rexbirk

Have had some ignition issues on my MLD-28 engines. They are great motors but I Understand their weak point is the ignitions.

Have an Rcexcell Ignition to install on one of my MLD-28 Engines. The hall sensor mount on this engine is mounted on a raised boss. Since the rcexcell uses an initial timing setting that is far less than the stock one I can't mount the sensor on this boss with two screws. I will have to drill and tap a new screw hole but will only be able to mount the sensor with one screw. . The excell uses 28 degrees but it appears the MLD is somewhere around 39. Also, the rcexcell sensor if mounted on this boss sits up a bit off the prop hub. I would say 1/8 inch. Is that too great a distance from the magnet?

Bottom line is that I can't use the stock location.

Has anyone converted one of these engines to the Rcexcell engine? If so how did you mount the sensor? I saw a video on you tube of one converted. Seemed to run well but could not see the sensor side of the engine.

karolh

My flying buddy after several failed attempts to get his MLD 28 running consistently on two seperate stock ignitions finally switched to using an RC exl ignition which Jody at Valley View installed for him and since then the engine has been running really well.

Karol

captinjohn

There is another way also. Make a ring with the magnet in it. Have it s slip fit over hub and you can adjust the timing with a set screw...see photo. Capt,n

BadAzzMaxx

This has been a problem with MLD engines from the start, The owner of MLD is suppose to be a electronic engineer and can not figure out how to time a engine, The 28cc with the MLD ignition is suppose to be timed at 28 deg. Some will be and others will not. ????

For your question, You have to options.

Option one is to file off the raised section, Drill and tap new threads for screws.

Option two is to remove the prop hub, Remove the key way and install the hub in a location that will let you time the engine, The key is only there for alignment when installing the hub and does not hold it under a load. The taper of the crank and hub does that.

I just always do option one.

Milton

e-fly

Now before delivery MLD-cdi all pass 3-4 hours of aging test above 8 voltage, have photo and video

http://v.youku.com/v_show/id_XMjY4NjYwMzA4.html

karolh

Unless I am missing something in the video all the ignitions are simply connected to a power source and are in a somewhat static mode. Is this test similar to when the ignition is powering an engine while it is running with a load applied.

Karol

jedijody

My Feedback: (1)

Not even close, jumping a .020" gap at regular atmospheric pressures and office place ambient conditions is ridiculously simple and light test for any ignition system. It's a worthless waste of time giving potential users a false sense of security.

e-fly

This is only durable detection in 8 voltage, not a full testing

Planeclothes

My Feedback: (1)

So you would prefer that they put each ignition module on a plane, then run the engine and fly the plane around before they sell it...keep dreaming.

jedijody

My Feedback: (1)

I wouldn't be bragging about testing only 1/2 of the ignition module before sending it out to customers.

karolh

Of course I don't expect that, but just as Jody suggested I think it's all just a waste of time as the ignitions are not under any load.

Karol

captinjohn

The ignition is only as good as the parts you put in the circuit of each ignition. Please do not waste time with air testing....test the quality of each part you use first. Make sure all the electronic parts are good, and then your ignition unit should be good. Capt,n P.S. Also make sure your people can do quality work also.

e-fly

In order to customers can use MLD cdi happy, we are adding various testing project, ensure 100% no fault.

rexbirk

Nice solution Captinjohn. I just wish I was capable of making that!

BadAzz, I like your solution. Never thought of that! Once I did I realized that every Supertigre glow motor I ever had did not use a key. that may be the simple solution.

I still have the concern of the gap between the sensor and magnet of 1/8 inch or so. When using the Rcexcell tester it is working. Not sure about at running rpm though.

e-fly

Thanks your advice, it is quite right

captinjohn

My timing ring idea was a sorta for anyone else that maybe wanted to try something else. Just not using the "key" is the best for your aplication. You may be able to sand or dremal the pickup holder (to makeangle of arm inward) so it puts the sensor tip closer ...same as making the air gap closer. Capt,n

pe reivers

it's what I do too!

BadAzzMaxx

Same here, Have had to do it a few times.

Tired Old Man

My Feedback: (1)

The only thing this test verifies is that circuitry is functioning correctly, meaning that there are no shorts anywhere. As Jody already noted, it doesn't tell squat about how well the ignition functions under a compression load or reflect in any way on the way the engine timing was set up.

The post with the video from e-fly was smoke and mirrors.

mwhar760

My Feedback: (18)

The timing ring idea is what i used when i converted this old 4.2 from the throttle coupled setup that was on it i pulled the hub machined down the old delrin ring tapped 2 set screws at 45 degrees from each other and drilled the 1/8" hole and set the magnet with jb weld!!!! set timing 28 to 30 degrees btdc works flawlessly!!!!!

pe reivers

The di-electrical resistance of air is in direct relationship with pressure. So when in the engine the compression end pressure is 10 bar, the resistance between the spark plug electrodes is ten times as high. That is why an ignition should be tested with at least 1/4" spark plug gap outside the engine. Testing the ignition with the normal plug gap just is for hall sensor and electronics test. It does not provide proof of the ignition delivering the required 15kV HT voltage to the plug tip.

rexbirk

Nice work mwhar.

e-fly

The new sensor shell has been used for MLD engine, makes the MLD CDI better adapt to different gasoline

e-fly

Increase the spark plug gap, continue to aging test...