stevenchao

The OEM CDI draws 200mah/hr to 230mah/hr => 1,000 mah will last approx 4hr 20min to 5 hr.

autoglide

Thanks Steve, see you at Toledo.

jamesrxx951

i have my mld 28 mounted on my aeroworks yak and looks really good. it's only 25 degrees today but i thought i would get a head start on breaking it in. only around 30oz of fuel through it and getting what i would think are good numbers. idles pretty good around 1500-1600 rpm and had a peak rpm just over 8000 with a xoar 18/6. and producing 16-17 lbs of thrust. running sthil oil at 32:1 and im sure with more breakin and synthetic oil the numbers will get even better.

Jimeni

I'll post results when I get mine. I'll start with stock. Then try different carbs, props, and pitts muffler. Sounds like stock is ok though. I think the Vess 18x6 will be totally unbeatable on it. You will get more RPM's and faster spool up than with Xoar. No cavitiation at all in hovers either. I cant wait to put the MLD 28 on my AW 120 Yak. The SPE 26 is great, and this can only be better.

On the breaking in, you will see a difference every weekend out for a while. The engine will just about tell you when its time to start leaning her out. Gas is definately the way to go on the 120 size airplane with these new lighter little gas engines.

jamesrxx951

you know some people say not to install a gas motor in these planes to heavy and will shake em to death. to be honest the weight is almost the same as a large 4stroke with motor mounts. and really i think the vibration is not as bad as a glow 4stroke. the vibration seems to be a higher frequency and less intense unlike a glow thats just a heavy shake. i am eager to get it broken in and ring her out. i am going to start imac this year and give it a try, i will use this plane as a back up incase something happens to my 50cc that im still putting together. it should be a exciting summer i hope. fuel cost should be next to nothing with running gas too.

skip1320

What is your AUW,looks great!

jamesrxx951

as of now it's 10lbs7oz on a digi fish scale. thats with 2 nimh batteries one for reciever and igniton. which was just about the same as my saito 150 set up but the take off weight should be less because i will use less fuel and am using a smaller fuel tank. i am going to switch over to a123 batteries 1100,and im going to put a scope on the ignition and check for any bad voltage backfeeding into the battery and if it's ok i will use one battery for the whole plane and should drop about 6oz. plus i will try a lightened spinner.

regets ama

My Feedback: (4)

Particular to Steven Chao,

thanks for the info on the MLD 28. based on the readings i replaced my spe 26 with an MLD 28 for my Cermark Edge. it has noticeable performance over the spe 26, i highly recommend the swap for 25% flyers.

the dilemma,
both engines utilize the same spark plug; however, when you visit a local parts store you will find the Champion, rdj8j, has been changed to a new part number. the replacement plug is of exact design/heat range/thread/depth. it has a "tapered" seat for sealing against the cylinder. when you remove the original plug you will find it is a tapered seat that has been machined to accept a washer (not the same type of crush washer that typically comes with a spark plug). fortunately i have a lathe to take the new plug and machine it to accept the original spark plug "washer". i wonder what everyone else is doing for this dilemma.

you can purchase a spark plug with same heat range/thread/depth and gasket but it only comes in the 13/16 plug wrench which of course wont accept the CDI metal boot.

if there is a web site that these plugs can be purchased already machined and include the custom washer please let us know.

jamesrxx951

would that champion spark plug have a cross over number for a ngk plug. i personally like the ngk"s and the one ones for my jetski's do come with the crush washer. just wondering havent checked for myself yet

3dsky

My Feedback: (84)

Try using this web site for plugs,
www.clubplug.net

RDJ7Y 872

This is who i got my MLD/SPE plugs

Jimeni

James, NGK's replacement plug is BPMR6F. Also the champion new RDJ7Y is what I'm using. No issues what so ever, or modification required. Its the same as the original. Seals just fine.

jship

My Feedback: (4)

The MDL 28 cc sure fit nice in My new Sig Four Star 120. Looking forward to seeing how it will fly it.
john

lospeed

Whats the trick to pulling the metal boot off the spark plug?

jamesrxx951

just pull gently and with a slight twist. they are hard to get off but they do. the suck thing is if the sparkplug is not attached then it becomes fun.[>:] there is a metal retainer clip that you have to overcome.

BarracudaHockey

My Feedback: (11)

Make sure the plug boot can't float on the plug, I stuck a tie wrap at end of it, the clip would keep it from coming off without pulling it but it would still float up and down several MM, that will ruin the boot and burn up the ignition module.

jship

My Feedback: (4)

Mine floats up and down about 1/4".

jamesrxx951

i would think that wouldnt matter all that much, as long as the grounded out side of the boot is tight around the base of the plug and it is snapped in all the way then you know that the connection at the top of the plug is on. theres no rubber inside if i remember correctly just a plastic insert maybe. it's not like a car ignition boot were it is rubber and hold completly still. mine slide alittle to and works just fine. what you want is a good connection at the plug tip and base or your spark intensity will be located at the highest resistance

BarracudaHockey

My Feedback: (11)

Trust me, you want to make sure that it stays put.

jship

My Feedback: (4)

Can You show a picture of how You fixed Yours?
john

jamesrxx951

is yours still tight on the sparkplug or does it come off easily like BarracudaHockey's? if its still tight or moves just alittle you are ok.

BarracudaHockey

My Feedback: (11)

I will post a link to the review when it comes out but all I did was stick a tie wrap around the base of the plug boot nearest the cylinder head.

Jimeni

You will hear the distinct snap when the clip goes on the top of the plug. When you release, it will slip back out alittle, very little, that is normal. If you dont have it on all the way, it will move alot, and as stated, when it starts arcing from the clip to the plug, your CDI will be short lived. This is a picture of an SPE 26, but its the same deal. Aproperly installed boot looks like this. You should not need a ty wrap, but it couldnt hurt.

leepord geko

Hey guys,

Just thought i might drop in with already having said this in other forms but, here it goes again I also have my mld 28 in a aw yak 54 and it is awesome! It has about one hour run through it and is pulling a 17x6 at 8600 which is a bit much so i proped it up with a 18x8. Haven't yet tested it with the new xoar but will some time, and dependent on where you live its probably going to be amazing perfomance anywhere because i live at about 2300ft alt and this thing in -10 degrees Celsius pulled it for days with that little xoar. For tech info it weighted in at around 10.5lbs and would hover at 4 clicks under half throttle right off the first couple of runs also using 32:1 amzoil sabre! If your sitting on the fence get off it and go buy yourself a mld 28cc! The engine was a bit hard to get started the first day lol 40 minutes but it was probably because it was -10 outside. Caution the needles needed a lot of adjusting on mine at first it was running like a saito lol, wait i thought this was 2 stroke!

And yes jimeni im getting that Vess prop!

pictures are also in the main aw yak 54 90-1.20 form

Later

stevenchao

Please make certain that the plug tip comes in complete contact to that of the metal clip insert on the inside fo the boot. The boot is hard or nearly impossible to remove without twisting when it is properly in place. This will insure that you will see the max arc in the plug, not between the clip and the plug.

BTW, this was one of the major reason for the early CDI failure. The electrical arc inside the boot destroyed the boot insulation => reduced the CDI effectiveness. Once the insulation in the boot is damaged => it will never be the same...


Peace,
Steven Chao,
CERMARK

Jimeni

Got my 28 today. got it mounted. There are some dimensional differences from the 26. Without shimming, I will now have 1/16" gap between prop and cowl, looks nice, going to try it. I had twice that at least with the 26, same standoffs and spacers. Carb sets a little lower. Stock muffler will hit cowl, I have it trimmed for pitts muffler. Not going to trim cowl until I decide which is best, stock or pitts muffler, just run without for now. The CDI appears to be of much better quality than the one with the 26, especially the lead, and plug boot. Havent even ran it yet, and it has as much compression as my broke in 26. Will run it this weekend, and start collecting numbers.