[Ucantbobmyknob]

I am working on my brother's 06 400ex and I am having issues. A few months back he was riding acrossed a field and the ATV just shut off on him. We figured it was something electrical because everything still works (lights/starter/etc.) so we just rode the other quads and let it sit. Well Yesterday I tried starting it and it is getting fuel to the carb, and spark to the plug, but it is not turning over. It backfired one time but that was it. I replaced the plug and still nothing. Then I pulled out the new plug and it wasn't wet (I figured it should have been with all the attempts to start it). Everything seems to be working okay and trying to turn over, it's just not. I'm lost on what to do now. :dry: Any suggestions would be appreciated! Thanks -Brad

 

[Helmut]

I am working on my brother's 06 400ex and I am having issues. A few months back he was riding acrossed a field and the ATV just shut off on him. We figured it was something electrical because everything still works (lights/starter/etc.) so we just rode the other quads and let it sit. Well Yesterday I tried starting it and it is getting fuel to the carb, and spark to the plug, but it is not turning over. It backfired one time but that was it. I replaced the plug and still nothing. Then I pulled out the new plug and it wasn't wet (I figured it should have been with all the attempts to start it). Everything seems to be working okay and trying to turn over, it's just not. I'm lost on what to do now. :dry: Any suggestions would be appreciated! Thanks -Brad

Sounds like the carb is stopped up. Pour about a teaspoon of gas down in the spark plug hole. Quickly, put the spark plug back in before the gas evaporates. Try to start it. It should start and run for about 2 or 3 seconds. If it does the carb is stopped up and you will need to take it off and clean it.

 

[Ucantbobmyknob]

I dropped a little bit of gas in the plug earlier, it wasnt all that much tho. And I wasnt quick putting the plug back in. I will try it again. could it be a compression issue or possible blown motor? and is there an easy way to test the compression?

 

[t-rex]

i had a blaster that just shut off on me.i poured gas in the plug hole and kicked it over forever it backfired a few times.it ended up being the base gasket was blown out.

 

[Helmut]

I dropped a little bit of gas in the plug earlier, it wasnt all that much tho. And I wasnt quick putting the plug back in. I will try it again. could it be a compression issue or possible blown motor? and is there an easy way to test the compression?

You can test the compression with a compression tester. If the plug is dry, you are not getting any gas to the cylinder.

 

[Helmut]

i had a blaster that just shut off on me.i poured gas in the plug hole and kicked it over forever it backfired a few times.it ended up being the base gasket was blown out.

A 4 stroke isn't like a 2 stroke. A leaking base gasket on a 4 stroke won't cause it not to run. It will just cause it to leak oil.

 

[Billy250X]

Could have jumped time.Just a guess though.

 

[Helmut]

Yeah, it could have jumped time. Check and see if it's firing at the plug. If it is, pour about a teaspoon of gas down the spark plug hole and put the plug back in and see if it will start. If it don't, there's a good possibility it jumped time or you have another problem inside the engine. Is this the one that had the gas mixed with oil put in it? If it is, make sure the plug is good. It may have fouled the plug.

 

[shadetree]

easier way to check if it's a carb prob..can of sarting fluid in the carb.., < very short sprays >..if it runs for a few seconds..it's the carb..if it don't..it's a compression issue.

 

[Helmut]

easier way to check if it's a carb prob..can of sarting fluid in the carb.., < very short sprays >..if it runs for a few seconds..it's the carb..if it don't..it's a compression issue.

Yeah, you can do it that way, but I just never liked using starting fluid in an engine. It can wash the oil off the rings and cylinder walls. You can put gas in a spray bottle and spray it back in there if you don't want to use starting fluid.

 

[shadetree]

true helmut..i just spray the starting fliud in thier real short burst..nothing heavy..just enough to tell me it's a carb prob or compression

 

[Helmut]

true helmut..i just spray the starting fliud in thier real short burst..nothing heavy..just enough to tell me it's a carb prob or compression

Yeah, it probably wouldn't hurt it, unless you sprayed a whole lot in it. I'm just overly particular sometimes. LOL.

 

[mud99]

I herd someone mention vapor lock by using ether any truth to that??

 

[Helmut]

I herd someone mention vapor lock by using ether any truth to that??

I've never heard of that before. Maybe they sprayed the cylinder full. I have seen automobiles lock up from too much gas in the cylinder. Gas compresses, but if the whole cylinder is full, it won't. It has to have a certain amount of air, before it can compress in the cylinder. Ether would probably work the same way. Maybe they sprayed to much ether into the cylinder or something.

 

[mud99]

I had never heard of it either but thats what he said. It was on a motorcycle.

 

[Helmut]

Vapor lock really means that the gas gets hot and turns into a vapor in a fuel line and stops the fuel pump from pumping it properly. I don't see how he could have had vapor lock with ether unless he was trying to run straight ether in the bike. Maybe he meant something else by vapor lock and was just calling it that. I don't know.

 

[shadetree]

never heard of a vapor lock in a atv..i've worked on them for over 12 years..and never seen or had it happen to me..now.on a car..or truck..yeah..atv..motor cycle..no.

 

[mud99]

never heard of a vapor lock in a atv..i've worked on them for over 12 years..and never seen or had it happen to me..now.on a car..or truck..yeah..atv..motor cycle..no.

I was just repeating what the guy told me. I had never heard of it either. I would say he didnt know what he was talking about.:icon_ banana:

 

[Billy250X]

Yeah probably not.lol

 

[Ucantbobmyknob]

Yeah, it could have jumped time. Check and see if it's firing at the plug. If it is, pour about a teaspoon of gas down the spark plug hole and put the plug back in and see if it will start. If it don't, there's a good possibility it jumped time or you have another problem inside the engine. Is this the one that had the gas mixed with oil put in it? If it is, make sure the plug is good. It may have fouled the plug.

No the one that had the gas oil mix in it was the other one that I have the big bore kit coming for. I put another plug in the wire and it sparks to the frame. I tried the gas in the plug hole and I got nothing. Timing seems like it could be the problem. I will do some research on how to time it. thanks!