Hello all, my buddy has a 84 Honda ATC 70, we are tryen to get it running for his kid. We have GREAT spark, get PLENTY of gas, but won't fire over
1. First ? can the points and condensor be bad and still have spark?

2. Second, I think at least part of the problem if not the only problem is the Kill switch wiring. Is there any way to just wire the atc temporarily so that it is in the "On" position FOR SURE, just to test the switch itself? Is there any good pics of the wiring schematics for this, preferably someone who has taken pics of the wiring on an actual ATC.


All help is GREATLY APPRICIATED, I am truly thankful for the WEALTH of knowledge here!

 

the kill switch just plugs in under the tank,,,, green and black wire,,, unplug them both,,,, you are now ON only,,, if you have spark and fuel,,, it should run... how much compression does it have? that would be the only thing not letting it start,,, aircleaner good?

 

Ok, so simply cut the two wires leading up to the kill switch, tape the end off on the wires, and now its in "On" only? Now how will I turn it off? thanks SO much for the response, and NICE -*** ATC'S you got , KILLER!!!!!!!!!!

 

do not cut the wires, unplug them. and if that doesnt work, the the timing could be off. either on the points end or the cam end of things. most likely the points end unless someone has had the head off before. a manual will clear up how to test the points timing.

 

If it has "GREAT spark" I don't know why your checking points/condensor or the kill switch .. Remove the plug cap (threads off) hold the plug wire about 1/4" from the cylinder head and crank it over , if the spark jumps the 1/4" it has good fire . .

 

Ok, the spark is really good, and it seemed to be really good when the kill switch was in the "off" position or the "on" position. Now this seems IMPOSSIBLE to me, but can the points/condensor be bad if i have good spark? I would think the fact that I have good spark means that the points/condensor is good, correct? So lets assume that spark is good, and the kill switch is fine (it isn't), what else could prohibit it from running? I do not have a working pull starter right now (waiting on the inerds to rebuild my broken one) so i am tring to start it with a drill ( I know this isn't the best way to do it). Could it be that I am not turning it fast enough with the drill? I am also definately getting gas on the plug, and you can feel air coming out the exhaust, blows your thumb off the plug hole even with full pressure (again I understand this is not a way to test compression), We have a BRAND NEW set of points and condensor, just waiting on the puller. New plug, FRESH gas, air cleaner sock is good. What should I do with the air and fuel screws? Assume they are correct and continue trying to start it? or tighten them all the way in and back out to a specific amount of turns???? Any help to get this running is SOOOOOOOOOO APPRICIATED.

 

As Kasey stated earlier the three basic things your engine needs to fire are spark compression and fuel. So it would seem logical to do a compression test (if you don't have a tester then they should only run you about $15-$20 at a parts store. Anything over 100 PSI is Easily good enough. If that doesn't work you could check the timing although it would have to be really out of whack to not even start. Also, when my pullstater was broken I put my trike in 3rd gear and pushed in down the hill to start it, that my be easier to do. And if your spinning it over with a drill is it possible that your cranking it the wrong way? it should be counter clockwise, and I wouldn't imagine that spinning it the wrong way would have any effect on the spark so it could be possible.

 

Tried the pushing deal, pretty savy with that. Definately checked the direction of the flywheel per the arrow on the flywheel (yes counterclockwise). I guess I would need to grab a compression tester, so anything over 100psi? Is there a more exact number to shoot for? Thanks again for all these responses!

 

Pushing a lil 70 in third gear shouldn't be too bad, unless you have MAD compression, which doens't quite make sense. Maybe your oil pressure is low or no little oil at all, did you check that? a simple oil change never hurt anything, just pull the engine over a few times after you drain the oil especially if its been awhile since last changed to get it all out, if you do decide to change oil.

I'm pretty sure that right off the showroom floor the compression should be 156PSI +/- 14. so a range of about 140 to 170. But its pretty normal to have lower than that on a well used trike. Ive seen trikes run with as little as 85PSI, but performance takes a big hit. Also, remember that when doing a compression test, keep pulling it over until the compression reaches the maximum, not just after one pull or something like that. But i warn you, it can be a knuckle buster!

 

Sounds GOOD! So could I incorporate the use of the drill here to continually turn it over? Getting the tester is easy enough, so if I have compression, fuel, spark and air, then it HAS to run right? So how will I go about turning it off? If I unplug both the wires from the kill switch, then that is a "ON ALL THE TIME" deal, so if I simply put an "on" "off" toggle in between then I should be able to shut it off right? Anything else besides changing the oil? I thought I saw in a manual somewhere that your supposed to remove one of the side covers and wipe something off to properly change the oil in the 70, is this true? If so then a cover gasket would then be needed correct? I understand to pull it several times to get all the oil out, but this said to take off one of the engine covers as well? I was gonna run Valvoline "Motorcycle" 10w40, that seem good? Is there only one drain plug for the oil? Can the Trans fluid be changed? Does it use seperate trans fluid? How often do you change it? TONS of questions, just wanna get this thing running right, oh yeah, recommendations on the carb setting? Is there a "default" setting I can try like tighten, then loosen 1 and a half turns, etc. Thanks again!!!!!!BLAZZZZZZING FAST RESPONSE!