Return filters contamination

[Stevew66]

I work in the waste field. We run a lot of garbage trucks. We have been seeing a lot of black carbon looking stuff in return filters. We believe it's from the inside of hoses from heat. The engineers are saying it's stuff being ingested through the cylinders. When cutting open hoses we don't see lots if chunking or cracking. It seems the inner lining on bends is thinner on one side than other. Any insight woukd be greatly appreciated.
Thank you

 

[btrueblood]

Any idea what temperature the fluid is reaching, and what is the rated operating temp. for the hoses? Sounds like it might be a good idea to put a temperature data logger on a couple of trucks and find out about the first one.

 

[3DDave]

Anything that big getting past the seals and wipers would mean the fluid should be pouring out. See if the tank filters/screens are still in place.

 

[TugboatEng]

You can send the filters to a lab for testing. It's not particularly expensive. Make sure they test for ATP (biological sources).

 

[LittleInch]

What does that stiff look like if you scrape some off and let it dry on a clem but of paper?

Where is that filter in your system?

Directly off the tank?

Does the fluid still look good?

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