Hello all,

I fired up my Kioritz 22cc engine last night and was very disappointed. It had no top end. It seemed it was running in low gear. I was using a Carb that is optimum size for my homies and a tried props from 17 x 6 to 15 x 6. It just wouldn't come up and run hard! I tweaked the needles to no avail.....any ideas. The carb butterfly was opening completely....it just seemed to be asleep. It made a kind of fluttering noise when it was opened all the way up. Is it possible that it is designed to run this slowly. It came off a Mantis tiller and I feel it ran many more RPM on the tiller.

I have a hard time believing this little gem will not run better than this.

As a note, all internals look like new!

Please help,
Tom

Well I am no expert but check your timing it may be retarded and if that is not it your rings might be broken or broken wrest pin or piston or are you runiing the motor in the wrong direction some of those Kioritz have a dual shaft could it be that you are using the wrong end.
There is a whole list of things that could be wrong.

a G23 with a 3/8 bore Walbro (WA125) or an FPE 1.3 will turn an 18-6 prop about 7200, the Kioritz should do as well or better...Check the timing and muffler, a restricted muffler really slows these little engines down...

Tom,,, How did you resolve the RPM problem ?? How much did you finally get out of it ?

A two stroke runs very poorly if it has poor crankcase compression. Make sure the shaft seals are good and that there are no leaky joints.

Tom, something just isn't right. Timing, fuel mixture, something. My Kioritz 23.6cc turns an APC 16 x 8 prop 7900+ rpm's here at 4500 ft. and 90 degrees, with a measured thrust of over 10.5 lbs. It will turn the same prop around 8400 or more at sea level. I don't remember if you mentioned opening the exhaust up, but take out any/all baffles, and install two 7/16" or larger outlet tubes. My older 23.6cc is the best of the small Kioritz models, and I have modified it so don't expect to see quite the numbers I got, but you should still get very decent power out of yours. I think a 15 x 8 APC prop will probably end up being the optimum for you, and you should DEFINITELY see 7000ish if not more with that prop. I once cobbled together a 21cc Kioritz made out of a 16cc crankcase and a larger cylinder I had lying around. With nothing more than a larger carb and an opened up muffler I got 7000 plus on the 15 x 8 APC prop, here at my high density altitude. Keep after it, and good luck.

AV8TOR

Here is what I have come up with. I compared an identical Kioritz that came off a weedwhacker to the one I am trying to run from a Mantis tiller. The timings of the two vary quite a bit. It appears that the engine for the tiller is designed to run with a slow, torque disposition. I will try the engine from the weedwhacker and I bet you 10 bucks that it will scream with the same carb and exhaust system as the one I am having trouble with now.

Now, If the timing is retarded on the tiller engine, will this give more torque at a slower RPM? If so, I think the case is just about solved. It seems to me to be all in the timing!

Tom

Nope..timing should be 28 BTDC..Retaded timing will not get you more torque...

It's possible the port timing and/or sizing is different on the two motors.

AV8TOR

Still low RPM's or did you get it to start to perform better ??????

I had similar trouble with this engine, mine came off a MacCulloch weedeater, but the "experts" here seemed to think it was a Kioritz 21 or 22 cc. My flywheel has TWO keyslots, so the timing can be adjusted several degrees just be using the other slot. I tried 4 or 5 different carbs, from size 18/64ths, 20 and 24/64ths, same results. I even purposley ran it the other direction (thinking I had it going backwards before) It was much worse. So I am convinced it's not the carb, the compression is decent (I've seen much worse) so I am thinking it's the crankcase pressure. I made a new crankcase gasket, and the material I used was much thicker than the factory gasket, therefore increasing the volume in the crankcase, and lowering the pressure, but would such a small amount make such a difference in it's performance? I have 2 more of these engines, complete, but since I've been working on the Honda, this one is on the back burner. The only drawback is that I bought the prop hub, muffler and mount from wackerengines, and I feel I wasted my money. Anyone want to buy all 3 of these engines for the price of the conversion parts? You may have seen pics before, I spent a lot of time grinding and sandblasting the "good" one, the other two are still untouched, one with ball bearings, two with roller.

I have basically put the tiller engine on hold because of some things I found when I compared it to the Kioritz weed whacker engine. The flywheel has three mags on the whacker and two on the tiller. They are also in a different location and it has a different method of keeping the flywheel in the correct position in relation to the timing. The rest of the engine components appear to be identical. I will convert and run the whacker engine soon and check the difference.

I sure hope it runs well....these are cool little engines.

Just a thought.....the First Place Engines 1.3 looks EXACTLY like the engines I am working with - with one exception. They are using electronic ignition. If the whacker engine runs well, I may have to go against my "cheap is better" conversion theory and buy an electronic ignition for the tiller engine.

Tom