Hydraulic Return Filter - gets no oil

[Redpla]

Just taken out my Dexta's hydraulic return pipe and filter, to check the back-pressure valve.

The image in the Fordson manual (Nov 1957 version, Section 8 Fig 10) shows that the return oil flow is split: some goes into the filter and some (if pressure is high enough) goes through the back-pressure valve.

On mine, the pipe which runs through the filter to the back-pressure valve is solid. No way for the oil to flow into the filter at all.

(1) Should I drill the pipe and if so how big, how many, and whereabouts?
(2) Where can I get replacement filters... they don't seem to be a thing, or I'm searching for the wrong term.

[Billy26F5]

I wouldn't modify the pipe, a pic would be handy. There are replacement filters around, but I would rather clean the original one as they're better quality and it will then be fine for ages.
Sandy

[Redpla]

Thanks Sandy.
I did take some pics, but found I don't have permission to upload. Probably I've not made enough posts yet.
Tried cleaning the old filter - but it's a paper element completely blocked with what looks like emulsion from old watery oil. Did find a supplier with one so on order. But, without any feed from the return-pipe into the inside of the filter, it's hard to see how it could be doing any useful filtering.
This return-pipe on ebay
https://www.ebay.co.uk/itm/174674508153 ... R5CZvKqaYg
looks just like mine - a completely solid pipe all the way between the top and the threaded-in back-pressure valve. How does oil get into the filter, to be filtered?!

[Billy26F5]

I don't know how you tried to post the pics but see how you manage with this: viewtopic.php?f=1&t=5024&p=53955#p53955
Sounds a bit like the filter you had wasn't actually right, as they're not supposed to be paper. I think the feed to the filter is from the valve, but you can't easily see it normally. see how the valve fits on to the pipe as I think that's where the oil will flow into the filter.
Sandy

[Redpla]

Sorry - full description of the filter: has a paper (or paper-like) concertina on the inside, surrounded by a perforated tin jacket. I've seen pics of s/h ones - mostly the ones included with a "Dexta hydraulic pickup (sic) pipe" on ebay. They look like mine.

Left the pipe to soak in the parts washer. Then applied air pressure to it. And, pop, a tiiiny hole (about 3/64" gauging from drill-bits) opened up. So my mistake, there *is* a hole in the side of the pipe, bleeding oil into the filter.

Seems the filter will work until the next time a rust or paint flake blocks it And I really don't have the enthusiasm to take the transmission/axle apart and get it to that level of cleanliness. Maybe I will one day, when the tractor is no longer in service and is retired just for road-runs.

[Billy26F5]

You shouldn't need to take anything else apart to clean the axle out, but it will be worth changing the oil to do so, and once the new oil is in make sure that you don't get too much rain falling on there as the water in oil emulsion is generally caused by rain going through the bolt holes and getting mixed in. The original filters have a very fine mesh to strain any dirt from the hydraulics. I did wonder that the hole might just be clogged up, should be fine as long as no water gets in there.
Sandy