I'm new to both the post and atv's. Not having much luck so far with the atv's. Bought 2 Redcat KMZ 150's back in May and have had to replace the reverse gear boxes in both of them. The worst part is that Redcat's warehouse was in Jefferson,LA and of course it wound up like New Orleans so it took three months to get the parts. Now that I have the parts replaced both four wheelers start and idle fine but when I accelerate the just bog down and die. At first I thought it was something I may have done while replacing the gears but I can turn them freely by hand so now I'm starting to think that it's something in the carbuerators. Like maybe, since the last time I rode them it was 70 deg. outside and now it's 30 deg. But even letting the engine idle for five minutes doesn't seem to help. Do these carbs need to be adjusted for difference in elevation or air density between Missouri and China. Any help or suggestions would be greatly appreciated. I'm about to start making adjustments with a two pound sledge hammer or at least I feel like it. Thanks in advance,Jeff

 

Welcome to the forum 3910, are you still using the same gas from the begining? I would think that the carbs got gummed up from sitting so long. But the first thing i would do is put fresh gas in them, if you havnt already and maybe turn out the air screw 1/4 of a turn. Also are you running the stock spark plug? There have been a few people who had problemslike yours and it turned out to be the plug.

 

Thanks for the reply. Both atv's were empty when I finally received the parts so they both have a full tank of fresh fuel. Do you, or can someone else tell me which plug I should use to replace the factory one? Thanks.

 

Your welcome, my pleasure. I use a NGK C7HSA in my wifes yamoto 150. I assume they were both running good when you ordered the parts.

 

Yeah, they both ran great until the reverse gear boxes exploded. Also when I got the first one back together the only way I could keep it idleing for more than a few seconds was to rock the atv from side to side otherwise it would run for about five seconds then die. Figured this was due to the float getting stuck when I had it standing up on the rear tires. This wasn't the case. Thought maybe the float was out of adjustmet, but I haven't been able to find anyone who could tell me what the proper float adjustment was supposed to be so I pulled the other carb. apart and took some measurements. Not sure how this could change on it's own. Probably has something to do with the problem that I am now experiencing. I will try new/different plugs but if you or anyone else can come up with some other suggestions in the mean time I would sure appreciate it. Jeff

 

i would take both carbs apart and spray them out with carb cleaner. As for the float height, you want the float to be level when you hold it upside down with the float bowl cover off. The reason i say to clean the carb is thats what my wifes yamoto needs EVERY time it sits for over 8 weeks, Im not sure why it needs that, but Ive accepted it.

 

Hey 3910 Welcome

Sorry to hear to have 2 Redcat's. Sept 04 my buddy became a dealer and he purchased 4 wheelers and 2 cycles and I am unlucky enough to own 1 of the 150's also. I have not broke the reverse gear but my buddies kid has broken his 3 times and this last time it has been down going on 3 months and still have not got an answer from the distributor in LA when he will have replacement parts.

Mine does not want to start when it is below 60 deg, I live in MN which pretty much makes the machine worthless after Sept. until April. it has spark but does not get gas. I have removed the carb cleaned it and find nothing wrong, the float seems to be at the correct setting. Any ideas? I have never tried starting fluid and really don't want to fearing it will blow the head gasket, and I don't want to know how long the dealer in LA will take to ship me one of those.

I am constantly adjusting the idle setting, if the idle is set too low the machine won't want to stay running at colder temps but if i turn it up once the machine warms up i need to turn it down otherwise it takes off by itself even with the parking brake set.

Most days I wish I would have never came accross this "good" deal!! Fortunately for me my 10 & 8 year old boys understand the machine is a piece of crap and don't bother me 6 times a day anymore to try and get it started.

 

Do these carbs have manual choke? If it idles ok, then bogs down and wants to die, then to me, that's acting like the choke isn't working. If you let it really warm up for a while, does it get better? Wonder what carb we are talking about here... does the throttle cable connect on the side to a rotating wheel? or does the throttle cable go in the very top of the carb?

 

These things have an electric choke and the throttle cable is connected to a little wheel on the side. I hope this doesn't come off as a stupid question but do you have the fuel switch set to on or reserve? I had mine on reserve one time and forgot about it and my quad wouldn't run. I also had it to off once and tried to start it. You can take it from there.

Another thing, just before I sold my 150 (I have a 250 now) it sat in my garage for months and the motor was really cold. I put a space heater near it to warm it up. The motor might just be cold and just like MWQ said check the air screw. It takes more than 5 minutes for these things to warm up in 30 degree weather. I know my 250's temp sensor doesn't even tell me its warmed up until about 30 min later.

 

Check the rubber intake. There have been alot of case of them having cracks in them. Cheap rubber. Sounds like the problem to me. Just a thought.