My neighbour has purchased a 1975 franklin glide on.
The unit has four hydraulic stands. One leaks.
He was told by the previous owner to use olive oil in the system.
Is this right? Shouldnt it be brake fluid or similar?
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Be nice... if I wanted my school teacher here I would have invited him...
Try a heavier visc oil ? Eventually you'll possibly have to replace the O ring seals..
Being only one leaking ? Have you checked how much a repair is ?
Maybe less than you think ?? Safety and fluid on road will be a consideration !!
Consider a telescopic cover like bikes have on front folks to protect shaft, seals ..
I've been working on cranes. Excavators and Draglines for near 50 yrs.
next piston blowing a seal won't be the first,
We've only ever used sq\"flat" pressure seals for those rams.
An o ring wouldn't (I'd think) Have the bearing surface to take constant 2 to 4000psi
With up to 80 ton load on them.
Back and forth hundreds to thousands of times a day. 24\7.
Try Those French ones. always blowing seals they ran over 6000psi.
And my last excavator was a 160 tonner. with dual 12in boom rams. lifting the weight of boom
(Probably 50 ton) Plus over 30 ton in bucket all day, every day.
I have had some experience too with hydraulics and seals. O rings can be commonly round section or square. They both work the same. However the usual recommendation is to use the same as came out. The square style resists extruding out the gap better as Macka infers.
More important is the type of compound the o ring is made of. The common cheap kits sold may have poor quality compounds or too soft for hard or dirty work. Just take out the old one and take it and the leg into a hydraulic or hose repair shop. They have professional quality o rings in all sizes. There are metric and inch sizes which are slightly different and not interchangeable if you want a good seal.
Most hydraulic systems use an oil based fluid and the seal compound is made for that. Mineral oil, or olive oil, or ATF, or hydraulic oil or even engine oil works ok. However brake fluid is something different and should not be used unless specified. There are seals made for that too but they are not the usual o rings. The same should be said for seals designed for water and taps. They are usually not resistant to oil and fail quickly.
Jaahn
-- Edited by Jaahn on Friday 12th of May 2017 02:47:02 PM
Yep worked on EPV's for 40 years .. up to 30m or so high ..You learn to trust them little seals !!
Worse part if hydraulics have a high pressure leak when there's an electrical fault up there . .. it's instant BBQ .. I've lost 2 work mates in the days when they had external coil springs to prevent hoses from bending .. They become a fuse when pulled over 415V LV..
Eaglemax - I agree with Jaahn you need to use fluids and seals that are compatible in order for the seals to remain effective. Just as an example in my previous life working in an aluminium smelter we used a water glycol fluid (30 to 40% water) on our cranes to reduce the risk of fire and it was only compatible with PTFE (teflon) or buna seals. Hydraulic leaks could have been catastrophic as the tools on the cranes were inserted into the electrolytic cells with molten material that was up to 1000deg. C and had 240Ka of power running through them. We had 26 cranes valued at nearly $7M each so a hydraulic leak that resulted in a fire not only had financial implications but posed a huge safety risk to our operators.
Although this situation is nowhere near as critical I would suggest that in order to avoid early failures your neighbour seeks the advice on what fluid and seals to use from someone with hydraulics expertise or as AK suggested maybe gets a trades qualified person to repair it for him. As Sol used to say on that old TV ad "oils aint oils". Your neighbour can't complain too much, assuming that these seals are still the original components 42 years is a pretty good life.
