plug for a weedeater xt200

[38racing]

I have my neighbour's xt200 featherlite.Says it runs but then stops and won't restart. I started it and it surged and needed some choke. I'm figuring carb. So I drain fuel and to me it looks like straight gas. So before going further I filled with 40:1. I checked carb screw (single screw type). It was way beyond 1.5 open. I set it at 1.5 and it started right up. To get best rpm I had to turn screw in a bit. Idled and reved good so I started trimming. Short period and it cuts to slower and will idle but not rev up . screw adjustment can't get high rpm any more. I'm thinking fuel starvation so I pulled the filter from tank and checked with carb cleaner. Good flow plus priming send a great flow back to tank. If fuel then internal to carb, maybe screen. Or thinking too a heat an issue. I pulled the plug. RCJ6Y with gap less than 20. I could just regap but figured a new plug. I have 2 pdfs for xt200, one says featherlite, other doesn't. Other says rcj6y and featherlite says rcj8y, slightly hotter. I have off brand for both but ngk bpmr7a that crosses to the 6. I guess I'll go with it for now and gap to the .025 in the manual. any thoughts on why different plugs in the different manuals?

[38racing]

so new gapped plug even cold started I can only get full throttle surging. So pulled carb .zama c1u-w7c. pressure test has it holding at 7+. It popped about 18. Manual gives part number for c1u-w7 ,both repair kit and gasket/d kit. but on one page it says no repair kit for c1u-w7d, must replace carb. Bit confusing. D different from a,b,c? I have a kit supposed to fit the w7. I'll see what fits when I get it apart.
UPDATE: yet I find this right on zama site
http://zamacorp.com/tclist.html?cnum=C1U-W7D
same part numbers for both kits and all of a,b,c,d

[KE4AVB]

Many companies are using this trick to up sell a carburetor lately along with other parts. They depending on the DIYers not knowing how to repair these carburetors. Kohler is one example of larger engines where you you can't get repair kits for the carburetors. Even Walbro has scrubbed the info from their sites.

Stihl is one that does this as they are part owner of Zama and has barred Zama from selling the repair kits via the distributors. Zama is actually scrubbing the information for the Stihl only carburetors. This really pisses me off as I had to change out 12 Zama carbs earlier this simply because they wouldn't sell me the repair kits and couldn't get them from Stihl even though I had the Stihl kit part numbers. Just just comes down to greed. Oh they will say it cost too much to stock the kits. It just those with pencils sharpen both ends figuring out how to stab us in the back so they can make a few pennies more.

Just note many times all you need is a new metering diaphragm and gasket as the diaphragm gets stiff so I usually just buy them in bulk. And maybe a new filter screen as the one you can't see through tends to clog up.

If I can figure out the kit number places like CTS will sell you an after market repair kit if they make one.

[Arkie]

Yep, Zama plus other have started the no kit available thing, but you can USUALLY find a kit if you have a part number, but when flogging one recently I could buy a clone carb and get a tune up kit with spark plug, fuel filter, tygon tubing, air filter, and primer bulb for less than I could get and install a kit. (around $15 with free shipping in USA) I seen a Zama carb cross reference to kit and parts on-line awhile back that was good for getting the correct kit cross reference. The NLA available kit thing for carb kits is going to cause the price of kits to be jacked up soon or not available.

Both of them plugs you mentioned I suspect should allow it to rev up. (the 6 and 8 as I've used both with good results, but I do not trust any Champion small engine sprak plugs, especially the J6 and J8 areas)
I'm little concerned about the straight gas you mentioned. I would probably see if I could get the muffler off to take a peek at the side of the piston before getting any parts or spending any more time. (might be whipping on a dying horse)

I had a Poulan Pole Pruner/trimmer with a Zama that was acting similar to your described issue awhile back also and first found the fuel filter off in the gas tank so I pulled the pump side plate of the little Zama and give it a cleaning, cleaned the filter and installed new fuel line and it took off. Was starving for fuel, idled good but the H jet would not adjust.

I did not have to pull the metering side of the carb due to finding debris on the pump side.
Carb was easy to get off/on in case I needed to go back to the metering side was another reason I did not disturb the metering diaphragm side.

[38racing]

i put the gasket kit in it. screen was clean. pressure tested fine. i set carb. it's the single needle. top rpm abou 8800. i trimmed through almost a tank. i refilled it when he picked it up. he csme back when he had used almost a tank. said it was running fine and then wouldn't rev up. I confirmed and adjusting carb didn't help. I thought the tank had enough fuel but refilled anyway. ran a bit better but top rpm in high 7k . hit 8.2 once. he took it and said would bring back if it failed again. not back yet. I eondeting maybe a hot coil breakdown. I didn't pull muffler since it looks like crankcase cover has to come off to get at muffler. I have identical unit (maybe 2). mihht kit one of those too.