What's function of this Filter By-Pass Indicator Assembly?

I have a 1977 Massey Ferguson 30B with a 34A Loader, that I'm rebuilding. The parts book breakdown copy above is of the 10 micron hydraulic return filter assembly for the 34A loader.

The part in question here is #5, called a by-pass indicator assembly, Massey Ferguson part 1096245M91. Above is a large picture of a similar part number P160351 made by Donaldson filter.I found out that 1096245M91 is also made by Donaldson, and is their part number P160353 (but they have no picture of it).

Here's my problem:
For a filter change, the service manual says to remove the By-Pass Indicator Assembly, and replace the O-ring. But, I can't get the part out from inside of the #2 (Filter Head Assembly), the part is jammed. Since I don't see any seal on the by-pass indicator, I assume that it is hidden inside the filter head assembly, in that groove shown in #5.

<big>[b:654c4848f0][u:654c4848f0]Has anyone ever worked with this part before? </big>[/b:654c4848f0][/u:654c4848f0] What is it for? Looking at it, I can't see how it would provide any function other than to hold the filter in place, for without it, the filter can wobble open at the top.

This By-Pass Indicator is stuck, and I'm not going to play with it unless, someone tells me otherwise, for the only way to remove it to install a new seal, looks to be, to break it (it's plastic). The part is still available from MF ($18.50).



I'm now trying to find out exactly how that part works, what is it's function. Is anyone familiar with this part?

The Donaldson P16053 is also a substitute for p/n's:

Cross Reference: ADAMS P160123, ADAMS P160826, AIR SUPPLY COMPANY 122273, ATLAS 353368, BADGER 76102455, BARKO HYDRAULICS INC 55900087, BARKO HYDRAULICS INC 59012, CEDAR RAPIDS 4517550802, EIMCO W5M353368, FRANKLIN O33225, GARDNER DENVER 005432550007, GARDNER DENVER 2109125, GRADALL 90202448, HAWKER SIDDELEY 10033225, HAWKER SIDDELEY 33225, HEIN WERNER 453201, INGERSOLL RAND 125290, INGERSOLL RAND 35260918, INGERSOLL RAND 35290287, INGERSOLL RAND 35296532, INGERSOLL RAND 35301944, INGERSOLL RAND 35327741, INGERSOLL RAND 50815620, JURA FILTRATION P160353, KALMAR 0074856818, KALMAR 4856818, KELTEC K1005, LEROI DIVISION/DRESSER GD2109125, LETOURNEAU 4073184, LOADMASTER 10996, LOADMASTER 23818, MANITOWOC 9437100186, MARINE TRAVELIFT, INC. 1005786, NACCO 266414, P & H 36Z1085, PREMIER EQUIPMENT GR943710086, QUINCY 125656051, RUSTON BUCYRUS 62303769, SANDVIK 69022282, SCHRAMM 50009116, SULLAIR 407103, TEREX 1036Z1085, TEREX 9055365, TROJAN INDUSTRIES 685132600, WALGAHN-MOTORENTECHN 00810893



Here are some more cross references:

http://www.filterspro.com/resu...fm?searchfor=P160353

It was/is used in many applications, so I'm posting this now in the Tractor talk forum.

Is there a window in the upper filter "head" where you could see a change in color if the plastic part moved due to pressure from a plugged filter? (Or a pin or other visual indicator?)

ANYHOW, you say it's still available for $18.50 and a PROBABLY in important part of your hydraulic system. How can you afford NOT to replace it???

re: Is there a window in the upper filter "head" where you could see a change in color if the plastic part moved due to pressure from a plugged filter? (Or a pin or other visual indicator?)
[b:654c4848f0]NO. There is no device to show if the filter is bypassing[/b:654c4848f0]

re: ANYHOW, you say it's still available for $18.50 and a PROBABLY in important part of your hydraulic system. How can you afford NOT to replace it???

I don't know how important it is. To me it just looks like it's to hold the filter, and the one I have stuck is doing that fine.

If I don't find out what it's for, I likely will just break it and get a new piece, however, it takes 1 1/2 hour drive to get the $18.50 piece, and I have to wait one week to get it.

Have 'em MAIL it!

It tells you that you need to change/clean filter. As the filter takes more impurities less fluid can pass causing it to by pass. Is that actually your question?

[b:654c4848f0]re: Is there a window in the upper filter "head" where you could see a change in color if the plastic part moved due to pressure from a plugged filter?[/b:654c4848f0]

I received drawings and explanations from Donaldson Filter (they appear to be the OEM supplier for this part). The filter head indeed has a "a window in the upper filter head where you could see a change in color if the plastic part moved". However, my unit has no window, the port is capped off. The service manual says nothing about the "window", or how to know if the filter is in bypass. [u:654c4848f0]It appears (?)[/u:654c4848f0] that </u> MF didn't use that "window" feature, but does use the bypass plastic piece. Although it is hard to believe that pressure on the filter can compress the spring on my unit. I ordered the By-pass indicator assembly 1096245M91 from MF to compare with the one I have in place now.

Here's description from Donaldson:

Dirty oil comes in the inlet port and is directed to the top of the filter assembly by a internal baffle tube. The oil goes down and thru the element from the inside out. As the element becomes dirty the oil pressure on the inside of the element increases until the spring force is overcome then the entire element starts to shift down along with the bypass valve assembly compressing the spring even more and eventually creating a gap between the bypass valve and the baffle assembly. The dirty oil will now go thru the gap created between the baffle and bypass valve and flow out the outlet port. When this happens the filter is in bypass and no fluid is being filtered.

This is what the filter looks like:

Donaldson definitely is the OE manufacturer of the entire filtering assembly. Their name is right on the head. The filter head indeed has "a window in the upper filter head where you could see a change in color if the plastic part moved". However, my unit has no windows, MF didn't use that "window" feature, but does use the bypass indicator plastic piece.

I ordered the original By-pass indicator assembly 1096245M91 from MF to compare with the one I have in place now. It is the same. The old one was stuck and so, it is likely that the filter (It was 23 years old! Savages!) if it went into bypass, would just pop out from the bypass indicator, instead of the indicator sliding down with the filter (the indicator snaps into the filter).



Here's description from Donaldson:

Dirty oil comes in the inlet port and is directed to the top of the filter assembly by a internal baffle tube. The oil goes down and thru the element from the inside out. As the element becomes dirty the oil pressure on the inside of the element increases until the spring force is overcome then the entire element starts to shift down along with the bypass valve assembly compressing the spring even more and eventually creating a gap between the bypass valve and the baffle assembly. The dirty oil will now go thru the gap created between the baffle and bypass valve and flow out the outlet port. When this happens the filter is in bypass and no fluid is being filtered.