Mark IV For Sale

117 posts in this topic

Posted

So guys, I know we briefly discussed Rotax 2-strokes. I've done alot of independent research also but I want to hear from the guys who really know the 582 and its innerworkings.

Here's the skinny I'm looking for:

Oil injection systems? Love them? Hate them? Why? Is it easily removed? How do you determine how much oil is actually flowing (40:1, 50:1, 100:1)?

I personally feel that mixing your own gas/oil is better, one less system to fail and less weight. As long as you don't forget

Spark plug changes every 25-50 hours? Best plugs? Gapping?

I've read 25 hours is normal for the spark plug changes.

What should compression be?

Any good fuel additives to keep these things clean? Zmax, Amsoil, Redline?

Anything else to look for? Clean on a regular basis? Oil/Lube?

Are these Bing Altitude Compensating Carbs worth a damn?

I hear they tend to have air leaks, haha

I like the oil injection. As Chris stated, it gives you around 70:1 at an idle, then at WOT its 50:1. I know Joey has been running his using Amsoil at 100:1 with good results, but I am old school and would rather spend money on plugs and oil and use lots of it as it does more than just lube pistons. I like my bearings wet, but thats just me.

I have been getting right around 25 hrs before the plugs need to be changed. I run my oil mixture SLIGHTLY rich just because of the temps I fly and what it can do to EGT's.. again, a little extra oil is alot better than hanging upside down in a tree in the middle of nowhere.

No additives used here. The Citgo oil I have been using burns nice and clean and I have not needed to tear one down yet due to sticking rings. Every 100 hrs or so I use Mercury Power Tune on it and it cleans out all the carbon in the engine! I had one that was getting gunked up pretty bad (was using penzoil air cooled oil) so we ran a can of the power tuned through it. Then we tore it down and could not find one spec of carbon in the engine anywhere!

Spark plugs.. USE NGK 3691 plugs. That is the BR8ES SOLID CAP plugs. I just picked up a set of iriduim plugs I will be trying next week to see how long they last. Gap is .016-.018 but my engine likes it closer to the .016 side. I set them at a tight .016 and they are fine till the next change.

Keep an eye on the RV oil bottle to make sure your water pump seals are holding well (only on the grey head unless it has had the ceramic seal upgrade).

I HATE auto compensating carbs. They SUCK on snowmachines and they suck even worse on airplanes. You can make a mixture control like Chris made and shows directions for, or get the same basic setup from Greensky.

:BC:

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Posted (edited)

Thanks for the answers!

I am now the proud owner of a 1994 Kitfox IV-1200 powered by a 582 Rotax with Injection (100:1 so premixing still necessary).

Flies awesome, climbs awesome and slips like a Banshee. The first flight yesterday was the most fun I have had in awhile.

Funner then my buddies Citabria or his J3. The STOL capabilities with two pilots is actually the best I have flown so far.

We throttled up on the numbers and were way off the ground by the touchdown markers with a slight tailwind.

I got all the logs for everything and they are incredibly comprehensive, nothing has been left out.

The engine is original and has been rebuilt every 300 hours by the manufacturer with no issues.

Edited by RMendler

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Posted

Congrats Richard, official welcome to the Kitfox community. And you got a trailer! :bday:/>

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Posted (edited)

the trailer didnt work out. it was recently modified to fit the new grove gear and matco wheels. as soon as i would hit 35mph the airplane would wag left and right violentely. I tried to go a few miles and couldnt so I took it back to the airport.

I had to go home so I left the airplane at the airport and the owner is going to have the trailer inspected and repaired. He is going to deliver it Saturday for me.

I think when they moved the ramps for the new gear they moved the CG of the trailer too far aft and its causing the wag. It was nerve racking.

I'm also working on a deal for a nice enclosed gooseneck trailer to store it in

Edited by RMendler

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Posted

Well I hope that gets corrected, when it comes to trailers the tail wagging the dog is no fun at all.

P.S. if you think a Kitfox 4-1200 with the 582 is a rocket, wait till you get in an 80 or 100 hp 912 powered one! stirthepot.gif

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Posted (edited)

Well I hope that gets corrected, when it comes to trailers the tail wagging the dog is no fun at all.

P.S. if you think a Kitfox 4-1200 with the 582 is a rocket, wait till you get in an 80 or 100 hp 912 powered one! stirthepot.gif

in the hangar this aircraft was in, there was a beautiful blue and yellow one with a brand new HKS 700E. Beautiful Engine

I may be playing around with different engine options in the future. Definitely interested in the 800 swap if it ever gets done

Edited by RMendler

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Posted

Thanks for the answers!

I am now the proud owner of a 1994 Kitfox IV-1200 powered by a 582 Rotax with Injection (100:1 so premixing still necessary).

Flies awesome, climbs awesome and slips like a Banshee. The first flight yesterday was the most fun I have had in awhile.

Funner then my buddies Citabria or his J3. The STOL capabilities with two pilots is actually the best I have flown so far.

We throttled up on the numbers and were way off the ground by the touchdown markers with a slight tailwind.

I got all the logs for everything and they are incredibly comprehensive, nothing has been left out.

The engine is original and has been rebuilt every 300 hours by the manufacturer with no issues.

Yahoo! Awesome!

Now if only I had a flyable plane.....Two in the shop and Zero in the air is not where I like being, but it is far better than Zero in the shop with no hope of getting in the air! :-)

ChrisB

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Posted

Chris, you just need to spend more time out in the shop with those two planes turning wrenches and whatever else they need!! LOL. One other topic: Congrats on the purchase of the new plane RMendler?? Was wondering what you meant by oil injected but at 100-1 so premixing is still required. Is the oil injection pump set incorrectly? Take care, Jim Chuk

Yahoo! Awesome!

Now if only I had a flyable plane.....Two in the shop and Zero in the air is not where I like being, but it is far better than Zero in the shop with no hope of getting in the air! :-/>)

ChrisB

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Posted

Thanks for the answers!

I am now the proud owner of a 1994 Kitfox IV-1200 powered by a 582 Rotax with Injection (100:1 so premixing still necessary).

Flies awesome, climbs awesome and slips like a Banshee. The first flight yesterday was the most fun I have had in awhile.

Funner then my buddies Citabria or his J3. The STOL capabilities with two pilots is actually the best I have flown so far.

We throttled up on the numbers and were way off the ground by the touchdown markers with a slight tailwind.

I got all the logs for everything and they are incredibly comprehensive, nothing has been left out.

The engine is original and has been rebuilt every 300 hours by the manufacturer with no issues.

Congrats! Now you get to learn the finer points of flying a 2 stroke.. The biggest one I can give you is WHEN THE NOSE IS POINTED DOWN PULL THE POWER BACK! If you let the prop drive the engine, it will lean out, EGT's will go up and you will melt a piston. Let it warm up good!!! I dont go over 2200RPM till I have a solid 140 on the water temp. Cold siezures are not good and can give you a false feeling that all is well because most times, the engine will squeak, then die, then as soon as it cools a tad you can restart and it will seem to run fine. The problem is, there WILL be aluminum off your piston stuck to the side walls and sooner or later, your looking at a major tear down. It is easy to avoid cold seizures... LET IT WARM UP GOOD!

If you running premix with oil injection, then you are either not trusting the pump or it is not set right. If it is oil injection then you should not need to run oil in the gas.... HOWEVER, I have read that some guys have had good results using oil in the gas to keep the tanks from going soft when they are using moonshine for go juice... this may be the reason for him putting oil in the gas.

Dont be afraid to fly the 2 stroke, just remember that you cant drive it like a 4 stroke lycosaurus. The EGT's are you life line, and while they are not 100% accurate on the readings, they will show a trend (for accurate readings you have to figure in the outside temps at the thermocouple to instrument interface yada yada yada.. I like to run mine at 11-1150 just to give me a warm fuzzy that I am not going to melt a piston. I will pay for an extra set of plugs a few times before I want to deal with the cooling fan not turning.

There is ALOT of posts here about flying a 2 stroke and the tricks we have learned to keep them running RELIABLY! ChrisB, Joey, Jim and a host of others including myself have put ALOT of trouble free hours on them. Yeah, I have had a couple ohoh's but that was not due to it being a 2 stroke.. I have had more issues with certified engines than I have with my 582.

:BC:

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Posted

Let it warm up good!!! I dont go over 2200RPM till I have a solid 140 on the water temp. Cold siezures are not good and can give you a false feeling that all is well because most times, the engine will squeak, then die, then as soon as it cools a tad you can restart and it will seem to run fine. The problem is, there WILL be aluminum off your piston stuck to the side walls and sooner or later, your looking at a major tear down. It is easy to avoid cold seizures... LET IT WARM UP GOOD!

Here is what a piston looks like that's had a cold siezure. This came out of my last MK IV after I got it home. The guy didn't have a thermostat in the plane, and he said it was really hard to get it to warm up. It was about +40 F and after taking off and getting to about 200' the 582 died and he was able to land straight ahead with no damage to the plane. It started up soon after and he couldn't find the reason. I should have pulled the exhaust pipe and looked at the cylinders before I bought it, but it ran nice and sounded good so... I figured on tearing it down as soon as I got it home for new seals anyway, but wasn't expecting to put another $700 in parts into it. I'm not crying though, price was low even with the overhaul. Jim

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Posted

Thanks for the info guys. Some serious Drama unfolded this weekend while I was out of town in Atlanta. The airplane came off the trailer while unloading it. The winch strap broke. The tail swung sideways and injured the previous owner of the aircraft. Hopefully the airplane is not damaged.

Then it would not fit in the storage unit I rented, although I was assured the door opening was 10ft-7ft. It was really only 7'8" and 6' so it just will not fit.

It is now outside on the trailer wrapped in a tarp getting pounded by this wicked winter storm we are in. I'm very distraught over everything that has happened and I am going to have a local(ish) A&P go over the entire aircraft and get a conditional done. I'm also going to replace the rubber carburetor intake boots off and replace them with silicone one. I noticed they had some dry rot.

Also, the airplane is not wanting to idle below 3,000 RPMS. In the original owners manual it specifically says "when engine starts, immediately increase RPM's to 3,000".

It will idle at 2,500 but it is very rough and anything below that and it will die (according to previous owner).

What would cause this on the 2-stroke? I personally started the engine and it ran very rough under 3,000 but as soon as it hits 2,950-3,000RPMS it smooths right out. In the air it puurrrrssss

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Posted

would syncing the carbs and possibly installing a Hacman kit help? also, is the GSC prop a descent prop? It's 3-bladed with what looks like a urethane leading edge. I'm not sure how I feel about it.

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Posted (edited)

It will do to get you going. Syncing is always good. The hacman kit may be overkill for now, depending on the altitudes you fly.

Do a search here on the carb boots. Leni and Joey have a source for some awesome aftermarket ones that work great.

Edited by Av8r3400

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Posted (edited)

Sounds like an idle jet might be plugged in one of the carbs. The holes in the idle jet are really small, like I used a small guitar string to poke through them. Pretty easy to get some junk in them. If one carb isn't working right, it will have a hard time idleing properly. The jets are easy to get to, drop the bottom off the carb, unscrew the idle jet. Hacman kit might be nice, but don't do it just to try to fix the idle, the idle circut in these carbs cuts out and the slide/midrange starts to take over somewhere around the 3000 rpm mark. These engines will not idle real smooth at low rpms, mostly from the prop fighting the gearbox at slower rpms, but it should smooth out at 2500 or 2600 rpm. I had a GSC on my Himax for a while, it seemed fine, but I think the factory says to replace them after 5 years..... Not sure how many people do. One thing to add, if you adjust it, you should never have to tighten the bolts down to where the two halves of the hub touch to get the right torque on the bolts. It's junk if you do. Take care, Jim Chuk

PS this is why you (I) should always read the questions better. (like before I hit the reply button!) If the carb boots are leaking air, that would very much affect the idle as well.

would syncing the carbs and possibly installing a Hacman kit help? also, is the GSC prop a descent prop? It's 3-bladed with what looks like a urethane leading edge. I'm not sure how I feel about it.

Edited by Jim Chuk

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Posted

would syncing the carbs and possibly installing a Hacman kit help? also, is the GSC prop a descent prop? It's 3-bladed with what looks like a urethane leading edge. I'm not sure how I feel about it.

It is not uncommon especially with heavy props for the 582 not to want to idle well below 3000. 3000 is a fine RPM to warm the engine up. It is not producing power or heating too rapidly at that power setting.

Balancing the carbs will probably help and is easy to do. You can do it visually or with a manometer. Hopefully you are also a member of the Yahoo site. If not you should join there too. A lot of crossover between the two, but some different stuff too. On that site I posted how I made my own little manometer for nothing, and some instructions how to balance the carbs with it. It does make a difference to balance the carbs.

Back to the idle speed though, my best "advice" is to idle the engine at as low RPM as you can while being high enough RPM for any rattling sounds in the gearbox to disappear. My general experience is that the engine will run smooth at pretty low RPM, even below 2000 with well balanced carbs, but the gearbox will still rattle. Run it where the gearbox rattle disappears and you will be on target. I cringe when I hear 582's idling with the gearbox rattling. I want to run over to the plane and set the idle to where it disappears! :-) (It's just a personal thing) It's an auto reflex for me to idle the engine up where it is running smooth and not worry about what RPM that is at all. On one day/temp/presssure/field elevation and phase of the moon, that might be 3000 RPM. Warm it up at 3000 on that day. On another day at a different airport/elevation/time/pressure and phase of the moon, that might be 2400 RPM. I wouldn't worry about it at all. Just warm it up thoroughly as everyone has said and do the warmup just above the RPM where the engine runs smooth without gearbox rattle. It will serve you well and if I am standing around I won't be cringing :-)

ChrisB

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Posted

I like this forum, thank you for all the info.

My field elevation is 4,700ft MSL. So I'm at a decent altitude, most people don't know the mountains of North Carolina get that high.

I wish this snow storm would let up, I won't be leaving the house for atleast 2 days and I want to go see my new Airplane! I havn't seen it since I bought it.

I was given some brand new, Silicone Injection Molded couplers for the carburetors. These are the same couplers I used to run on a couple race cars I had, good stuff, much better then rubber or a rubber blend. I think that may help out significatly, the factory boots are cracked up some and have dry rot on the edges so I'm sure they are leaking small amounts of air.

I am going to pull the carbs off with my A&P buddy and clean and inspect them, I am also going to clean the K&N filter. I may pull the exhaust to look at the pistons but I have some very detailed rebuild logs for this engine from the same owner so I trust that he ran this engine well.

I'm still thinking of switching to an IFA IVO prop at some point. See if I can't increase the performance slightly. The wood blades are growing on me a little bit though.

I have a long laundry list of mods and improvements. I guess I can start with some vortex generators and the carbs and a good conditional inspection. Oh and of course I want to fly the hell out of it! I'm so excited to get it in the air

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Posted

That thread fell flat.

1) Inquiring minds want to know if the carb cleaning did the trick. Did you get the rough idle worked out?

2). Is the 582 enough power for you? I'm in the same boat, and the price point of a 2 stoke Avid is very appealing. I'm digging deep to find a clean Mark IV.

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