NOOB.....ATC200S Problems

[usmcgunnerm4]

Hi all,
brand new to the forum. I've been a triker for awhile, but just recently took on a project. I got a 1985 ATC200S that was running clean....fast....steady....with no problems. THEN.....I ran it out of gas. Booooooo. Hasn't run since. So, here it is in a nutshell, and I am fearing the worst.

Its a 4 stroke motor, and it looks like the carb is relatively new. Very clean.
1. I put brand new gas in it, cranked it 30-40 times, nothing.
2. Getting good blue spark on a new plug.
3. Carb is adjusted to 1.5-2 turns out
4. No rust in the tank

All of those things seem to be in order, now for the tricky parts.

I got it to fire this morning, it ran for about 2 minutes, but only if I held the throttle at about a quarter. Any less and it would sputter. I tried to start it again and intermittently the pull starter seizes up just before exhaust. This is only under compression. If I pull the plug out, it's easy cheesy. I pulled the recoil out, and it works just fine. Note: It did not do this before I ran it out of gas. I may have sucked up some debris from the tank.

The previous owner said that he had not changed the oil in a year or two (didn't ride it much), and that it had been sitting without a lot of care. I changed the oil and cleaned the filters. Lots of sludge. I even took a long swab through the spark plug hole, and was able to pull a tip of gritty black sludge out 2-3 times.

So, I figure that I have a sludged up top end, but it is more like the valve is sticking, and the cam has to be forced over. However it's only when it is under compression.

I have heard about filling the crankcase with kerosene and cranking it 25-40 times (repeat until clear fluid drains.) but I am wondering if that will help the top end? I really like this gal, and I will tear the engine apart if needed, but I would like to have her running before our trip to the mountains in 2 weeks.

Any advice? Suggestions? I am planning on making this a restoration, but it is going to be a daily rider until I save the money. Of course, I may not have a choice now!

GREAT FORUM GUYS!!! I'll be around.

[freewheel3]

Do a compression test. This will tell you instantly if you have a valve sticking closed (by a high compression reading), or whether something is just binding up.

[usmcgunnerm4]

Gotcha. I have to buy an adapter set. I have the gauge, but nothing to screw in to the hole. Any idea what else would be causing sticky turnover?

[money89tractors]

could also just pull the valve cover off and see if its sticking.

-Phil

[usmcgunnerm4]

Valve Cover:
Being that I am a newbie to these guys....I pulled off the plug in the front of the top end (compression relief?), and I could see only one valve, but it was moving smoothly. I haven't gone too much farther, but here is what I have done so far:

Pulled the tank, air filter box, and carb. All appear to be clean, clear, and working. So.....I am guessing I have some gunk that is binding the motor. I am going to put it all back together. BTW, I sprayed some sovent into the hole in the front, and the binding went away. I would say that my problem is in the valves. So.....for a guy who doesn't have much time or money to invest immediately....suggestions?

[MTS]

You physically rip the carb down and clean it...? other than that i would think i snapped/and or stuck/ decompresser/ cable off the top of my head, haven't had one in 5 yrs

[usmcgunnerm4]

Took the carb off (haven't torn it down yet). Still had the same problem. Only time it doesn't do it is when the plug is out. BUT, it seems to be cranking free since I put the solvent in the top end.

[usmcgunnerm4]

snapped/and or stuck/ decompresser/ cable off the top of my head

Can you explain how I might check that. Reading the manual I find nothing with those exact terms. Maybe I'm not looking hard enough.

[usmcgunnerm4]

Nevermind, I misread it. for some reason I thought you said compressor cable.... My bad. It is free and functional.

[usmcgunnerm4]

Update:

I figured out the stickiness problem. It was the decompressor lever. THANKS!

Now, the carburator seems to be giving me trouble. I get the beast to fire, and run, but only if I adjust the mixture ALL THE WAY RICH! Then (of course) I am getting plumes of white smoke billowing from her behind. I'm working on that one, tearing her apart again today. Will keep you posted.

Ian

[usmcgunnerm4]

Oh yeah,
and it seems that the factory gap isn't enough for her. I gapped it out to .35 before she would fire.

[oscarmayer]

i would say the carb got junk in it. just because you didn;t see rust doesn't mean it's not there or junk isn't in the tank. drain the tank and flush it.
check to see if you have a fuel filter. if not install one. if you do, chagne it out.
on the carb, take the bowl off and use carb cleaner and spray the dickens out of bottom of the carb and the bowl. clean it completely.

i think if you do that it will work fine after.

[roger86200x]

it seems that every time my 200s has a problem starting or running right its a stuck float valve... I just tap on the carb and boom....it fires right up.

Also, did you try using starting fluid to get it running an pump the gas through the carb?? If mine goes below reserve and stalls out i HAVE to use the starting fluid to get it going again, no matter how many times i pull it....its like there is "air" in the fuel line or something, lol......

hope it helps

Roger

[usmcgunnerm4]

Hey!

Great ideas guys. I haven't had time to work on it since Wednesday, but I am going to get her going today. I have the day off. I am going to rip the carb apart again, and use some of my handy carb cleaner to drench it. The tank is going to come off anyway, so I will clean it out also. I have a feeling that the "air in the line" scenario is exactly what happened to me, only a few more problems crept in. Thanks for the help guys!

[Erics350x]

run a stran of wire through the jets