VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1933-1936 Installing shock absorbers

Hope this not too ignorant of a question, or been answered before:
I have 4 rebuilt shock absorbers to put on a 36 standard (FC)--or at least they are supposed to have been rebuilt. They came from a warehouse and were advertised as being old rebuilds. There is evidence of them being worked on and they have some fluid in them.
1) What fluid to use in them? I have several cans of NORS 1930's vintage shock absorber fluid--use this? Or, use regular hydraulic jack oil? If the original shock absorber fluid is used, can hydraulic jack oil be added later?
2) Are the shocks filled to the brim--or does one need to leave an air gap?
3) Do the shock arms need to be worked back and forth while putting fluid in--to make sure completely full?
Thanks!

1. I would use fresh jack oil to top off - I would drain the old oil and fill with fresh jack oil.....other oils can be used but the jack oil is cheap , readily available and the old containers of some brands had shock filling mentioned on the lable.

2. with shock in the instaled position it filled full to the filler hole.

3. Moving the arm up and down will help to remove air.
The shock will have resistance on the down stroke only - arm will raise to the top position by itself if shock is working properly.

Hello folks,

Hope you don't mind a few more questions:

I have the shocks. In fact, I've sent one set back to the seller for replacement or checking because I wasn't sure about the rebuild status. Plus the first time the seller sent four rear shocks--had the wrong arms for the front. But now have the final set of four front and back from the seller. The seller is paying the shipping costs back and forth and I'm convinced he is making an honest effort.

To restate, these are old rebuilds--not newly rebuilt. The seller did not rebuild them himself.

1) They were sent with a little fluid in them but not anywhere close to being filled to the filler hole. The seller says this is normal. These are not leaking. I noticed in some of the earlier shocks he sent that they had more fluid in them, but they leaked during shipment (hard to tell where the leaks were because smeared everywhere). So that's why I sent them back, along with the wrong arms on two.

So the question is: What are the chances of them leaking once filled and installed? Is the packing gland cork--and thus could it have dried out and leak after installation?

2) The shock arms have resistance on the downward stroke--at least more than the spring. But one of the front shocks is questionable--when pressed down, there is some resistance, but the arm flies right back up. On the other shocks, the arms come up slower.

So the question is: Should the shocks return slowly after the down stroke, or can they spring back fairly quickly? Once filled with fluid, should they behave differently?

But by trying to go on the relative cheap I guess I'm getting what paid for: having someone rebuild the ones on the car I understand costs $120.00 upwards each --I'm paying about a 1/3 of this cost for the old rebuilds.

Thanks again!

The amount of fluid in a rebuilt shock would have depended on who rebuilt it.Chevrolet did not offer rebuilts.
Fill the shocks with hydralic jack oil and see what happens.The seal could be cork or the rebuilder could have used another material.
When the shock is full of fluid the lever should pull down with resistance.Not just from the spring but the fluid going thru the valve will slow the movement.The shock that the arm "flies right back up" is the one that is working correctly.The spring behind the piston is doing this and the piston is free in its bore as it should be.The other shocks may be gummed up inside or???Perhaps flushing them out and refilling with new fluid and a little "movement" will get them working as they should.

Chev Nut,

Thanks for the information--I'll give it a try!

Hello Chev Nut or others,

I thought about starting a new thread, but keeping this one:

In sum, installed the shocks, drove the car for about 100 miles, and they all work great with no leaks except one: the passenger side front shock leaks badly around the shaft.

If I get the seller to refund some $$, would it be feasible for me to put in a new seal? When these were rebuilt, the arms had been spot welded back on. So I figured we could grind off the weld, take the arm off (putting a witness mark across the shaft and arm to get back at the same angle)and put in a new seal. Could one use a modern O-ring seal? The shock works fine, but just leaks.

Could the shaft be scored and thus causing the leak?

Wasn't there an article in the G&D about rebuilding these single action shocks? If so, does anyone know the citation to the article? (what year, month)

Thanks again for everyone's help!

I don't recall an article on the post 1931-32 shocks.

After sitting on the shelf for 50 or 60 years the seal may have stuck to the shaft and /or broken up.

Its just a risk you take with old parts.I would keep the shock and "play with it"

I have never attempted taking a shock apart but your thoughts sound like they could work OK.The seal could be made up from several different materials.Keep us informed

Hello Chevgene and others,

Still plugging away intermittently on the shocks as time (and distance--currently living a long ways from the car) allows! :rolleyes:

I recall an article on rebuilding the 31-32 shocks--do you or anyone else recall what issue of the G&D that was in?

Maybe the the 31-32 shocks are similar enough to give clues on the 36 shocks. The main mystery is in getting the packing cover/gland off of the shaft--I've been told this is a tricky part that called for a special puller, and it takes very little to get me confused!. :confused: -

My old issues of the G&D are packed away because of moving--but I have access from someone else and can get the article.

Does anyone have ideas on how to pull/remove the cover that contains the seal on the shaft? It appears to be a press fit, but very little to grab to pull it off with.

Thanks again everyone!

The article was in the December 1992 issue of the G&D, Volume 31, Number 12. Pages 9 thru 13.

Hey Junkyard Dog,

Thanks very much for the complete and detailed citation!

By profession I work in a library and sometimes people mess up the citation part when asking for a publication. One faculty member recently wanted a particular book and insisted the author and title were exactly right. Discovered he was mostly wrong--but close enough so it could eventually be tracked down!

You bet! Glad to help out.

the 31 - 32 shocks are rebuildable they have a set screw on the rocker inside that can be removed and slide the shaft out and replace the seal the 35-36 does not have the setscrew and is pressed on the arm is pressed and spot welded on very difficult to get off and back on i drilled a hole on the opposite end of the arm put in a 50 ton press and could not push the shaft out just bent my pushing tool some one may have a better answer to the problem pushrod

I had a small leak on a shock from my "38" HB Sedan. I cleaned around the shaft with starting fluid, Packed RTV around the shaft, and took some plumbers graphite string and wrapped it tightly around the shaft. It weeps a little but does not run out. Mac

Just to let folks know the outcome and a possible fix for leaky shocks:

All four shocks now on the car, working with no leaks!

1) Took the offending leaker apart by grinding off the "bradded" over section that holds the shock arm on the shaft, pulling the arm off with a gear puller(first putting a witness mark across shaft and arm it would go back on at exact same spot), and then using a pipe wrench to twist off the cap that holds the seal.

2). Took out the old cork seal, cleaned the cap real good and used JB Weld to glue in NAPA neoprene seal # 7443 (I think this is for a power steering pump). The friendly and knowledgeable local NAPA parts man matched things up for me. Let cure at least 24 hours.

3) Press the cap back on the shock body (with some heavy duty gasket sealer around the body); Press the arm back on, lining up witness marks; Spot weld the arm back (also put a wet cloth around the shaft to hopefully prevent heat damage to the seal) I know this is not for show cars or for those concerned about welds showing, but it works fine for a driver car.

4) Top off with hydraulic fluid, put on car.

I've now driven the car at least a couple hundred miles, no leaks and shock works fine.

Just one more comment:

Having functioning shock absorbers really improves the handling and ride of the 36 standard. I used to have to fight the steering as the car wanted to wander all over the road with the slighest bump or rut, and it still wants to a little, but the shocks make for much better steering--not nearly as much correction needed for the road imperfections. And of course not nearly as bouncy!

So for those who drive and tour their cars, I think working shocks are a definite asset.

Thanks for the encouraging words,my shocks are being rebuilt ask we speak,chef-

Also the info is great for any one restoring later model shocks.Should be of great help for some one