Mag drop rev's

[Bennie Vorster]

Is it very serous if one mag drop 400 rpm and one only 180 and what do I need to check Not the Plugs, done that.

[Junkie]

Change the plug leads and caps yet ?

[Bennie Vorster]

Nop, I ll tackle it over the weekend.

[grubsner]

I have similar problems. I'm not sure about this, but it would seem to have been getting worse.

The RPM on mag 1 drops fast by at least 400 rpm and on Mag 2 there is only a slow 190 rpm drop.

I have changed the plugs 1 hour ago. 582 has 51 hours on the hobbs. Engine runs fine otherwise.

How can I change the plug caps and leads? These are molded to the Mag coils?

I it safe to fly this way...is this an indication of iminent mag failure?

Any ideas?

grubs

[Bennie Vorster]

I have similar problems. I'm not sure about this, but it would seem to have been getting worse.

The RPM on mag 1 drops fast by at least 400 rpm and on Mag 2 there is only a slow 190 rpm drop.

I have changed the plugs 1 hour ago. 582 has 51 hours on the hobbs. Engine runs fine otherwise.

How can I change the plug caps and leads? These are molded to the Mag coils?

I it safe to fly this way...is this an indication of iminent mag failure?

Any ideas?


grubs

Yes take your rev counter and chuck it. Listen to the revs dropping when switching the mags and do not look at the ref counter. If the drop sound similar it is ok. Normaly a Mag is either working or compleatly dead not decresing RPM. The pickup for your rev counter is feeding only from one mag, the reading you get from the other mag is only statick the revcounter is picking up. Am I right or am I right Duck and Morph.

[Duck Rogers]

Am you right or am you right?
I dunno........I just listen for the drop in revs. Not bothered about the amount of rev drop. As long as both work I'm happy :D

[Quentin Ferreira]

Ja jy is reg Bennie

[grubsner]

Thanks for the inputs, but the "listening to the engine" thing is not scientific enough for me!

I need to know what leads to this phenomenon because the other 582's that I have flown didn't have this issue. I can appreaciate that there are many factors to investigate. I agree that as long as both are working, I'm also a happy flyer.

I'll do some troubleshooting in the meantime.

[grubsner]

I have taken the advice and "listen" to the engine when I switch between the two mags and the revs droping sound is similar for both cases. I guess the actual revs indicated is not correct...anyway, most important is that both work!

[Slabfish]

Check your carbs ,if they are not syncronised properly and one opens slightly more than the other,it will cause the same problem

[grubsner]

I have though of that Slabfish but both EGT's run within 10 - 20 deg from each other.

[Duck Rogers]

I have though of that Slabfish but both EGT's run within 10 - 20 deg from each other.

At what rpm? The same rpm as you use when doing mag checks?

[Slabfish]

Still worth checking it,its a very sensitive setting and can be the only logical problem,and it does get un-ballansed over time with wear on the cables ect.

[Bennie Vorster]

I have though of that Slabfish but both EGT's run within 10 - 20 deg from each other.

Just a thought now, DON't pannic. The one mag is conected to the rev counter and the other one is to the charging system of the tryke.

Sometimes you might get the charging mag is not dead but it just do not charge the battery as it should. On closer inspection it sometimes is a WEAK connection or coroded connection to the mag inside or outside of the motor.

What is the changes that sutch a bad connection on either mag might be sensed by the rev counter even befor the circut brakes or you can hear it in the rpm. Go check out http://www.ultralightnews.ca/ducati/index.html


and



http://images.google.co.za/images?svnum ... rch+Images

[Duck Rogers]

The one mag is conected to the rev counter and the other one is to the charging system of the tryke.

Huh?
New way of wiring a system, or what?