Oil Catch Pan for Oil Filter

PhatRV · #1 03-17-2021, 09:42 PM

I found this nifty oil catch device from the SX300 forum. It should catch all the oil dripping as the oil filter is removed and drains the oil overboard. This will work for the nose wheel models but the tail wheel models need some adjustment.

jliltd · #2 03-18-2021, 12:51 AM

I bought one of these compact oil filter drain funnels designed specifically for aircraft filters from fellow VAF'r Steve Melton (rvplasticparts.com) and couldn't be happier. Everybody in the shop is always looking to use it. Our Form-A-Funnel hardly gets used now.

scsmith · #3 03-18-2021, 01:08 AM

My accessory case is my catch pan. The very first step I do for an oil change is that I take a drift punch and put a hole in the top of the oil filter. Then I set up to drain the oil sump, take my oil sample, undo the safety wire on the filter, and go get a soda. I come back a half hour later and the sump is empty, and so is the filter. all the oil in the filter has drained out. I unscrew the filter and put a rag under it, and honest, I spill maybe one drop of oil out of the filter.

I guess this is predicated on having the 90-degree filter mount. If the filter is horizontal, I guess the best you can do is drain half.

rocketbob · #4 03-20-2021, 05:23 PM

Quote:

Originally Posted by scsmith

My accessory case is my catch pan.

Doing this will cause shavings and whatever loose junk is in the filter to work their way back down into the oil pump.

jliltd · #5 03-21-2021, 08:03 AM

Interesting discussion. With a vertical oil filter (90 degree adapter with filter mating surface on the bottom) wouldn't the filter drain down on its own overnight after shutdown? Or is there a built-in check valve or vacuum lock that keeps this from happening? I know the 108/109 filters have an internal bypass valve and the 110 filters do not so could this be a factor in a awl vent hole punch facilitating internal draining of the filter? I used to partner in a Pitts with a 90 degree adapter and it always seemed full of oil and ready to coat the back side of the engine, mount and hangar floor.

If punching a hole in the filter causes filtered debris to return to the sump or oil pump does it come from the outer filter media pleat side or from the center hole of the filter? Looking at this fine diagram from Dan H it appears that the oil pump side oil (pressure) enters the filter through the small circumferential holes around the periphery of the filter and then returns filtered oil to the engine galleries for lubrication via the large threaded center hole:

So what happens when a hole is punched in the top domed area of oil vertical filter to aid draining the filter? Does the oil drain out the center of the filter (filtered) or back around the perimeter pressure side towards the oil cooler/oil pump (unfiltered)? Both? Regardless of scenario do the paper pleats tend to keep a hold on to shavings/dirt by their geometry of folded triangle cross section forming tapered wedges holding the stuff in place? And finally on a properly broke in and maintained engine does any filter backflow make a noticeable difference in engine life? Lycoming list the same TBO without an oil filter using a rock-sized screen as it does with an oil filter trapping fine particuate. I am not advocating either way but personally would err on the conservative belts and suspenders side of using an oil filter and not draining it back internally until some of these questions are answered. Understanding is a huge benefit in aviation.

MacCool · #6 03-21-2021, 08:17 AM

When my A&P was showing me how to change my oil, he used a Form-a-Funnel for managing the oil filter. I was impressed and promptly bought one for both the hangar and my garage at home.

MiserBird · #7 03-21-2021, 08:30 AM

Before I loosen the filter, I place my funnel / drain hose under the base, punch a hole at 12 o'clock near the base, loosen 180*, punch a vent hole at whats now the top. Filter drains pretty quickly from the first hole which is now at 6 o'clock.

I have a Casper 45* adapter, but this method should work on a horizontal filter as well.

PhatRV · #8 03-21-2021, 09:01 AM

Quote:

Originally Posted by MacCool

When my A&P was showing me how to change my oil, he used a Form-a-Funnel for managing the oil filter. I was impressed and promptly bought one for both the hangar and my garage at home.

Interesting tool. Thanks for pointing this out.

wnplt · #9 03-21-2021, 08:01 PM

These work great. Clean with solvent and reuse...

https://www.flyboyaccessories.com/product-p/3401.htm

PaulvS · #10 03-21-2021, 08:52 PM

This plastic tray works well with the Rotax 912 oil filter that is mounted horizontally. The process is to loosen the filter so it can be turned by hand, then hold the tray under the filter while it is fully removed. The oil dribbles into the tray, and when the filter comes off it also goes into the tray. There is very little if any mess.