TOC 53 question
 

I bought the Honda Sukhoi package with the TOC-53 from WH in the summer of 2007. Life got in the way and I just recently finished the plane and got it in the air a couple weeks ago. I had run the motor on a test stand for about an hour before installing it on the plane then added the hop up kit before the maiden flight. After six flights, I'm turning just over 6900 rpm max (measured with a Fromeco tach, 6954 was the highest reading yet) with the 22x8 "bunny" prop.

The temperatures have been fluctuating quite a bit in north Florida lately and I suspect I had a lean run yesterday as after a couple minutes in the air, the engine wouldn't take more than about 1/4 throttle. I landed long and taxi'd into the tall grass at the end of the runway and tweaked the left gear and tore up the wheel pants so I couldn't richen the high end and try another flight.

I'm curious as to what kind of rpm others have seen with the 22x8 bunny prop and how much run time it took to get the motor broken in. Also, I used a degree wheel last night to determine that the static timing was approximately 22 degrees before TDC. I had read that it should be set at 30 but even after lengthening the slots in the sensor bracket, the closest I could get to 30 was around 27. Has anyone else experienced this?

Thanks to all,
Rick

RE: TOC 53 question
 

27 degrees is close enough, it should actually be 28 but you won't see any difference and I doubt you can actually be accurate to one degree anyway.

6900 is not too bad, I've seen higher with other props but you are very close to peak HP.

Make sure you are using the muffler with the 1" outlet pipe.

TF

RE: TOC 53 question
 

Thanks for weighing in here Tom. Ignition has been locked down at ~27 degrees, I'll run it up tomorrow and post the peak rpm change, if any. My muffler's outlet pipe has an outside diameter of .986", inside diameter is .899". Would you consider that 1" in 3mm speak?

RE: TOC 53 question
 

Yes, that's the right one. For a short time they sent out engines with muffler that had a 3/4" outlet which did a lot to kill power.

TF

RE: TOC 53 question
 

Good to know I got the right one. Incidentally, peak rpm was down to just below 6800 this morning. I've richened the high speed needle to give me 6500-6600 on the ground. I'm running 32:1 with Penzoil air cooled and am well into my second gallon of fuel. On the two flights this morning, the engine cut out at about the 2 1/2 minute mark (both dead stick landings were uneventful, what a floater!). The low needle is just over 1 1/2 turns out, high is right at 1 1/2. Do you think it still needs more break-in time? This is my first gasser and unfortunately all of our club's gas engine talent has moved away.

RE: TOC 53 question
 

Your engine never needed any break in time, they should be reliable from the first minute of running. Break in will develop the compression some but the engine should not need bench running and in fact most experts think that bench running can do more harm than good.

If it's stopping in flight I'd say be sure it has adequate cooling, that's the main culprit in dead sticks as long as everything mechanical is good.

Also check the pickup line in your tank, running good for 2-3 minutes can be a sign your pickup line is not working properly and you are sucking air after the tank gets down below full.

TF

RE: TOC 53 question
 

Thanks, I'll look into baffling it and trying to redirect some of the airflow from going back into the fuselage. By chance do you know what the part/model number is for the stock walbro carburetor? All I can find on the carb is WT 414A, but the closest I have been able to find online is WT-414-1.

RE: TOC 53 question
 

I found a gasket/diaphragm set to fit the Walbro on my TOC-53 at a local John Deere dealer. It's an Oregon brand aftermarket replacement kit for Walbro p/n D20WAT that cost $7.50. The package had a number of parts that weren't applicable, but had what I needed. Baffling is currently in progress, hope to get a few (successful) flights in this weekend. :D

RE: TOC 53 question
 

Hey TOC-53 people.

I found a supplier for mufflers (identical to factory) for the TOC-53 and I now have some spares available.

$50.00

TF