Hi everybody, Im new to the forum and have a few questions about an old atv of mine. Sorry for the long post, it has a funny twist and is worth the read [img]i/expressions/face-icon-small-wink.gif[/img]

I recently returned home from a tour of the Navy and decided to drag my old 1985 or 86 YFM200N MOTO-4 out and see if I could get it running again. It was looking really rough and had been sitting under a wood pile for about 10 years in my garage. It took me an hour just to dig the thing out.

I opened up the carb and cleaned the case and all of the jets, checked the oil and plug, and checked to see if it had gas in it. To my surprise, there was a 1/2 tank of gas in it, gas that had been in that tank since the late 90s. The front tires were rotted off completely while the back tires looked fairly new to be as old as they were. The brakes were rusted together and wouldnt move when I pulled the handle.

I put some water in the battery and hooked it up to a battery charger. I honestly didn't think the battery would be worth charging but I just wanted to see if I could get the thing running. Of course the electric start didnt work when I finally tried it, even though it made a slight clicking sound after I let the battery charge for a while. So I started trying the pull start. It had good compression, and was really trying to start up, but it just needed a little help. I opened the intake box and sprayed a generous amount of starter fluid in it. Thats when things got funny.

I tried the pull start again and bam! The beast was alive! after sitting for that long, it came to life. She was purring like I remembered from my early years of riding. I turned around to pick up the phone and call my friend when the thing had a MASSIVE backfire. The lake of starter fluid in the intake box instantly exploded, blowing fire 5 feet in the air. I wasn't ready for a fire, and had no water or extinguisher anywhere. When slinging my drink into the fire didnt work, I grabbed an old blanket and extinguished the flames.

Luckily for me, the only casualty from the fire was the intake box. The explosion cracked the box into about 5 large pieces, but left the wiring in tact. I spent all day today fixing the box with some epoxy and cleaning it out. The beast cranked up again after I had done all of that. Im going tomorrow to get some plugs, oil and an air filter. I have a few problems and maybe someone can help me.

1. Is the battery bad or is the starter bad? It charged all night and the pull start works fine. When I press the button, the starter relay assembly makes a ticking sound.

2. The reverse lever will not engage.

3. How can I tell whether it is an 85 or 86?

Thanks in advance for everyones input. Hope to hear from ya.

-Chris

 

youll need a new battery ether way, seeing that the origional is so old. and even if it is good for the moment it probly wont last long. if you press the starter button button and ther is a noise there probly isn't enough juice.

new battery

 

Alright, Im headed up to the Yamaha store tomorrow and Ill add that to my list. Hopefully thats the only thing keeping the electric start from working.

 

Anyone help me figure out what year it is? I think its an 85 but Im not sure.

 

oil, plug, fuel filter, gas, air filter all changed. Tires changed. The beast is purring!

1 problem left:

The overflow outlet on the bottom of the carb wont stop pouring gas. The engine idles great which is why this confuses me. Any thoughts?

 

if its on the bottom of the carb, mabe its there to drain the bowl? just a guess

 

Thats what I believe it is, but it doesnt just drain. Its constantly pouring gas out of it until I turn the gas line completely off. That happens whether the motor is running or not. Is this a carb problem or a tank problem or what?

 

The drain on the bottom of the carb is just that. It has a screw so that you can drain the bowl with the gas shut off. It also acts as an overflow drain, if the fuel level gets too high in the bowl the excess runs out of it. After sittin that long, the float valve may have dry rotted and is not shutting the fuel off when it reaches the proper level. Could also be trash or the float needs some adjustment.

 

royz4x4 may be on to something. i would clean the carb and check that your float is watertight. just remove the float pin and place the float in the bottom of a bucket of water. if the float is watertight it will pop up to the top immediately. if you do this and it still continues to drain id just put a skrew in the hole. but thats my opnion.

also make sure that ther is no gunk in the float valve itself.

 

Check the float, probably still good. The screw will still be in place, no reason to have ever removed it. Remove the carb from the motor and take the bottom off. Turn on the petcock to let fuel flow to it. See if you can stop the flow of fuel by manually working the float. If you can, floats out of adjustment just bend the tab up a little. If not or it's hard, the rubber seal on the end of the valve is bad.

I have a 87 200 and a 88 225 that have give me the sam trouble recently.