Fibber Mcgee
Well-known member
What is shock fluid? I'm pretty sure I haven't seen it at the local parts store. Can I use ATF it seem like the closest thing being a hydraulic fluid?
Shock fluid?
- Thread starter Fibber Mcgee
- Start date
alanwoodieman
Well-known member
I use hydraulic jack oil which is 10 wt
There were three types of oil used: Gylcerin, Castor Oil and Hydraulic Oil. Apparently the type of oil used was particular to each type of shock absorber according to an original document I saw. The author was quite specific that what was originally used should be replaced with same.
However, if the shock absorber body and internals are the same I don't see why a specific oil must be used in preference to another, as long as the oil won't react with a particular material like seals, which might contain traces of the original oil.
Your nose might be able to guide you here (better still, the wifes nose) Castor Oil has a readily identifiable smell. Glycerin is thin and clear (after all these years?) And the Hydraulic Oil will look and feel like hydraulic oil, a little thicker and greasier.
However, if the shock absorber body and internals are the same I don't see why a specific oil must be used in preference to another, as long as the oil won't react with a particular material like seals, which might contain traces of the original oil.
Your nose might be able to guide you here (better still, the wifes nose) Castor Oil has a readily identifiable smell. Glycerin is thin and clear (after all these years?) And the Hydraulic Oil will look and feel like hydraulic oil, a little thicker and greasier.
rotorwrench
Well-known member
That is a question that I still haven't seen an answer for. Glycerin was the original fluid used by Houdaille but I've never heard of a chemical break down of the product marketed later as "shock fluid". I've heard that mineral oil, castor oil, and glycerin were all used in Ford products and some mention the shape of the filler plug was the indicator of type used.
Houdaille shocks originally used leather as the materiel for the wing shaft seals and glycerin will protect the leather. The glycerin stays about the same viscosity in all normal temperature variations. If a more modern type treated leather or some other mineral resistant seal is used then mineral oil can be used. As to what type or viscosity I don't know. The viscosity of glycerin or castor oil would have to be measured to see. Hopefully a shock rebuilder will add their 2 cents.
I still have occasion to to work on an old Bell 47 helicopter with a stabilizer bar set up now and then and they used the late type Houdaille dampers. They have a little window so you can see the fluid level and Mil-H-5606 hydraulic oil was used in them. We had to disconnect and time the drop on them with a specific weighted object attached to the arm each 100-hour inspection. They have a needle valve adjustment to get the time right.
Houdaille shocks originally used leather as the materiel for the wing shaft seals and glycerin will protect the leather. The glycerin stays about the same viscosity in all normal temperature variations. If a more modern type treated leather or some other mineral resistant seal is used then mineral oil can be used. As to what type or viscosity I don't know. The viscosity of glycerin or castor oil would have to be measured to see. Hopefully a shock rebuilder will add their 2 cents.
I still have occasion to to work on an old Bell 47 helicopter with a stabilizer bar set up now and then and they used the late type Houdaille dampers. They have a little window so you can see the fluid level and Mil-H-5606 hydraulic oil was used in them. We had to disconnect and time the drop on them with a specific weighted object attached to the arm each 100-hour inspection. They have a needle valve adjustment to get the time right.
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richard crow
Well-known member
years ago ford published a bultin about shock oil . it stated you could tell by the filler plug whitch type to use .squre, long plug, short plug, hex head, etc . but like my old gril frends i can,t find it. may be louie trique passed that info to bill when he sold his shock bussines. but there was different type of fluid used i think all the rebuilders today use hydl oil ask bill rotor wrench 1 thing for sure they did not use sky droll man that is nasty stuff ever get a drop in your eye i know you know what sky droll is
I've tried to copy the original document here but no joy there, here are the words from the Houdaille Service manual.
"Three types of fluid have been used by the manufacturer. Smell is the best way to detect the different types.
If the fluid has an alcoholic odor the fluid is of glycerine base. If the fluid has an oily odor, the fluid is of petroleum base. If the fluid has a vegetable odor, the fluid is of castor oil base. For shock absorbers having a glycerine base fluid, wash reservoir in water. For shock absorbers having a petroleum base fluid, wash reservoir in kerosene. For shock absorbers having a castor oil base fluid, wash reservoir in kerosene."
It appears you can use any of these three fluids. However IMHO Caster Oil or Glycerine would be the easier way to go. They are both readily available from a druggist or pharmacy and their viscosity and weight is unlikely to have changed since Houdaille used them.
Hydraulic oil on the other hand comes in many different grades and finding the correct one would I suggest be a hit and miss excersise.
One other thing which the manual mentions is to disconnect the shock lever and move it by hand back and forth as you add the fluid, this way the fluid gets into the inner chamber. Fluid is filled to the bottom of the plug hole.
Good luck.
"Three types of fluid have been used by the manufacturer. Smell is the best way to detect the different types.
If the fluid has an alcoholic odor the fluid is of glycerine base. If the fluid has an oily odor, the fluid is of petroleum base. If the fluid has a vegetable odor, the fluid is of castor oil base. For shock absorbers having a glycerine base fluid, wash reservoir in water. For shock absorbers having a petroleum base fluid, wash reservoir in kerosene. For shock absorbers having a castor oil base fluid, wash reservoir in kerosene."
It appears you can use any of these three fluids. However IMHO Caster Oil or Glycerine would be the easier way to go. They are both readily available from a druggist or pharmacy and their viscosity and weight is unlikely to have changed since Houdaille used them.
Hydraulic oil on the other hand comes in many different grades and finding the correct one would I suggest be a hit and miss excersise.
One other thing which the manual mentions is to disconnect the shock lever and move it by hand back and forth as you add the fluid, this way the fluid gets into the inner chamber. Fluid is filled to the bottom of the plug hole.
Good luck.
Fibber Mcgee
Well-known member
I can imagine the look on their face when I say I need some castor oil for my car
. 
rotorwrench
Well-known member
Luckily, I don't have to mess with a paint stripping hydraulic oil like Skydrol. That stuff is mostly used on the big airplanes. The helicopters I work on still used more simple fluids & lubricants.
Even MIL-H-5606 hydraulic oil has a tendency to separate & grow microbials & fungus. None of them are perect. The main thing is whether you can procure the stuff locally or at least easilly from some out of town vendor.
Fibber Mcgee
Well-known member
What years did they change the composition of the shock fluid? My owners manual says Ford shock fluid but not a specific type. I guess when you asked Ford for shock fluid they would know what to give you by year model
rotorwrench
Well-known member
It was probably sold in those 1 pint rectangular cans with the little pull off cap on the protuding spout. Ford sold a lot of products from wax & polish to 3 in 1 type lubricants & greases. Some of the old chassis parts catalogs show illustrations of the products like this. They were pretty generic and didn't have a lot of information on them like what is required now days.
Those old shocks were probably replaced more than they were serviced. It wasn't that expensive in those days and most folks would have looked at you kind of funny when you mention serviceing for their cars shocks. The guy at the service station was supposed to do that, or at least you hoped he was doing all that he was suposed to do.
Those old shocks were probably replaced more than they were serviced. It wasn't that expensive in those days and most folks would have looked at you kind of funny when you mention serviceing for their cars shocks. The guy at the service station was supposed to do that, or at least you hoped he was doing all that he was suposed to do.
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Fibber Mcgee
Well-known member
Thanks rotorwrench , they still look at you kinda funny when you talk about servicing your shocks.
rotorwrench
Well-known member
dccis9@hotmail.com
Junior Member
Hoe does one adjust these shocks .where is the adjustment and how is it done. is there a special tool.? thanks
jerry grayson
Well-known member
len47merc
Junior Member
Having recently been through this and ultimately biting the bullet and rebuilding all my shocks I can tell you that ALL of the rebuilders I spoke with use 30 wt hydraulic oil to refill the shocks after rebuilding. The original fluid in mine had turned to a dark-greenish, viscous paste that neither hydraulic oil nor castor oil will mix with or break down. Before sending the shocks out for rebuild I attempted flushing them and refilling with hydraulic oil and realized some improvement. For grins one shock was sent out for rebuild and I could not believe the improvement over the remaining three. It's worth the try but if your shocks have never been rebuilt or cleaned-out and refilled with whatever material you plan on refilling them with the likelihood is high that the fluids will not mix well and the true effectiveness of your shocks will not be realized. Good luck!
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Robert/Texas
Well-known member
Bill Wzorek rebuilt four shocks for me and they work great. He told me to use hydraulic jack fluid in them.
len47merc
Junior Member
Bill Wzorek is one of the rebuilders advising me to use 30 wt hydraulic oil. He also advised that the 30 wt hydraulic oil is what he uses when rebuilding and refilling the shocks. I was in the process of working with him on my rebuilds when his unfortunate health issues cropped up a couple of months back.
My best to you Bill if you are reading this and my hopes and prayers you are doing well.
My best to you Bill if you are reading this and my hopes and prayers you are doing well.
