frusterating enough, JOY-JOY !!)Anyway's it's .012-.016 spec's on them,but if your in the ballpark you should get something.Have you looked at the woodruff key good on the flywheel/crank? You should look at that for wear and see if it spun..

To check the innard's ( meaning stator-point's) ,I usually put a drill or airgun, on the end of the crank,on the 14mm or 17mm head nut,and turn the motor over . Remember: Turn the motor over counterclockwise ,and make sure you take the spark plug out also.

Check the wire coming out of the case,from the stator.Use a test light and see if you have any juice coming from there.Put an ohm on the on/off and make sure you have resistance. If that's good check the coil with the ohm and see if you come up with anything.If you get better than ,I think 2.8 you should be good..Make sure you check to make sure it's grounded also,been burned on that before,Stupid ! That's eletrical,but something you should check is vacum.

By checking vacum,I usually have the motor turning over and while it is turning, I cup my hand over the carb and see if I can feel any suction. By doing that your checking your valve's and you'll see if there is enough suction for drawing gas out of the carb.

Hope that help's ya out some,I've worked on so many of these little guy's that I've got everything pretty much memorized ,it seem's,lol.Mosh,that's just the usual stuff that I check out first.Anything else I can help ya with just let me know..

[Mosh]

Thanks for the tips.

I guess I am on the search for points.
The ones I installed worked before.
So that is why I am confused.
I am thinking something else is wrong.
The coil wire is destroyed,but it sparked with the orginal 74 engine, the one with the burnt valve.
I swapped in this 83 motor in the 74 frame, and no spark now.Those 83 points were junk,so i swapped out the 74 points, which have some wear,but look fine and was triggering spark before I pulled the 74 motor.

The woodriff key is fine, the engine mechanicals are good.

I will ohm the stator and try the checks.

In the meantime,
are the stators all the same? are the coils all the same for all years of the 70?
The way this coil wire looks, I am gonna have to replace it anyhow.

Maybe I will swap the 74 stator and retry it,if I can use that 74 stator in the 83 motor.
Thanks again.

[dizasterzrfun69]

i believe the points are supposed to be set at .012" -.016" i thought the points were bad an my 82 (might be 83) so i reset the gap and still had nothing, i grabbed the black stator wire to test my condenser and that black wire had come unplugged :crazy:

[Preddy05]

My 85 70 had no spark so i replaced the stator and that fixed my problem.

[Dirtcrasher]

Honestly, my 70 has been pissin me off :lol: I guess I just don't have the patience right now....

I sanded the worn points, had to oval out the mounting hole to get about .015 and I got it running.

It still ran like crap and would die about 5 minutes into the ride. So, I ordered a carb kit, but Bikerbeyatch's kit runs till 1983 and not 85 which is mine. I grabbed points and condensor at the same time.

So, I got it running and used whatever carb parts I could to partially rebuild it but it's still screwed up.

I won a 79 atc70 today for 51$ :w00t: so I gotta get it figured out sooner or later. I think there just all old and tired and they can't be half arsed so I guess I have to put effort into it and then I'll get it. I think I'm just to excited to play around on it that I don't take the time to get it right!

Good luck with yours!!

[mdunn]

If the points are not it, take off the spark plug wire and cut a little off of each end. It gets corroded from the heat and arcing. If that doesn't work, check the coil. My '85 was just doing the same thing, and a $25 coil did the trick. Good luck.

[The Goat]

They sell quality cdi conversions now for the 70s.

I'm on my phone so google Honda 70 cdi

It's a site called mx something. About 50 bucks, half the price of mine from Malaysia...

[The Goat]

It replaces the entire stator plate. As an added bonus.

[atctim]

Mosh - you prolly know about this - but if not here is a super source for 70 parts

www.dratv.com

they ship super fast and are pretty reasonably priced.

Just found this there as well - maybe could help you out

http://us.st12.yimg.com/us.st.yimg.com/I/dratv_2028_69131365

[Mosh]

Thanks for the help guys.Goin to try to attack this this coming weekend.

I will get back to you once it is solved.

Yeah these little things are finicky, but man once they run good,they are fun as hell.

[Dirtcrasher]

ATCTIM, just that diagram is very helpful! Thank you!

Talk about pot calling the kettle black :lol: I don't have a manual yet :rolleyes: - gotta find the online one...

Do you guys have faith in the points setup? or is swapping to a CDI a better bet? I honestly wonder if the cam on the crank is worn and affects the dwell of the points...... At that point, I'd have to run a CDI.

My 51$ seller won't respond to me, I don't think he's very happy......

[atctim]

Do you guys have faith in the points setup? or is swapping to a CDI a better bet? I honestly wonder if the cam on the crank is worn and affects the dwell of the points...... At that point, I'd have to run a CDI.



Not to get off the original topic here - but in my honest opinion, I find it much easier to trouble shoot a points motor than a CDI motor. I have plenty of points machines - I have much faith in them.

[Mosh]

I dont have any complaints with the stock ignition for these as well.
The 83, 70 We have hauls the flippin mail,all bone stock.Just trying to put the 74 back on the trail.It never ran when I got it, The frame was bent but it was all original and solid.Just got to get it fired off now.

And yes the diagram rocks Tim..Thanks

So can I swap the 74 stator into the 83 engine?
Are they the same?

[Mosh]

Ok good news....

I want to thank Mark......My bro.....
I have been too busy to get anything done, so he came over and loaded up the 70 and took it home.

As the consensus said, the points were bad, as well as the coil.
Mark Got me fixed up with the points and some other little parts I needed, and now I just have to finish final assembly..
Anyone have a good place to get a throttle cable and brake cable for this 74 ATC 70?

Or is there a 400ex or something, throttle conversion I could use?

I am gonna try to upload some pics here in the next few days.

[cybrman]

I just recently purchased some stuff here. Very fast shipping was 3 days at my door.

http://dratv.com/bodyparts.html

Just realized the throttle cable says 78-85.....hmmm how different can they be?
Then again you also have an 83 engine so I'm guessing this should work. Can find no diagrams pre 78

[iamschme]

Yeah the web site is www.re-mx.com go under the mr50 parts and you will see a cdi for $45. all you do is remove your points and condenser, and connect the wire from the ignition coil into the black wire that goes to your coil up top. (there are instructions on the site, super easy) then it is just bolt on the little cdi and it works. I didn't have to make any additional modifications. it took all of about 15 min to do.

[stg1dom]

Hi everyone, a newbie here. I did a search and found this post. I am interested in this CDI conversion on my 1984 ATC 70. I have replced the points, condensor, and coil. I still have no spark. checked the on/off switch, its good. As for the stator it seems like I have continuity between ground and the black (hot wire). So I am assuming the stator is bad possibly internally. I don't see any broken wires in the harness either. I went on this site but it doesn't say anything about atc 70's. http://www.re-mx.com/mr50/mr50parts.php Does anyone know if this CDI unit is the same?

[stl_ed]

Hi everyone, a newbie here. I did a search and found this post. I am interested in this CDI conversion on my 1984 ATC 70. I have replced the points, condensor, and coil. I still have no spark. checked the on/off switch, its good. As for the stator it seems like I have continuity between ground and the black (hot wire). So I am assuming the stator is bad possibly internally. I don't see any broken wires in the harness either. I went on this site but it doesn't say anything about atc 70's. http://www.re-mx.com/mr50/mr50parts.php Does anyone know if this CDI unit is the same?

Try this one for half the price. Ive seen em as low as $14

http://www.jackssmallengines.com/ignition_b.cfm

[86trizinger]

They are like $20 from Jack's.. I drive by there everyday if anyone ever needs one.