Checking In!

[Rmendler]

I agree, all kitfox's should have no issue at that altitude or with a 30 degree temperature change.

I think I figured it out, I did try to check the prop pitch but I can't find the instructions for the protractor and I didn't realize until I got to the airport that I did not know what the hell I was doing.

I checked the Jets and the main jet is a #170 and the idle jet is a #55. The Needle Jet was set in position 4, full rich, so I readjusted it to position 3 and we will see how that goes.

I also ordered a #160 Main and a #45 Idle Jet. We will see if that helps raise the EGT's back into the 1,000-1,200 range.

I called the previous owner, the reason for the #170 main jet is the airplane had a GreenSky HACman kit on it! He removed it and THREW IT AWAY because he didn't understand it!!! He neglected to tell me this or put it in the logbooks because he did not feel it would have any effect on flight performance! Now I'm worried if he did anything else to the engine or airframe without logging it.

I'm going to check the prop pitch but I don't feel like it's going to be a problem. It flew fine a few months ago when it was last flown, seemed to climb around 500-700FPM and cruised at 80MPH. I can't it's too far off.

[Av8r_Sed]

Too bad he discarded the HacMan system. Properly installed, it allows fine adjustments of the mixture and EGT's. It's been a great addition to my setup and dramatically helps me keep the EGT's in check when I throttle back.

With the HacMan I'm currently running 190 main jets. I had 205's in there during the winter.

[Rmendler]

I am so confused at this point, another airport bum and I checked my prop pitch and we both got the same result. The prop was set at 18 degrees. I then performed another static check and it produced 6,425 RPM's at full throttle.

I increased the pitch to 19 degrees on the prop thinking it would slow the RPM's down a little, closer to the recommended 6,200 RPMS by GSC. It did the opposite, in fact we hit 6,500 RPM's on the static check this time.

I just got off the phone with tech support at GSC, it is unlikely but it is possible that the blades are stalling (shouldnt happen at 19 degrees according to GSC). He recommended that I try 14 degrees and see what happens so thats the plan tomorrow if I have the time. We are going to set 14 degrees, do a static check and check the EGT's again.

I'm also going to scrounge around some and see if anyone has a prop tach I can use. I don't trust the tach in my airplane now, it could be off which would really screw up these results. We just did not have one handy today.

[Dave S]

Richard,

Good call to to check with the Prop MFG......they are pretty much aware of the possible engine/prop combinations.

FWIW....when I originally set my prop, I got the minimum/maximum pitch settings from the Prop Mfg then set it at a point 1/2 way between the two for a conservative approach. Experience led me to fine tune it...the original setting ended up being within a degree of the optimum setting for the engine/prop/performance.

There is a reason for what you are experiencing, just takes a while to find it sometimes. Changing one thing at a time helps rule specific problems out...

Take care and keep at it...

Dave S

[Rmendler]

Well I'm going to play with the prop, until the new carb jets show up, then I will play with those some. This is the last time I buy anything with a wood prop, it doesn't make good noises when you torque it down. I don't like the sound of wood compressing. Plus it was a PITA to get all 3 blades adjusted just right, took hours! I think IVO has the right idea, make a single adjustment (bolt,key,nut,whatever) that adjust all 3 at the same time

I'm just glad GSC was open on Memorial Day to help me out

[Dave F]

What are you torquing this prop too?

Should be less than 8 ft /pounds or 100 inch pounds.

You are going nuts playing with too many variables.

If you go back and read my post and answer the questions thats would help you alot. Or email me your # and I will call you.

I have thousands and thousands of Kitfox hours alone....... plus many more in rotax engines


Your jets should be 165 and 55 - needles 11G2

Hope this helps -- These engeins are very simple but too many times some try to re-engineer and have no idea what they are doing.

Dave


>>>Check your carb needles - s/b on the 2nd notch from bottom for summer.

Under 5000 ASL this should be a good starting point.
Prop pitch will change your EGT as well.

What is your EGT temps at cruise 5800 to 6000 rpm ?
- what colour are your plugs?
-what # plug is in the engine?

[Dave F]

Well I'm going to play with the prop, until the new carb jets show up, then I will play with those some. This is the last time I buy anything with a wood prop, it doesn't make good noises when you torque it down. I don't like the sound of wood compressing. Plus it was a PITA to get all 3 blades adjusted just right, took hours! I think IVO has the right idea, make a single adjustment (bolt,key,nut,whatever) that adjust all 3 at the same time

I'm just glad GSC was open on Memorial Day to help me out

YOu might be doing this wrong...........

GSC prop re- pitch 10 minutes or so..........

DO NOT OVER TIGHTEN !! REPEAT again........... They are not that supposed to be too tight.

I don't like the sound of wood compressing. Plus it was a PITA to get all 3 blades adjusted just right, took hours

[Av8r3400]

What kind of tach are you running?

An analog tach should not be trusted on a 582. I have personally seen several cases where they were off by 500-1000 rpm!

[Dave F]

What kind of tach are you running?

An analog tach should not be trusted on a 582. I have personally seen several cases where they were off by 500-1000 rpm!

good point Av8r ..........

Too many un knowns -----

[Rmendler]

Fortunately my local Snap-On truck had an aviation precision prop torque wrench for $300

It's okay he had a used one for $120. None of my torque wrenches would go as low or as high as 100in-lbs. We checked it on the truck before I used it on the prop. I torqued from 5ft-lb up to 8ft-lb. No over-torque occured, although the hub was already a little tight. I did manage to fit a .0012 gauge in it but thats not much of a gap, its really tight.

So anyway, we tried the prop at every degree from 12-23 over the past few days just to see what would happen. I had some free time on my hands. The engine seemed to like 19 degrees the most, static RPM was 6,200 on the button. GSC thought this was very high but I found some others online who use as high as 20 degrees.

We tried to use a prop tach, when I tried to get new batteries for it I could not find them, they are L1147 watch batteries, no one here has them. I may have to order them tonight.

So far that's all I have done, play with the prop pitch. It was a good learning experience.

The Tach is an OEM ROTAX gauge. I really wish I could get the prop tach working tonight, I'd go double check it tomorrow.

Oh and the noise when I was tightening the prop was just the urethane, it made alot of noise, even when I would torque to 50 in lbs.

The main jets are 170, idle jet is a 55 and the Needle Jet is a 11G2 on the 3rd richest setting.

I've managed to get the prop adjustment time down to 30 minutes per adjustment, no way to do it in 10 minutes. You can line them all up perfect but as soon as you add some tension to the bolts they shift slightly, so it takes a few tries in my experience. Perhaps I am being a bit anal but I don't want my propeller blades 1/2 degree off, I get them perfect before I start the engine.