Still Running Rough! Go Figure!

[Tom G]

Re: Still Running Rough! Go Figure!

Eric/Forrest, thanks for your thoughts. We're going to check out the wiring this weekend and proceed from there. I'll let everyone know the outcome. Thanks again.

[Tom G]

Re: Still Running Rough! Go Figure!

OK, we checked out the wiring and the switch and everything was fine. It still ran up badly so we removed the right mag. The Bendix mags are a tight fit so we were a little nervous that we wouldn't be able to remove it. Last year at the annual when the points were changed the engine was out of the airplane. Anyway it appears that the points were hardly opening at all. Whatever gap they had was almost imperceptable. We're going to clean up the mag, set the points and then keep our fingers crossed that we solved the problem. If it turns out that its still bad I'm going to send them out to Al at Savage Magneto. More at 11.

[astjp2]

Re: Still Running Rough! Go Figure!

If I remember right, the points are set to like .017 gap. That could be your problem. Al does great work, he did 2 sets of mags 3 summers ago for me and a friend. The lead time is a little long but its worth the wait. Tim

[btbell]

Re: Still Running Rough! Go Figure!

If I remember right, the points are set to like .017 gap.

Tim,

I was there when Tom had the mag removed and it appeared like the gap was more like .005. This of course without any way to objectively measure it but the movement was minimal at best. I really hope this is his problem so he can get back to flying his T-craft.

Also, does anyone know if the bolts/nuts that hold the mags on the engine are typically safety wired or stop nutted? I have not looked at mine yet but his is not.

Brian

[astjp2]

Re: Still Running Rough! Go Figure!

I use an internal tooth lock washer, 5/16" if my memory serves me right. Most hardware on the Little Cont's have pal nuts to hold things together. Tim

[crispy critter]

Re: Still Running Rough! Go Figure!

I use an internal tooth lock washer, 5/16" if my memory serves me right. Most hardware on the Little Cont's have pal nuts to hold things together. Tim

I agree with Tim, lock washers is what I have always used.

[astjp2]

Re: Still Running Rough! Go Figure!

It is even the washers that my NEW slick mag kit came with...

[Guest]

Re: Still Running Rough! Go Figure!

Tom,

Be sure to follow the overhaul manual for setting the points.

It probably specifies that the points begin to open when the rotor is in a specific position. The actual measured gap is not the criteria.

I haven't looked at that specific manual in a few years but I am certain it reads like I stated.

I bet you find that your points open too soon.

No, I think I was wrong above, I am changing my guess to "too late"

Stop nuts on the engine should be all metal, don't use an elastic stop nut.

Dave

[Jim Doody]

Re: Still Running Rough! Go Figure!

http://www.sacskyranch.com/egap.htm http://www.sacskyranch.com/timingbendixslick.htm
Dave is correct in regard to point opening. The critical adjustment is WHEN they open. Sac Sky Ranch did my Bendix mags, I highly recommend the quality of their work. A timing protractor and pin is required to correctly time a Bendix mag. Good luck. Jim

[astjp2]

Re: Still Running Rough! Go Figure!

Just let your a&p do it, they should know how or send it to someone that does. It will save you some headaches by letting someone else that has done it before do it. If you have the breadbox mags, send them to AL, its worth the money. Tim

[Tom G]

Re: Still Running Rough! Go Figure!

OK everyone, it looks like we have the problem solved. I had my mechanic set the points correctly and do the timing both internally and externally. The mag was installed and it runs fine. We are going to check the other one as well since it was supposedly set up the same way. I believe that the points were never gapped correctly but ran ok until they started to pit. That's why I want the other one checked since if they were both set the same can that one be far behind in causing problems.

Now that the mag problem is solved my fuel valve under the main tank decided to start leaking! I think that will be a bit easier to deal with.

I want to thank everyone who responded to this thread for their advice. This is a fabulous forum!