High EGT?

[AVanlent]

I have a Kitfox 2 with a 582 Grey head. 66" GSC prop (not adjustable), with a B gearbox. Ever since i have owned the plane, i have had high exhaust gas temps. I have the carbs set at full rich, and the main jet is 165. My rpm doesn't exceed 6,800, but no matter if I'm at full power or at cruise, my EGT gets up to 12. Also, my plane only flies at 55-65mph indicated. Is this telling me that i am not loading the engine enough and i need a new prop?
Any other information that may be needed i can get! I appreciate the input!

[SkyPirate]

2 blade or 3,..you should get closer to 75-80 pitch should be around 11 to 13 degree's the 582 will have between 4500 and 5000 rpm a "hot spot" I tried to stay out of that range with my 582,...if your getting those temps through out the RPM range it might be your sender or gauge,..what are the CHT readings after it's reached 1200 EGT?

[AVanlent]

I don't have a CHT gauge. So I'm not positive. I only have the water temp and EGT. My prop is a 3 blade, and i believe its fixed at about 9 or 10 degrees. Generally i cruise at 5500-5800 rpm and the EGT doesn't change. If i pitch up, and add some power to load the motor, i can get the EGT down momentarily, but it goes right back up when i level back out

[SkyPirate]

your pitch should be more between 11 and 13,..mine ran around 1050 EGT 350 CHT water temp at 175/180 depending on outside air,..my elevation was 450 at field,..I stayed below 5000,..what is your static RPM ?

[AVanlent]

When i ground tested everything, it ran up to 6500rpm i believe. Water Temp stays well within range.

[SkyPirate]

6500 is about right,.. but your cruise should be higher,..your water temp won't respond quick enough if your EGT's climb rapidly,..even the CHT wouldn't if you had one,,but prolonged higher EGT would raise the CHT,. have you got the EGT on front or rear cylinder? have you got the carb needles set on the same notch front and rear?

[AVanlent]

It has dual EGT probes. Both run the same, all the way up to 12. And the needles are both set full rich in the carbs

[SkyPirate]

if I remember right I was closer to 6200 or 6300 rpm static

[AVanlent]

Does it sound like maybe my prop just isn't right? Maybe if i went to a 3 blade ground adjustable prop it would solve all my problems? I don't know how else to get the performance out of it that i should be getting. My friend has the same plane, except his is on amphibious floats, and his plane flies faster than mine, even with all the drag. The only differences between the planes, other than the floats, is the gear box and prop. He is running a C gear box, and a 68" 3 blade Warp Drive prop. I feel that with mine not having all the drag of the floats, mine should perform much better.

[SkyPirate]

the 2 strokes like I mentioned have "hot spots" in the upper RPM range,..you might have to give more pitch then reset the needles a notch or 2,.. how many hrs on your 582 now?

[AVanlent]

It has 240 hours total time on it. The plane has sat most of its life.

[SkyPirate]

yes you need more pitch in the prop.. a ground adjustable or a prop pitched more between 11 and 13

[Danzer1]

The 1st thing I would check is the gear ratio in your B box - the B was available in a 2, 2.24 and 2.58. If the 582 came out of a different application, you might have an inappropriate ratio to start with for your prop.

How many hours on the engine total? and/or since last overhaul? Any upgrades/mods? All service bulletins done?

I would also check to see if rpm is reading accurately and find a way to read (at least temporarily) egt and cht from each cylinder (you need to be able to compare them) and also be able to read the coinciding coolant temp.

I thought the older 582's were rated for 6400 max. 5 min and 6000 continuous? I'd probably check that too, with Lockwood based on your serial number. They may also be able to tell you who originally bought it and for what application and if it has been overhauled (unless of course you already know the history).

Greg

[SkyPirate]

at 240 she is broke in..if she had sat,..did you decarb the pistons and check the ring groves..one downfall of having the oil/gas mix is the decarb and the rings can get gummed up if its set for awhile,..I used sea foam additive with my 2 cycles,,it helps keep things clean

[AVanlent]

Thanks Greg! its a 2.58 ratio. The total time is 240 hours. And it was built in Ohio, and sold to the guy that i bought it from. But from everything i have redone on the plane, the original builder didn't do a very good job with much! So i wouldn't be surprised if he just threw some stuff on there that wasn't exactly right, such as the prop. Mine and my buddies are the same year, and they both redline at 6800rpm. Which is right where I'm at.

[AVanlent]

I cleaned the carbs, but the guy that i bought it from flew the plane around for a couple years, but stayed close to his home airport in Kentucky. It runs fine, just doesn't have the performance it should, and the egt problem. The fastest it has ever gone since i have had it was 65, and that was with my friend flying it who is a more experienced pilot. Everything to me is pointing to the prop, but i want to make sure before i make the 800-1000$ investment

[SkyPirate]

I have a 3 blade GSC thinking its a 68" that I'm not using..cant remember if it's a left or right at the moment,..believe it or not floats will give you more speed..they have for me added about 5mph to cruise

[Av8r3400]

#1 Question - What kind of tachometer are you using?

Analog tachs are notoriously inaccurate on 582s. Get yourself a tiny-tach (http://www.tinytach.com) to verify you are getting the RPMs you need.

[SkyPirate]

Im willing to bet you put a ground adjustable ot a higher pitched prop on her and maybe some fine tuning once you pitch her up on the carb you can bring your EGT down,,if your buddy is willing..see if he will let you try his prop

[SkyPirate]

mine was 2:58 reduction set at 11.5 pitch for stol my cruise was 75/80 depending solo or pax

[AVanlent]

Thanks! That actually crossed my mind today when i was looking at the 2 planes. Im just not sure if the B gear box can handle the 68" prop, from everything i read, you aren't supposed to put bigger than a 64" prop on a B gearbox, and mine is already at a 66". It seems to do fine, but I'm still new to all of this, and I'm not real positive on how all of these work
And yes, it does have an Analog tach

[AVanlent]

Thanks for all the Info Chase! I was thinking a different prop was the way to go, i was going to go to a ground adjustable speed prop. I don't really need to add anything for take off, i am already off the ground in 300ish feet anyway. So if that goes up on not too worried! I want more performance at cruise than anything! I also figured if i got the right prop and it was adjusted correctly, it really wouldnt hurt my ground roll, if anything, it might improve it.

[SkyPirate]

you get the right prop on her and set the pitch around 11/12 plus minus she will be off the ground shorter then 300' :) my best in my model 2 was 50' landing and 50' take off

[AVanlent]

That would be sweet! I was pretty happy with how fast it got off the ground compared to the Cessna 150! I am still a new pilot, and I'm very novice in the Kitfox, but I'm excited to continue to learn, and really get the plane to its full potential! I definitely do love the plane!

[Danzer1]

Could very well be that a new prop would help get those egt's down. If you can get them down, you really need to get your carbs off of "full rich" as its causing performance problems at the opposite end of the spectrum. To rich can cause fouling and poor engine performance very easily, to very rich and your plugs will eventually foul and it will stop running! You said "set for full rich" - does that mean you have the clip on the needle at the bottom slot?

What size are the jet needle, needle jet and idle jet? The main jet (165 is std. jetting) and that jet only controls the 75% to 100% throttle range. So to adjust the performance below that you need to have the needle jet, jet needle and clip position all correct for your most used density altitude and the air screw then adjusted to get the most efficient spark.

I've done plenty of these and had (not anymore) relied on the previous owner knowing what he was doing and found lots of things screwed up and most times ended up starting with all new parts at factory settings and adjusted from there. I've found jets drilled out and thought they were correct and weren't, causing me unnecessary days of trying to tune a carb that never could due to the unknown changes.

Also on the 2 strokes the fuel level in the bowl also affects rich and lean - if your floats aren't "floating" at the right height, that will also cause problems.

What do the ends of your spark plugs look like - wet or dry? Black, dark brown, light brown, grey, white? you can tell almost everything about how an engine is running by "reading" the plugs.

Also, Skypirates idea of Seafoam is right on - it works wonders. If you've been running full rich, you might have a fair amount of buildup. If in doubt though, pull the exhaust manifold and you can see everything. If it didn't clean up by running with Seafoam, it'll probably need a rebuild.

Greg

[AVanlent]

Thanks Greg! I will check all of that too! It was suggested to me that i may need to lean it back out with the needle valves. The idea of making sure everything is clean too! I will definitely pull the plugs and take at look at what has been going on. Hopefully i find good news and i can fix the problem with minor set backs!

[Danzer1]

Andy,

You may want to do all that before investing in a new prop. The 582 has a history of running hot with the stock needle jet (272) it may work better with a 274 or 276 - but I would want to know what is in there now for a baseline - idle jet size, needle jet size, jet needle size, clip position, main jet (known 165 - if not previously drilled), and how many turns out the air screw is from seated (never overtighten, just turned until it stops).

Also, it sounded a little bit like you were guessing on your prop pitch. Properly read, the pitch degree is measured at 75% of radius - 66" prop = 8.25" in from the tip. I'd verify what you've got so you can use that as a baseline.

Greg

[AVanlent]

That make sense! All of this Carb stuff is new to me. I have never gotten too involved in the carbs. The only way i know what my prop angle is was from putting the protractor on there 3/4 the way to the tip and taking a reading. And the protractor told me 9-10 degrees. Do you think that the carbs needing to be adjusted the way you're talking would affect all around performance? To where they may actually be holding me back at cruise performance as well?

[Danzer1]

Absolutely - yes! You want your carbs running just on the rich side of lean at idle, mid range and 3/4 to WOT. Many different combinations/adjustments/variations to get there.

Before digging into the carbs though. Pull your plugs and look at them. Note which hole they came out of and take 2 pictures of the ends - one from side showing the gap and one from the end down into the electrode well (noted in relation to the cylinder holes) and post here (before cleaning). Clean them, check the gap and reinstall in the same holes. Or better yet, replace them - checking the gap on the new ones - even pre-gapped plugs are many times incorrect.

If it's not bogging down, sputtering or cutting out, it's probably not as rich as you think, but actually could be lean in the mid-range - based on your egts.

Lets see what the plugs say!

Greg