Piece of cotter pin found in oilscreen!?

Emagair now recommends a 5/64" width cotter pin.

1. Does any one know the length required?
2. Is the Slick cotter pin a substitute for the " newly recommended" Emagair cotter pin?

Thanks,
TomH

Thanks for this thread. While I have inspected my PMAG each year per the manual, I have never given the cotter pin a second thought. I decided to pull mine again today to look it over. I found a much smaller cotter pin than currently recommend and it was loose as well. It was all there however and had no signs of letting go any time soon.

Anyway I changed it to the right size which was a pain in the rear! It is almost impossible to get the right size pin in there due to the design of the gear and the fact that the PMAG shaft is drilled a bit off center.

Getting this pin in takes a bit of patience and the right brass tools to prevent damage to the pin and the gear. You also have to be very careful to not damage the PMAG with excessive force to the shaft.

tomhanaway said:

Emagair now recommends a 5/64" width cotter pin.

1. Does any one know the length required?
2. Is the Slick cotter pin a substitute for the " newly recommended" Emagair cotter pin?

Thanks,
TomH

Click to expand...

Sometimes I do what I recommend...

http://www.vansairforce.com/community/showpost.php?p=1092365&postcount=50

This is the Slick cotter pin -



I measured it's width at 0.078 inch, which is the 5/64 previously mentioned.

Thanks Gil,
Just ordered a couple.

....This is the type of incident that makes you wonder if something out there has it in for you? This does happen, and when it does the part that separated usually makes it to the oil reservoir. Generally the big damage takes place when it goes through the oil pump (if it's in the screen it did) starting a cascade of damage, usually resulting in a vary expensive and time consuming complete tear-down. We offer a very simple, easily installed little accessory can save the day for many, by preventing some of these incidents. Here is a link to it; http://antisplataero.com/products/magnetic-super-plug
Thanks, Allan...

PerfTech said:

Generally the big damage takes place when it goes through the oil pump (if it's in the screen it did)......

Click to expand...

No, the sump screen is upstream of the pump. Trash has to get past the screen to enter the pump.

The big damage happens before the cotter key chunk gets to the sump. It is loose in the accessory case.

...I stand corrected! I was thinking automotive type oil pump. Good to know you are watching.

Just checked my dual PMAGS.
Ordered with Aerosport io-375 approximately 2 years ago.
Both PMAGS had the larger 5/64's cotter pin in them.
They fit so tight it would have been a bear to pull out.

Yeah, tried replacing mine with the tight fitting correct size pin yesterday. No luck so far. Hate to ship them back to Texas just to have a 10 cent cotter pin put in but may have to.

Erich

erich weaver said:

Yeah, tried replacing mine with the tight fitting correct size pin yesterday. No luck so far. Hate to ship them back to Texas just to have a 10 cent cotter pin put in but may have to.

Erich

Click to expand...

My suggestion is to use a file to sharpen the ends of the pin. That allows the new pin to better self-guide through the openings.

erich weaver said:

Yeah, tried replacing mine with the tight fitting correct size pin yesterday. No luck so far. Hate to ship them back to Texas just to have a 10 cent cotter pin put in but may have to.

Erich

Click to expand...

Just replaced the original 1/8" pins with 5/64" on 2006 vintage pMags. The ordinal pins looked fine, but replaced them anyway.

The 5/64" pins are a real PITA. After a few trial and error attempts, this process finally worked - but it was still amazingly hard:
- Trim the 5/64" pin to final length before inserting. Note that for his application, the folks at emag want the both pin legs to go around the castle nut, not one leg bent over the top. Reason provided was accessory case clearance.
- Use a file or Dremmel tool to ease the pin ends.
- Verify the castle nut torque and make sure you get the shaft pin hole center of the castle nut fingers. You will need a helper for this step - and a good strap wrench.
- Carefully bend the pin so that you can get it started. Push in until you get to the bend. Ease the bends as you continue to push it in (various tools are needed BUT DO NOT TAP THE PIN IN).
- Once in bend the legs around the castle nut.

I sent a note to Brad at eMag recommending he make a You Tube video of the process - like Dynon does for autopilot servo sheer pin replacement.

Carl

Carl Froehlich said:

- Use a file or Dremmel tool to ease the pin ends.

Click to expand...

I don't understand what this means

Thanks

Erich

erich weaver said:

I don't understand what this means

Thanks

Erich

Click to expand...

Sharpen the ends so they start through the hole(s) easier.

tomhanaway said:

Is the Slick cotter pin a substitute for the " newly recommended" Emagair cotter pin?

Click to expand...

No, doesn't look like it to me. I have received replacement pins from both E-magair and the slick pins from ACS. The slick ones have one leg that is significantly shortened that I dont think is going to be long enough to secure in the castle nut. The ones from E-mag are significantly longer, and will probably require trimming to aid in installation.

erich

Broken Cotter Key

swisseagle said:

YES! Due to all of your comments and inputs, he pulled the mags and found where the missing part belongs to:

Click to expand...

Be VERY careful on how that cotter key is installed into the P-Mag or MAG. As shown, it may come in contact with the case wall behind the ignition. I installed one this way (as shown) and it scratched marks into the case wall, resulting in aluminum particles in the filter. I was told that the cotter key should be wrapped around the hex flats of the nut instead...