MZ202

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ferndog

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Jan 5, 2007
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I have a 503 on my PPC and a 582 on my Slipstream. I would like to replace the 503 but would like to try another engine beside the 582. My friend has a hirth and I won't get one based on his success. Anyone flying the MZ202 or MZ202i Comments?
 

mstull

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Jun 23, 2005
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West Texas
I have 115 hours on my MZ201 so far. It's the same basic engine, but with single carb, and no fan cooling. My biggest complaint/problem was that the engine didn't come with any accomodation for muffler mounting. It took a few tries to find a mounting system that was reliable. The engine doesn't even have holes to mount anything on. The stock muffler is a good balance between light weight, strength, and engine tuning.

This engine gets its power from its large displacement, rather than high RPM. So it tends to vibrate more than some other engines. The MZ202 version does have a lot more flywheel mass, with the starter ring and fan belt drive. So it may vibrate less. I got mine stripped down, with just single ignition and no electric start, so it would be light enough for a legal U/L.

Almost all of MZ's engines share the same 313 cc cylinders. They put different numbers of them in different configurations to make the different engines. I enjoyed working with Leon Masa there. I heard that a lot of people are successfully using MZs in Washington state.

I'm running my engine direct drive, as you can see from my other post here. It's the only 2 stroke I've found that has enough torque to run direct drive.
 

ferndog

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Thanks for the response, doesn't look like many are using this brand of engine. maybe sticking with the 582 or 583 may be the wisest choice. I did read an article about the lack of quality control with the MZ engine, true or not I don't know but I'm not going to be a test pilot!
Bob Fernandez
 

Rockndakota

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Feb 26, 2008
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Leon Massa owner of Compact Radial Engines provided more insight today I thought I should update my post with his comments. His comments are inserted below in "Red"

I got in the last word with my rebuttal posted in "Green" :gig:

The MZ201 engine has a long history. It is an Italian design dating back ~ 12 years. The really big difference between the Hirth and the MZ is how they are made. The Hirth is a cast molding process that uses vibration to remove any air trapped in the pouring process. This type of casting leaves the aluminum more brittle and less dense than other methods. Case in point, it is very common to strip the spark plug threads in the Hirth heads. Talk to owners and you will find many have had to put some form of thread reconstruction to fix the problem.

The MZ201, MZ202, MZ301 are manufactured using a high pressure injection molding process. This makes the crankcase, cylinders and heads more like billet aluminum. Injection molding assures no air introduced during the molding process because only liquefied aluminum is passed into the mold, no vibration is needed. The result is a stronger engine able to transfer heat more efficiently to the cooling fins.

The MZ201 was designed as a free-air engine and worked fine in a tractor configuration, however, cooling proved to be a problem in a pusher setup.
(No, this is incorrect. The 201 only has one carb,it runs at less rpm and produces less hp than the 202,therefore it produces less heat as it is not working as hard, max power is achieved at 4700-5000rpm.It can be used in tractor or pusher config) Thus the introduction of the MZ202. I am unclear who introduced the MZ202 fan cooled engine. However, Leon Massa purchased the manufacturing rights for the engines. His company, Compact Radial Engines, Inc. is located in Surrey, BC Canada. Leon still has the engine's major components molded in Italy. When he receives the components they are then CNC machined to within 2 mil (0.0005" depending on the part and the fit needed) tolerances for final fit. I know of no other company that uses this good of a specification.

The MZ cylinders are
Nikasil, which is a ceramic coating (and nickle) on the cylinder bore. This type of cylinder is much stronger and heat resistant than pressed in steel cylinders. The Nikasil bonded to the aluminum allows the more efficient transfer of heat from the cylinder wall to the cooling fins. Should you have the misfortune of a piston seizure a Nikasil cylinder can better stand up to the overheated piston. With a steel cylinder a piston seizure will, more often than not, require it to be bored to clean up the melted aluminum that fills in the voids in the steel.

When Leon first started marketing the MZ202 in the USA there were some problems. Some were created by Leon
(not likely) (OK Leon, your pride is showing) and some (all) :)roll:) were caused by the end user.

Leon's biggest problem was the final assembly setup that left the factory.
That problem caused most engines to run rough and often times "4 stroking" which is a term used to described a condition similar to running with the choke in the full on setting. It was not an easy problem to overcome for most owners.

The problem itself was simple to correct after discovering that Leon was shipping the MZ202 with the carburetors jetted two full steps below sea level.
(This carb setup was done on purpose and was "setup" by a "Bing" rep right from the Bing factory.The setup was that the carbs were set rich at sea level so that customers could run the engine right out of the box without worrying about "running it to lean", all customers need to "tune" the engine for their own conditions so the factory carb settings were in most cases too rich.We could not possibly setup every engine to suit everybody) A fact that Leon forgot to tell his customers about. (No, It should be obvious that you would have to "tune" the engine to your own conditions and enviorment) (if that is the case, the customer still needs to know the engine is tuned way rich!) His reasoning for the very rich carburetor setting was to assure a problem free engine break in procedure and he never knew at what altitude the engine would be put into service. (more on the break in procedure later)

Several owners and dealers ended up sending their engines back to Compact Radial Engines because the engines would not run good. I was one of those owners. However, rather than sending my engine to him, I loaded it in my car and drove to the factory.

Leon was very accommodating and spent his entire day disassembling, inspecting with a micrometer and caliper and then reassembling the engine. I spent the full day at his side and learned a great deal about the full manufacturing process. I was very impressed indeed.

Each cylinder after final CNC machining and
Nikasil coated is inspected for tolerance and is given one of three classifications (A, B, C). The pistons are also made to match each of these A,B,C, classifications. The result is a cylinder and a piston that match the MZ clearance specification. I will tell you these variances from cylinder to cylinder are very small but one that Leon was concerned about. After all this was to be an engine for aircraft, not land locked vehicles. He knows first hand that a pilot can't just pull over to the side, get out and fix a problem :ermm: (yes, I'm a pilot too (GA and PPG))

My problem was nothing more that an engine with way to rich jet settings throughout the rpm range. Once that was corrected by jetting, re jetting and re jetting again, I got it right. My MZ202 in a pusher configuration does not vary more than 30 degrees F from idle to full power or anything in between. The transfer from each jet's range to the next jet's range is near perfect. And, the MZ202 runs great!

The other problem Leon has seen is poor lubrication.There are a great deal of different 2-cycle oils on the market. According to Leon most are marginal at best. Therefore, Leon has elected to use oversize ball bearings on the crankshaft. Large roller bearings on both ends of the connecting rods to help protect the engine from poor performing 2-cycle oils.

During my visit Leon addressed the oil issue in great detail. He showed me two MZ202 engines that experienced engine failure due to lack of
lubrication.

The first engine was disassembled with the crankcase halves exposed. I could easily see that the connecting rod bearing had been overheated to the point the rod itself turned blue from heat. Interesting thing is the air and oil/fuel mixture enter the engine at the position of the connecting rod bearing on the crankshaft. At this juncture the rod bearing would be the first thing the air oil/fuel mixture would come into contact with. It looked to me as though the owner forgot to mix oil with his fuel.:shock: Don't take bets that the customer ever admitted to doing that, because you would lose.

The second engine failure I saw was due to a rod bearing failure on the piston. This is a crucial area where good
lubrication is a must. Leon let me feel the underside of the piston and it felt like it was rubber coated. He then showed me the wrist pin. It was blue from high heat. Leon stated this area of any 2-cycle engine gets the least amount of lubrication, therefore the oil used must be of the highest quality or failures will occur. Leon then went on to teach me about 2-cycle oils.

I have been a believer of high quality synthetic 2-cycle oils for years. I used them in my racing snowmobiles. anyhow, Leon told me about an environmental requirement in the USA for new oil sold in the USA. All new oil must contain 10% recycled product:speechles Thank you Ralph Nader. Leon said he highly recommends Castrol TTS synthetic oil because it is made in Italy from 100% virgin stock. He then went on to state
lubrication is never an issue with the TTS oil. He has not had an engine failure to date with owners using this oil. That doesn't mean that other high quality oils won't work, he just has a lot of faith in TTS oil.

Leon used my engine to show me another advantage of TTS oil. I had been using Red Line Racing Synthetic 2-cycle oil. Leon took a scraper from his pocket and pushed it across the top of one of my pistons. The crud just pealed off in a soft gob of black. Leon said this was unburned oil and would be the reason de-coking would be needed often. He then showed me a piston and head using TTS oil. There was a complete absence of carbon build up and you could see the jetting of this piston and head had been right on. Would you care to guess what brand of oil I use now? Problem is Castrol TTS oil is hard to find. For more information where to get TTS oil, send me a private email. I am not telling you this just to sell oil.

Final thing - the engine break in procedure is well detailed in the owners manual and full break in takes less than 10 minutes. With this step completed, re-jet the engine using Bing carburetor's jetting charts and go fly.

As far as being a test pilot for the MZ202, that phase has been done. In fact a single place light weight helicopter called the
Mosquito uses the MZ202 as it's only engine option. In this setup the engine is running at full sustained power all of the time it is in flight. Now that is reliability! (yes, and I think I have shipped about 60 MZ202's so far to the Mosquito guys, maybe more I lost count)
(one last comment..... you must run premium or high octane gas to prevent pre-ignition)


Test Pilot, I think not.

Rockndakota
Just telling it like it is
 
Last edited:

rtfm

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Joined
Jan 3, 2008
Messages
3,675
Location
Brisbane, Australia
Hi,
Thank you for this detailed report, and for pointing out some of the more arcane facts about this engine. I have long thought that the MZ range of engines looked good on paper, and your post confirms my suspicion.

BTW, the MZ engines are quite popular in Gyro circles.

Cheers,
Duncan
 

PTAirco

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Joined
Sep 20, 2003
Messages
3,667
Location
Corona CA
Yes, the details were helpful - the MZ201 is the choice for my current single seat project. Hope the price stops increasing past my budget before I finish the airframe though.
 

Rockndakota

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Feb 26, 2008
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Travel full time in an RV
A short update on the MZ202. This past April at Sun-N-Sun I had a chance to observe two versions of the Mosquito helicopter in flight and on the ground. In both cases I was most impressed with the on the ground operating conditions of the MZ202. The engine is started and warmed up like any other 2 cycle engine. After the engines were up to operating temperatures the engines were brought up to operating rpm which is full throttle. Full throttle with no load on the engine. That's right a free running engine with no load against it for more than 5 minutes. Unbelievable, but true! As I watched the two pilots would sit on the ground with no collective applied to the rotor. The engine was running to the point I could hear the reed valves flutter. As soon as a pilot applied a bit of collective to the main rotor the flutter would be gone and the engine purred ever so nice. The engine never changed pitch, such as labor, when lift-off collective was applied. They would fly around the pattern, land and sit there for more than 5 minutes at full throttle with no collective and then do it all over again. I watched this cycle go on and on for over an hour on one of the Mosquito's all of the time running at full throttle. I have never seen a 2 cycle engine run that hard. I asked how many hours were on the two Mosquitoes I saw. One had 42 hours and the other had 45 hours at the start of Sun-N-Fun and had been flying every day during their flying window. I never did get to talk to the second pilot because he was having to much fun flying and had not stopped by the time I left. I would have to estimate the second Mosquito topped 50 hours before the End of Sun-N-Fun.

I thought the MZ202 engine was good but I never expected to see it run at full rated sustained speed with no load applied for such extended periods of time. The MZ202's durability sure proved itself to me.
 

BBerson

Light Plane Philosopher
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A helicopter running at 100% in flat pitch is not exactly no load. The main blades and tail rotor are consuming power because of the parasite or form drag even without any lift. The Mosquito helicopters have a governor to limit the engine from overspeed. Some have a mechanical throttle devise (correlator).

But your right, the engine must be well built to survive in a helicopter.
 

mstull

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Jun 23, 2005
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West Texas
I talked to Leon at CRE. He's sold over 100 of the MZ202s in the last year... mostly to mini-choppers. The engine seems real durable, even run at continuous full throttle for the entire flights. I wouldn't hesitate to get one.
 

GASMAN

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Jun 2, 2008
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EAST COAST CENTRAL FLORIDA
Hi Rockndakota and Mark Stull,
I'm new to the site and was reading your discussion on the MZ202. I own a Mosquito XEL (fuselage version with floats) with 49 hours on it now. The MZ202 is not running full throttle...ever unless the pilot makes a mistake on his throttle control. The engine is run up to around 4500 to 4900 until the pilot is ready to go flying. Once the pilot is ready to fly, the throttle is rolled up to 6000 to 6250 followed by pulling in collective and a little left pedal. As the collective is increased, a mechanical correlator advances the throttle slightly which compensates for the added load on the engine. The RPM is maintained in the 6000 to 6250 range througout flight, until after landing when it is rolled down to a lower RPM/cooldown followed by shutdown.

While 6000 to 6250 is a high RPM, it is not close to "full power". I can be hovering out-of-ground effect (the highest power demand for a helicopter) and if I roll on more throttle, the RPM will climb on up. Likewise, if I pull up on the collective in the same hover scenario, the helicopter will briskly jump up without loading the rotor head/engine.

The MZ202 has loads of power for the Mosquito. It will hover and fly easily at 5500 RPM and lower, but the sweet spot for the rotorhead is in the region of 540 RPM (engine in the region of 6000 to 6250).

Hearing the high engine RPM on the Mosquito can lead one to think the engine is really maxed out...not true. If you listen for a while, you realise the engine is working real comfortable with the Mosquito. That very fact is what convinced me I wanted one the first time I saw one at Oshkosh 2003.

There are other "ultralight helicopters" I followed years back, but didn't like them because they literally were maxed out on power and sounded like they were gonna come apart any moment.

Sorry for the long post, but wanted the readers to realise the Mosquito does not operate at max engine power....the engine has plenty reserve.

Thanks,
Eddy Thompson

p.s I tried to post an avatar, but no size would work. So here I am flying "Mad Mosquito" at an air show. The photo is on my son's gallery on Runryder.

http://www.runryder.com/rrpw.htm?d=/helicopter/gallery/3235/&i=33&a=0&s=-Welcome.txt
 

rtfm

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Jan 3, 2008
Messages
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Location
Brisbane, Australia
G'day gasman,
In another thread, I've documented my project and my search for a decent powerplant. Two contenders have come to the fore: The HKS (60hp 4-stroke) and the Simonini (102hp) My main concern with the 2-stroke powerplants has been a perceived unreliability. I plan a cross Tasman flight as a distant goal, so reliability is paramount in my mind. From what you're saying, the MZ202 (same HP as the HKS) weighs significantly less, produces the same power and is ultra reliable also. Makes one think...

Mmmm

Would you fly across the Tasman Sea in your chopper (longest leg = 6hrs) if you had the range?

Duncan
 

GASMAN

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Jun 2, 2008
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EAST COAST CENTRAL FLORIDA
Duncan,
I didn't make any comments about "ultra reliability", but merely explained that the MZ has plenty of power for the Mosquito and does not need to operate at full power.

Since I have only 49 hrs on the MZ, I don't feel that is enough time to declare a reliability rating yet.

Two strokes (any make or model) are notoriously famous for sudden silence. Risk of flying two strokes is minimized by being ready to handle an engine out. In helicopters it's autorotation. While flying always have a landing site, and be comfortable with doing autorotations to the ground. Then the two stroke isn't so scary to fly.

Looks like you have a very ambitious and potentially dangerous mission planned.
I would not fly any two cycle over water of any great distance. I can land in water in an emergency, but it won't be far from shore. I wouldn't fly over water that distance even in the Buccaneer amphip I just sold, and she never let me down over 10 years flying.

If I were you, I would go with the HKS. Had a chance to fly one once in a Flightstar. Relatively smooth and plenty of power. Quality product with 4 cycle reliability.
My opinion.

Later,
Eddy
 

rtfm

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Messages
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Gasman,
Hi. Thanks for the comments. Whether or not I eventually fly across the Tasman remains to be seen. If my wife has anything to do with it, it'll never happen. But that's an issue for another day. Right now I'm interested in something which will at least have the reliability should I ever want to make the trip.

Thanks again,
Duncan
 

bendixg

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Joined
Mar 14, 2009
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Phil
Leon Massa owner of Compact Radial Engines provided more insight today I thought I should update my post with his comments. His comments are inserted below in "Red"

I got in the last word with my rebuttal posted in "Green" :gig:

The MZ201 engine has a long history. It is an Italian design dating back ~ 12 years. The really big difference between the Hirth and the MZ is how they are made. The Hirth is a cast molding process that uses vibration to remove any air trapped in the pouring process. This type of casting leaves the aluminum more brittle and less dense than other methods. Case in point, it is very common to strip the spark plug threads in the Hirth heads. Talk to owners and you will find many have had to put some form of thread reconstruction to fix the problem.

The MZ201, MZ202, MZ301 are manufactured using a high pressure injection molding process. This makes the crankcase, cylinders and heads more like billet aluminum. Injection molding assures no air introduced during the molding process because only liquefied aluminum is passed into the mold, no vibration is needed. The result is a stronger engine able to transfer heat more efficiently to the cooling fins.

The MZ201 was designed as a free-air engine and worked fine in a tractor configuration, however, cooling proved to be a problem in a pusher setup.
(No, this is incorrect. The 201 only has one carb,it runs at less rpm and produces less hp than the 202,therefore it produces less heat as it is not working as hard, max power is achieved at 4700-5000rpm.It can be used in tractor or pusher config) Thus the introduction of the MZ202. I am unclear who introduced the MZ202 fan cooled engine. However, Leon Massa purchased the manufacturing rights for the engines. His company, Compact Radial Engines, Inc. is located in Surrey, BC Canada. Leon still has the engine's major components molded in Italy. When he receives the components they are then CNC machined to within 2 mil (0.0005" depending on the part and the fit needed) tolerances for final fit. I know of no other company that uses this good of a specification.

The MZ cylinders are
Nikasil, which is a ceramic coating (and nickle) on the cylinder bore. This type of cylinder is much stronger and heat resistant than pressed in steel cylinders. The Nikasil bonded to the aluminum allows the more efficient transfer of heat from the cylinder wall to the cooling fins. Should you have the misfortune of a piston seizure a Nikasil cylinder can better stand up to the overheated piston. With a steel cylinder a piston seizure will, more often than not, require it to be bored to clean up the melted aluminum that fills in the voids in the steel.

When Leon first started marketing the MZ202 in the USA there were some problems. Some were created by Leon
(not likely) (OK Leon, your pride is showing) and some (all) :)roll:) were caused by the end user.

Leon's biggest problem was the final assembly setup that left the factory.
That problem caused most engines to run rough and often times "4 stroking" which is a term used to described a condition similar to running with the choke in the full on setting. It was not an easy problem to overcome for most owners.

The problem itself was simple to correct after discovering that Leon was shipping the MZ202 with the carburetors jetted two full steps below sea level.
(This carb setup was done on purpose and was "setup" by a "Bing" rep right from the Bing factory.The setup was that the carbs were set rich at sea level so that customers could run the engine right out of the box without worrying about "running it to lean", all customers need to "tune" the engine for their own conditions so the factory carb settings were in most cases too rich.We could not possibly setup every engine to suit everybody) A fact that Leon forgot to tell his customers about. (No, It should be obvious that you would have to "tune" the engine to your own conditions and enviorment) (if that is the case, the customer still needs to know the engine is tuned way rich!) His reasoning for the very rich carburetor setting was to assure a problem free engine break in procedure and he never knew at what altitude the engine would be put into service. (more on the break in procedure later)

Several owners and dealers ended up sending their engines back to Compact Radial Engines because the engines would not run good. I was one of those owners. However, rather than sending my engine to him, I loaded it in my car and drove to the factory.

Leon was very accommodating and spent his entire day disassembling, inspecting with a micrometer and caliper and then reassembling the engine. I spent the full day at his side and learned a great deal about the full manufacturing process. I was very impressed indeed.

Each cylinder after final CNC machining and
Nikasil coated is inspected for tolerance and is given one of three classifications (A, B, C). The pistons are also made to match each of these A,B,C, classifications. The result is a cylinder and a piston that match the MZ clearance specification. I will tell you these variances from cylinder to cylinder are very small but one that Leon was concerned about. After all this was to be an engine for aircraft, not land locked vehicles. He knows first hand that a pilot can't just pull over to the side, get out and fix a problem :ermm: (yes, I'm a pilot too (GA and PPG))

My problem was nothing more that an engine with way to rich jet settings throughout the rpm range. Once that was corrected by jetting, re jetting and re jetting again, I got it right. My MZ202 in a pusher configuration does not vary more than 30 degrees F from idle to full power or anything in between. The transfer from each jet's range to the next jet's range is near perfect. And, the MZ202 runs great!

The other problem Leon has seen is poor lubrication.There are a great deal of different 2-cycle oils on the market. According to Leon most are marginal at best. Therefore, Leon has elected to use oversize ball bearings on the crankshaft. Large roller bearings on both ends of the connecting rods to help protect the engine from poor performing 2-cycle oils.

During my visit Leon addressed the oil issue in great detail. He showed me two MZ202 engines that experienced engine failure due to lack of
lubrication.

The first engine was disassembled with the crankcase halves exposed. I could easily see that the connecting rod bearing had been overheated to the point the rod itself turned blue from heat. Interesting thing is the air and oil/fuel mixture enter the engine at the position of the connecting rod bearing on the crankshaft. At this juncture the rod bearing would be the first thing the air oil/fuel mixture would come into contact with. It looked to me as though the owner forgot to mix oil with his fuel.:shock: Don't take bets that the customer ever admitted to doing that, because you would lose.

The second engine failure I saw was due to a rod bearing failure on the piston. This is a crucial area where good
lubrication is a must. Leon let me feel the underside of the piston and it felt like it was rubber coated. He then showed me the wrist pin. It was blue from high heat. Leon stated this area of any 2-cycle engine gets the least amount of lubrication, therefore the oil used must be of the highest quality or failures will occur. Leon then went on to teach me about 2-cycle oils.

I have been a believer of high quality synthetic 2-cycle oils for years. I used them in my racing snowmobiles. anyhow, Leon told me about an environmental requirement in the USA for new oil sold in the USA. All new oil must contain 10% recycled product:speechles Thank you Ralph Nader. Leon said he highly recommends Castrol TTS synthetic oil because it is made in Italy from 100% virgin stock. He then went on to state
lubrication is never an issue with the TTS oil. He has not had an engine failure to date with owners using this oil. That doesn't mean that other high quality oils won't work, he just has a lot of faith in TTS oil.

Leon used my engine to show me another advantage of TTS oil. I had been using Red Line Racing Synthetic 2-cycle oil. Leon took a scraper from his pocket and pushed it across the top of one of my pistons. The crud just pealed off in a soft gob of black. Leon said this was unburned oil and would be the reason de-coking would be needed often. He then showed me a piston and head using TTS oil. There was a complete absence of carbon build up and you could see the jetting of this piston and head had been right on. Would you care to guess what brand of oil I use now? Problem is Castrol TTS oil is hard to find. For more information where to get TTS oil, send me a private email. I am not telling you this just to sell oil.

Final thing - the engine break in procedure is well detailed in the owners manual and full break in takes less than 10 minutes. With this step completed, re-jet the engine using Bing carburetor's jetting charts and go fly.

As far as being a test pilot for the MZ202, that phase has been done. In fact a single place light weight helicopter called the
Mosquito uses the MZ202 as it's only engine option. In this setup the engine is running at full sustained power all of the time it is in flight. Now that is reliability! (yes, and I think I have shipped about 60 MZ202's so far to the Mosquito guys, maybe more I lost count)
(one last comment..... you must run premium or high octane gas to prevent pre-ignition)


Test Pilot, I think not.

Rockndakota
Just telling it like it is
The MZ201, MZ202, MZ301 are manufactured using a high pressure injection molding process. This makes the crankcase, cylinders and heads more like billet aluminum. Injection moldingmolding process because only liquefied aluminum is passed into the mold, no vibration is needed. The result is a stronger engine able to transfer heat more efficiently to the cooling fins??


_________________
Rapid Manufacturing

 

batesjoe

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Joined
Mar 21, 2013
Messages
33
Location
Alamogordo
I am going to jump in the middle of this rather than start a new thread. I have been looking at the MZ202 given it's power and low weight. I spoke on the phone with Leon ad he was very helpful, but afterwards I felt a bit confused/concerned. Perhaps you folks can clear my muddled head.

I am in Alamogordo, NM. The field elev is 4300 and summertime density altitude gets ridiculously high, approaching 10,000ft. To my west is restricted airspace and to my east are the Sacramento Mountains climbing over 11,000 feet in many places.

As I spoke with Leon seeking comfort on high altitude operation and potential for mixture issues, he told me to just set up the carb for my field elevation and fly. OK, on the surface that makes sense, but then as I look at taking trips to places like Tucson, AZ, or Missouri at lower elevations, this takes the problems the other direction.

I don't want to carry a little tackle box of jets and the like with me to change the setup as I have an engine tuned for 4300 feet, fly over 10,000 on my way to Missouri landing at 1,000 feet.

Am I overthinking this, or should I look at a 4-stroke instead?

Finding a quality 50hp 4-stroke under 90 lbs is not exactly easy....unless someone has a recommendation.
 

batesjoe

Active Member
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Mar 21, 2013
Messages
33
Location
Alamogordo
Dana,

Of course, that would be a solution. In my chat with him, I inquired about fuel injection. Nope. Then I asked about altitude compensating carbs. Nope. His solution was as I described. I was hoping that a better configuration would already be available so that I would not end up looking in the aftermarket and experimenting.
 

Dana

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Apr 3, 2007
Messages
10,310
Location
CT, USA
Just because Leon doesn't sell the HAC carbs doesn't mean it won't work. Another option is Jack Hart's mixture control system.

I just carry a few jets in a small plastic box, along with a small Crescent wrench to loosen the bowl drain nut, and a jet wrench. That and a few other items (spare spark plugs, a few other items) are in a small fabric pouch strapped to a frame tube of my plane. It only takes a minute or two to change a jet.

-Dana

Timing has a lot to do with the outcome of a rain dance.
 

N8053H

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Jan 31, 2013
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Right here in front of my computer
These engines " two strokes " go on planes that really are not meant for traveling into different regions with different elevations. As we all know these two strokes are usually on airplanes that are slow and really go nowhere. Its when temps change one must rejet its not usually for elevation change while flying.

I had a MZ 201 and it had an adjustable carb on it. This was a New engine. I also listened to Leon's spill on oils. I believe what he says. But my question is, if this is such a great oil was does Rotax not us it. If anyone knows Rotax you know they put a lot of research into the oil they use. Saying that I used what leon recommended.
 
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