Slick Mags

Fortunately I have my own airstrip and hangar and know an AI/mechanic I can work with so I can totally maintain and rebuild my plane. And farm boy and engineer helps too.
 
Snowmass said:
The nail in the mag shaft hole IS for internal timing.
Click to expand...

Nope. The pin is to index the mag at the #1 cylinder firing position. Internal timing has to do with the position of the rotor at the point the points open. It sets the E-gap, which has to be done accurately or the spark is weak. Some guys use a feeler gauge and set the points at .010" or whatever, but for the proper setting the special tool is inserted into the rotor's applicable slot (L or R) and the rotor turned so the tool is against the iron core, and the points are set to open right at that spot.
This is the tool:

12-00302.jpg


Perhaps your old mags use a nail in some other place other than the distributor. They're old enough to be different than what Slick has been doing the last 40 years.

A short video of the technique:

The check of the points gap after setting is to ensure that the plastic cam isn't worn.
 
The nail is absolutely for setting the internal timing. My plane is a 1964 c-210D and I have been doing ALL the maintenance since I bought it in 1971. I think I would know my mags better than you, right?
 
Snowmass said:
The nail is absolutely for setting the internal timing. My plane is a 1964 c-210D and I have been doing ALL the maintenance since I bought it in 1971. I think I would know my mags better than you, right?
Click to expand...

What manual are you using to service your mags? Does it specify a nail or the correct tool?
 
A Slick manual,obviously, Doc. Come down to 03AZ and I will show you the 6 penny nail. No airport insurance so don't fly down. You self appointed authorities are tedious.
 

Attachments

  • Slick timing.jpg
    Slick timing.jpg
    105.4 KB · Views: 36
I wouldn’t mess with them until they come due again. You can buy overhauled mags from Spruce for basically the same price as having them overhauled somewhere else.

off topic but add me to the list of Bendix preferred user.
 
Snowmass said:
The nail in the mag shaft hole IS for internal timing.

...
Click to expand...

No it's not.

Snowmass said:
The nail is absolutely for setting the internal timing...I think I would know my mags better than you, right?
Click to expand...

It wouldn't seem like you do.
Try again.

Snowmass said:
A Slick manual,obviously, Doc. Come down to 03AZ and I will show you the 6 penny nail. No airport insurance so don't fly down. You self appointed authorities are tedious.
Click to expand...

I rarely use the ignore feature on this site, but this was an easy decision. Bye bye.
 
Last edited:
Snowmass said:
A Slick manual,obviously, Doc. Come down to 03AZ and I will show you the 6 penny nail. No airport insurance so don't fly down. You self appointed authorities are tedious.
Click to expand...

I wasn't self appointed. The FAA granted me an A&P after I tested for it, and the FAA granted me an IA after I tested for it.
 
Didn't mean to cause a ruckus; just have a Slick mag I need to rebuild and don't know how...
 
Last edited:
Dan Thomas said:
Perhaps your old mags use a nail in some other place other than the distributor. They're old enough to be different than what Slick has been doing the last 40 years.
Click to expand...

:yeahthat:

Snowmass said:
The nail is absolutely for setting the internal timing. My plane is a 1964 c-210D and I have been doing ALL the maintenance since I bought it in 1971. I think I would know my mags better than you, right?
Click to expand...
No doubt you do. But his mags may be different from yours.

The more recent Slick 4300 series mags use the tool Dan showed to set the e-gap and the timing pin (or nail) is only used to initially time the magneto to the engine. I rebuilt the [single] Slick magneto on an experimental I owned some years ago. It's not rocket science; I set the e-gap using a homemade version of Dan's tool.

Here is the 4300/6300 series overhaul manual.
 

Attachments

Snowmass said:
Did anyone look at the Slick manual page I attached? I clearly shows the nail for timing.
Click to expand...
That's an old, old magneto. Slick hasn't used that sort of internal timing tool for 40 years or more. Those of us that work in aircraft maintenance don't see that sort of thing at all unless someone has mags like that. The only pin we use is the one that indexes the distributor (and the rotor, since the rotor is indexed to the distributor via marked gears) to the engine during installation.

An awful lot of old Slick mags were considered throwaway types. They were a lot of trouble. Modern Slick mags are enough trouble.
 
Dana said:
Here is the 4300/6300 series overhaul manual.
Click to expand...

Thanks for that. Snowmass's old magnetos aren't shown in that manual, reflecting the fact that there will be very few of them still around. That manual originally dates from 1991 and even at that time they weren't included. There were issues with the coil cracking and the impulse latches coming loose. Three ADs on that vintage. I only encountered them once, on an old 172 we hadn't worked on before, and we replaced them rather than fool with them. Shop time and parts cost rules out any repairs on such old stuff. I wouldn't expect any shop to fiddle with my Case mags, either. It took me 15 years or more to find any maintenance info on them.

Those Case tractor mags on my Jodel were certified for aircraft use. There were plenty of them flying around in 1950. Mine dated from about 1946. They still make a real hot spark, hotter than a Slick's, but dealing with 70-year-old components is plenty of fun. There was no built-in way to set E-gap, so one had to set the points with a feeler and then snap the mag over to see what spark length could be produced. Adjusting the points a little either way could increase the spark. The distributor rotor was a flat disc with a molded-in finger, flush with the disc's surface, and the magneto cap had four carbon brushes, once for each lead, that ran on that disc. No spark gap at all. Indexing that to get the timing to the engine correct was fun, too.
 
If posters would be more interested in understanding and less in giving an opinion it would help. In post number 32 I mentioned my Slicks were from 1964. Of course later mags might be timed differently since they are entirely different mags.

Since I am still using them they were not "throwaways" and they have not been much trouble. My main problem is getting parts so I have a collection NOS (new old stock) to keep my mags going. If I lack parts I will probably cannibalize on mag and replace it with one of the new electronic designs. The only failure I had in over 5000 hours was a capacitor and I now carry a spare, along with points, aboard. Actually I have been using this mag type since 1959 on my previous C-175. I have no experience with later Slicks but the those that do were impressed that I could cruise at 23,000' without needing pressurized mags.
 
Doc Holliday said:
I wasn't self appointed. The FAA granted me an A&P after I tested for it, and the FAA granted me an IA after I tested for it.
Click to expand...
A medical doctor here in Arizona has to have passed many tests also but they also can make big (fatal) mistakes. I almost died from a DVT due to the arrogance and ignorance of the head a burn center in Tucson. A mistake is a mistake no matter how many licenses one has. Don't take your FAA certifications too seriously.
 
I am not a shade tree mechanic because I am not a certified mechanic and never claimed to be. But people that hide behind titles are not very impressive. A&Ps and IAs make mistakes all the time. Of course you have never made one.
 
Snowmass said:
I am not a shade tree mechanic because I am not a certified mechanic and never claimed to be. But people that hide behind titles are not very impressive. A&Ps and IAs make mistakes all the time. Of course you have never made one.
Click to expand...

I don't "hide" behind a title. I happen to possess the skills and knowledge to hold an A&P/IA. You have absolutely no idea of the work I've done.

What's not impressive to me is a guy who hasn't the experience nor the knowledge to obtain the ratings.
 
Internal timing of the mag is dirt simple. First, you set the internal timing and e-gap. Then, you set the mag rotor to the correct position to time it to the engine. You can use the “T-118” timing pin, a 6 penny nail or a pop rivet shank. It doesn’t matter. That’s just to set the rough timing on the magneto so that you can find the correct timing with your buzz box once it’s on the engine.

The entire overhaul procedure is dirt simple. The real problem with overhauling Slick mags yourself is that by the time you buy the up to date publication, overhaul kit, and the tools specified by the manufacturer (which you need to do the job) you’ve spent as much as sending 2 mags out to have them done.
 
Last edited:
I have IRANed my 1964 Slicks many times many times and bought no special tools but I did make some. Originally the bearings were unsealed but later there were sealed ones. Unfortunately Slick did not use standard, off the shelf bearings which would have been very cheap and always available. They seem to be very good mags. At least the first models.
 
I believe the first 2 numbers in the serial numbers are the year of manufacture. In your case that looks like 1981. If so no one could fault you for getting a kit with 2 new mags and plugs and a new harness. then you would be golden. there will always be a bendix/slick arguement out there but I think Slicks are fine. They both have coils and coils are like light bulbs in that they are only as good as the last time you tested it. It can fail the next time you use it.
 
Scott MacMoyle said:
I believe the first 2 numbers in the serial numbers are the year of manufacture. In your case that looks like 1981. If so no one could fault you for getting a kit with 2 new mags and plugs and a new harness. then you would be golden. there will always be a bendix/slick arguement out there but I think Slicks are fine. They both have coils and coils are like light bulbs in that they are only as good as the last time you tested it. It can fail the next time you use it.
Click to expand...

The Slick vs. Bendix argument is an ancient one. Bendix mags have many more ADs against them, listed in three different places on the FAA AD website, while Slick only has three ADs total, the most recent being in 1981. But there have been numerous Slick service bulletins dealing with some very serious shortcomings and some of those should have been ADs. Defective points, cams, coil tang alignment, coils, a bunch of QA stuff. I once found both oilite distributor rotor shaft bearings totally shot for no good reason whatever. Cost us a new distributor kit, around $250 at the time, 15 or 20 years ago. Never saw an SB on that. Both mags on a new engine began acting up shortly after the engine was installed, and I found the plastic gears chewing on each other because the small gear hadn't been pushed all the way home on the mag shaft, and its bottom flange was against the distributor gear teeth and making nylon dust that got between the points. Quality control issues every time. Aircraft quality indeed.

It's normally up to the manufacturer to ask the FAA for an AD when reports of defects come in via SDR or other means. If the manufacturer doesn't ask for it, the FAA could do it anyway if the problem appeared serious enough. I suppose there weren't enough forced landings or crashes due to the SB issues.
 
I've had a long standing beef with Slick due to a program they had a long time ago that gave you a substantial discount credit if you gave them your Bendix magneto in exchange which they would then subsequently destroy. I guess I should let it go, they aren't really the same company anymore and the people responsible for that marketing program are probably long gone but the two aircraft I currently own both have Bendix mags on them so I guess I'm suffering from loyalty bias. I always saw the Bendix as a bit better quality, even the p-leads look more like serious aircraft stuff than what Slicks use.

As for the 6 penny nail, yea I remember those but to be fair most people thought you were talking about the distributor lock that's used when installing the mag on the engine. Still, I don't think they had any reason to say you were flat out wrong without knowing the model of your mag.
 
You must log in or register to reply here.
Back
Top