Particle Counts: Magnefine on Power Steering

[Jim Allen]

Since nobody commented on this info in another post (sniff!), I figured I'd post them here in a separate spot because they could be useful. Note that the systems had a full or partial oil change before the Magnefines were added to the return lines on both trucks, so the "before" numbers reflect that. In the case of the '86 truck, I have only done partial changes every 30K, so the oil was still dark. Also note that I tried not to drain any more fluid than could be helped during the filter installation process. By pinching the hoses closed, that was pretty easy, but I did have to add a small amount of new fluid in both cases.

Also note that these were "real" (optical) particle counts done by Oilcheck, not a pore blockage contaminant analysis.

Samples were taken via suction gun, oil hot and engine running.

Truck 1: 1986 F-250 137K miles (about 3K on a partial fluid change, fluid still dark)
ISO Code Before: 21/18/14
4-6um- 1,006,050/100ml
6-14um-160,340/100ml
14-21um- 5,539/100ml
21-38um- 2,616/100ml
38-70um- 154/100ml
>70 um- 0

After 289 Miles w/Magnefine filter
ISO Code After: 18/16/13
4-6um- 159,870/100ml
6-14um-50,720/100ml
14-21um- 3,385/100ml
21-38um- 1,231/100ml
38-70um- 154/100ml
>70um- 0

Note the reduction in the small particles. Considering the Magnefine is a 35um (absolute) filter, all that small stuff must be ferrous and is being intercepted by the magnet. Note also that this was only 289 miles!


Truck 2: 2005 F-150 16K miles (full fluid change/flush 5K previous to test)
ISO Code Before: 20/17/12
4-6um- 545,820/100ml
6-14um-107,520/100ml
14-21um- 2,001/100ml
21-38um- 154/100ml
38-70um- 0/100ml
>70um- 0

After 552 miles w/Magnefine
ISO Code: 17/15/12
4-6um- 68,110/100ml
6-14um-22,320/100ml
14-21um- 1,365/100ml
21-38um- 546/100ml
38-70um- 137/100ml
>70um- 0

Basically the same notation as above. I wonder about having the large size particles in the after sample and none in the before. Sampling error, or is the unit still "making" debris. Likely a little of both.

 

[unDummy]

Too simple of an install not to use on every power steering system in the world.

Great data. Its a relatively inexpensive upgrade that should extend the life of the PS system.

 

[Gary Allan]

Thanks for bringing this data to the filters forum, Jim.

Quote:
I wonder about having the large size particles in the after sample and none in the before. Sampling error, or is the unit still "making" debris. Likely a little of both.


They're shedding all the time. How much depends mainly on the operational variable. Lots of shifting, more shedding. For more stable units (low shifting per mile), you're reduced to material decay due to heat or just plain impurities/imperfections/aging. On something like a dedicated highway car .. you could probably do an initial clean up with a bypass filter and remove the thing after a bit.

In the case of power steering, I suspect the same general rule would apply.

I also agree with unDummy. It's cheap to put a Magnefine anywhere. I will also concede that, outside of a known design/fatigue characteristic, most last a very long time in normal service ....but for $20 and 5 minutes of time?? Sure.

 

[big61fourby]

Yep, good info. Maybe picked up some dirt while sampling? All the smaller sizes dropped pretty consistently. Gary's comment seems legit, but it seems like the filter would catch all the big stuff, even though it keeps making debris...

 

[Gary Allan]

The larger particles could be from the debris on the bottom of the pan. They would probably be of that size. I would think it would be required for them to sink out in the low velocity environment. Those are in the visible range.

..but for all we know it's a typo from the lab. Having that number match is pretty odd.

 

[Jim Allen]

Typically the particles larger than the micron rating of the filter disappear first and fast. It could be that the "snapshots" were taken as the system was flushing larger particles that happened to be in the reservoir, when I sampled i.e. pure chance. The '05 has a remote reservoir and I wonder how much the oil swirls around in there before going to the pump. The '86 has a reservoir integral with the pump, so I guess that wouldn't apply. Well, my plan is to retest at some point down the road after several thousand more miles.

BTW, with "154" coming up so many times, I bought a lottery ticket with that number on it ( ;< )! YNK!

 

[Gary Allan]

Yeah, you would think that they would go out of the picture very soon.

Good call on the lottery number. You could be on to some neo-numerology