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Old 10-07-2008, 05:37 PM
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Default Used ofna hyper .21 too rich? Help please!

I edited this post to reflect the current situation.....

OK, so I recently got a great deal on a Used T-maxx... In the max is an engine, that on the pullstart says "hyper .21 turbo" and it says hyper .21 on the case.. so i guess its an Ofna hyper 21....

First time I tried it: First thing I did was replace all the fuel lines, then set it to the factory "post break in" settings recommended in the manual.... It actualy fired right up, but as soon as I gave it ANY throttle, it would die instantly.... I quickly determined that it was flooding (based on the large amount of fuel that came out when I changed the glow plug)
So I ended up turning in the low speed needle 2 turns and the high speed needle about 1.5-2 turns to even get it so I could apply throttle and get the clutch to engage... There is still a LOT of fuel at idle and a healthy amount of smoke and even more fuel when its revving comming out of the pipe, and it still didnt get up to more than about 5mph.... It seems I need to lean it more.

Second try: HSN 4.5 turns out the truck will run, but bogs on throttle application, and will barely move 5mph.. HSN 3.5 turns out, the truck moves now, but still not full speed... HSN 3 turns out it seems to run ok, but the tune keeps changing.... I noticed bubbles in the fuel line, so replaced the fuel filter... no more bubbles, but it still wont run good at any more than 2.5-3 turns out, and still spits a lot of fuel out the exhaust at idle....

Today I took off the carb, the original owner had not installed the bolt to hold the carb on, and instead had rigged a piece of stiff wire to keep the carb from spinning.... also the O-ring was in sorry shape.. I replaced it and installed a bolt but I cant help but wonder..... Wouldn'T an air leak cause a lean condition? This engine seems to have a problem being too rich... I'm confused... Going to try it tomorrow to see if the new o-ring helped....

One more thing... In the pinch test, even when the engine seems to be running ok, it will run for about 12 seconds when I pinch it close to the carb... this is with the HSN at 3 turns out....