LOL, even a blind squirrel can find a nut every now and then.

I had a race engine do that to me once. One of the pipes was red hot and it had a miss. I was like . I checked the valve gear and sure enough; out of spec by a mile. Just like you the adjuster backed off.

Glad you got it going. Let me know how it runs.

 

The quad is running much better now thanks. Its stopped overheating and backfiring. However after a couple of hours playing around with the carb it seems that to get it to both idle and run right, I need to leave the choke pulled up a quarter of the way. Which I suppose is no big problem but I'd rather sort it out if possible.

A bit of info..

Everything inside the carb is standard, I've set the float height per the manual, I've lost count of the amount of times I've cleaned out the carb and the jets. I've made sure the choke is functioning correctly. There are no air leaks, the airfilter is new and has been oiled. Cleaned out gas tank and filter, fresh fuel

Do you think it could simply just need a bigger pilot jet?

I know that the quad had been sat in a field for several years before I bought it so maybe there is still some gunk inside the carb but I've blasted it with carb cleaner and let it soak in solvents numerous times. There's certainly no noticeable blockages.

Well the quad is running good as it is so maybe I should just go out and have some fun on it.

As always, any ideas would be much appreciated. Thanks

 

I guess it could need a bigger pilot jet but not likely. Just buy a bigger one and try it out.

I would guess you still have a plugged up pilot and that is the first place I would go if it came to my shop............but???? who knows.

Just put a bigger one in and give it a try.............they are cheap and it will settle once and for all if its a dirt issue or a size issue.

 

I finally found out what the problem was, it seems that at some point somebody had overtightened the fuel mixture screw and the tiny point on the end had snapped of and blocked the passage.

It was difficult to tell because at first glance the tiny piece of brass just looked like light passing through the passage.

I managed to get it out and now the quad runs and idles great without the choke.

Thanks for all your help DoctorTurbo. Your sound advice has guided me through all of my doubts with this build and has surely saved me alot of hassle.

 

Well done!!!

I would have never thought of that one, LOL.

One thing you might remember. An old mechanic and very good friend told me this once and its very good advice.

I was blowing out some passages in a carb with air once and he told me not to do that. I asked why not? He said, can you see air? I said no; and he told me thats the reason. You can not confirm the passage is clean or clear with air.

His point was if you use carb cleaner and spray it in one passage it should come out another passage somewhere and you can see it come out with your eyes.

You've done a great job with this rebuild and saved a ton of money. Now it's time to go have fun and ride!!!

If your ever in my area, stop on by and you can wrench on one of my new turbo engines. Going to see what it will do next weekend if things work out!!!

 

If you ever find yourself wondering about valve clearances again, just a littly modeling clay on top of the piston, stick the head on and roll the engine over. The you can pull the head and hopefully measure how much clay was able to fit betweent the valves and the piston. This way you can make a educated guess on if the combination will be ok
Ken

 

Sorry to hijack the thread, but how did you go about adjusting the cam chain tensioner? I can't find anything online about how to do it properly.