Hydraulic leak

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warmstrong1955
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Re: Hydraulic leak

Post by warmstrong1955 » Thu Jan 06, 2022 3:53 pm

Wow. They don't make 'em like they used to, sad to say. The new one is ugly too, but OK though, if it doesn't leak I suppose. Doesn't look like Donaldson stuff used to, that's for sure.
It appears the new & old are from two different manufacturers, as there are obvious differences in the castings.

The 'check valve', is the 25 psi element bypass valve. It prevents the element from collapsing internally when it becomes plugged up. That's why a gauge is a good idea. Larger Donaldson filter heads have optional indicators, rather than requiring a gauge, which serves the same purpose.
Looks like the plastic cage broke, or the spring partially fell off the cage.

Glad you got that solved!

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Bill Shields
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Re: Hydraulic leak

Post by Bill Shields » Thu Jan 06, 2022 5:54 pm

Pardon my french ..but what a crappy looking sealing surface
Too many things going on to bother listing them.

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warmstrong1955
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Re: Hydraulic leak

Post by warmstrong1955 » Thu Jan 06, 2022 7:27 pm

Here's a pic of a Donaldson HMK05. Note the seal land is shiny. I've used 3 or 4 kazillion of these, and HMK25's, which are a double filter.
That's how seal lands are supposed to look, but too many people are making things on the cheap these days.....sad to say Donaldson is included.
HMK05, P166663.jpg
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Greg_Lewis
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Re: Hydraulic leak

Post by Greg_Lewis » Thu Jan 06, 2022 7:41 pm

A big difference. I'd be tempted to chuck up that replacement and machine the face flat.
Greg Lewis, Prop.
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warmstrong1955
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Re: Hydraulic leak

Post by warmstrong1955 » Fri Jan 07, 2022 10:58 am

Greg_Lewis wrote:
Thu Jan 06, 2022 7:41 pm
A big difference. I'd be tempted to chuck up that replacement and machine the face flat.
That’s what I’d do, not to mention what I have done or had done in similar circumstances.

Prescribed finish for any o-ring sealing surface is 32 RMS. That includes surfaces for square cut o-rings. They missed that day in class. ;) Those filter heads look to be more like 300-400. Ugly.

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Geochurchi
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Re: Hydraulic leak

Post by Geochurchi » Fri Jan 07, 2022 11:15 am

Hi, if this base leaks, how would one go about milling the surface?
If it ain’t broken keep working on it until it is .
Geo 🇺🇸

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Re: Hydraulic leak

Post by Greg_Lewis » Fri Jan 07, 2022 11:51 am

Geochurchi wrote:
Fri Jan 07, 2022 11:15 am
Hi, if this base leaks, how would one go about milling the surface?

Chuck it in a 4-jaw chuck on a lathe, centering it on the diameter of the alleged o-ring surface.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.

Geochurchi
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Re: Hydraulic leak

Post by Geochurchi » Fri Jan 07, 2022 12:02 pm

That’s above our pay grade, first I have to see if this new base leaks , won’t be around for a week or more, if I wanted to check the pressure on this system I assume I could use one of the ports on this base, HP side.
Geo 🇺🇸
If it ain’t broken keep working on it until it is .
Geo 🇺🇸

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warmstrong1955
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Re: Hydraulic leak

Post by warmstrong1955 » Fri Jan 07, 2022 1:49 pm

It could be done with a mill too, if you have one.

Both gauge ports are in the inlet side on that filter head, so pick the one that' suits you best.

Download this: https://www.donaldson.com/content/dam/d ... -Guide.pdf
Pages 16-19 for your filter assy. Everything you want to know, whether you were afraid to ask or not! :)

If the new one is also NPT porting, be sure you use pipe dope on the adapters. The teflon type works best for hydraulics.

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Geochurchi
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Re: Hydraulic leak

Post by Geochurchi » Sat Jan 15, 2022 12:23 pm

Update, after replacing the filter base and new matching filer the leak has finally been resolved.
Thanks for all the input, I am sure I will be back with other issues.
If it ain’t broken keep working on it until it is .
Geo 🇺🇸

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warmstrong1955
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Re: Hydraulic leak

Post by warmstrong1955 » Sat Jan 15, 2022 2:44 pm

Good news! Thanks for letting us know!
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Re: Hydraulic leak

Post by Geochurchi » Thu Jan 20, 2022 9:45 am

Not only was the filter leaking, upon further inspection after we raised the locomotive up there was a couple of loose fittings on the pump.
If it ain’t broken keep working on it until it is .
Geo 🇺🇸

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