Shocking Discovery

[Kevin in NJ]

Just experimenting today.

I got my 1 9/16" socket in the mail today. I borrowed a 3/4" impact and set up about a 6 foot bar.

The 6 foot bar did nothing.

The impact did nothing with a shock sprayed with Kroil a few days ago.

I heated the shock to about 400, checked with IR temp gun, and let cool till Kroil stayed wet. Let it soak for a while.

Impact did not move it.

Heated back up to the upper 300's (was still around 200 when I started) and resprayed when it cooled.

Went back at it with the impact and it moved! Yaaaaa!

The insides were exactly as I expected. Packed with rust. I have a few known bad shocks to experiment with techniques. I am trying some other ideas so we will see what I have happen.

[Tom Wesenberg]

I took apart a tight shock about 5 years ago and it looked the same inside. I'll just save it for a show and tell piece.

[28ACoupe]

When I did the ones on the coupe, I had access to a 1" impact driver and it did pretty well. You really need something that is going to give you well over 1000lb/ft torque to break these things loose sometimes.

[Bill Underwood]

Build a charcoal fire and put several in the coals. Helps to put some oil in them. Let them cook till they go cold. Btw they will spew and stink so be aware.
My experience that 3 out of 4 will then disassemble. After that resort to a torch and quenching
I quit building shocks several years back because only 20% or less were found buildable

[Mitch//pa]

when using a 3/4 or 1" impact make sure you use 1/2" airline and 3/8th couplers or you wont get the full potential from the gun.
the 3/8th standard air hoses with 1/4 nipples wont cut it...

[Kevin in NJ]

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Let me add some background.

I prefer to not over heat the shocks as my gut instinct says red hot has to change too much of metallurgy. So I purposely tried to keep under 400 degrees on the big threads.

I just got 2 more shocks to open up. I used a small oven that I picked out of the trash. Both were heated to the high 300's and one was allowed to cool some and squirted with Kroil. The other was heated and quenched in water twice. I also started pulsing the impact in a few second bursts.

The valve will likely need much more heat to get progress, but I have not got there.

In my shop I only have the 3/8 fittings as I learned early the HVLP guns do not like the 1/4" fittings.

Why am I doing this?

I have about 22 shocks that are all likely to just need tear down and resealing. I need to get them apart nicely. The funny thing is out of all those shocks I am not sure I have 4 matching covers. If I do have 4 matching what are the odds they will not be correct for late 31?

[Model A Man]

I have never taken apart a shock so I don't know what the inside looks like, but would it be possible to make the inside into a friction shock but appear original on the outside. Just me thinking out loud

[MikeK]

FWIW, Milton has a "V" series of air couplers specifically designed for HVLP guns. They are 1/4" thread, but instead of the 40 CFM rating of the standard 1/4 "M" they are rated 74 CFM, near double. Thats more than the 55 CFM rating of the 3/8 "M" series!

As an added bonus, the couplers also accept the old standard 1/4 M fittings so you don't need to change over all your shop male plugs, only those that need high CFM.

Here's a comparison picture I brazenly ripped from SkyMaster on our 'other sister', the Garage Journal. Note the big difference in the hole size of the old 1/4" Milton M on the right. I'm currently in the process of changing over to "V" myself. Be sure to use quality 3/8 hose.


Here's a top view of the M & V series. 30CFM vs 74CFM
Again, your old M males will fit the new V, but at the old flow rate.

[Growley bear]

Kevin,

if you have enough shocks for another experiment, have you tried boiling one in water for awhile. Water is mostly the cause of rust in the first place.
Might work.

Chet

[calvin amerson]

fwiw thought I have in the past been able to loosen stuck parts by boiling them in peanut oil , already has lubercating properties! just add heat works fine.+

[dave in australia]

With a bit of work Kevin, that shock can be repaired and put back into service. I have started with worse than that. If your going to sell the shocks, then its uneconomical, but if its just for yourself, then its worth while to experiment and develop skills while restoring the shocks.

[Bob Bidonde]

Late 1931 shocks have reinforced mounting lugs, so the bases are different. There is little to no joy about rebuilding Model A shocks unless you are fortunate enough to find a greasy set with no rust and no shaft play. This is not likely to happen!

I bought a set of 1931 shocks rebuilt by Robert Paul of Yoder, Colorado. Robert has been restoring Model A shocks for 38 years, and his work is excellent. He advertisies in the Model A News, and he can be reached at 719-478-5102.

Maintaining original shocks in a cruising Model A is a pain in the part we sit upon!

[tbirdtbird]

Haha. I recently drove a customer's car which had no shocks at all. It drove exactly the same as any Model A I have ever driven that had either repops or restored originals...badly.

[Kevin in NJ]

Sorry I have to chuckle, I would not consider it worth my time to restore any of the 4 shocks I took apart in experimenting. They each have about 1/8" of play on the vanes.

I pulled out my very heavy pile of good shocks. A few are apart already and they look like new inside. I am going to dig out the article on shocks and label the shocks and covers so I know what should go where. Then I am going to tear down the shocks and select the best. Just more inside the warm basement work.

FWIW,

A Model A with good springs and no shocks is a nightmare to drive over 25 MPH. Been there done that, the test drive on the car before you get the shocks done- NOT FUN!! Almost went off the road.
Put original shocks on the car and no problems all the way up to 65+ MPH.
But I seem to be in the minority in my experiences with driving the A.


The guys at shows running 45 (their top speed) you can see the springs are wore out and the eyes are pushed out and rust dust all over. They do not have to worry about bounce cause there is none left.

[mhsprecher]

I have reproduction shocks on my town sedan. Last summer, I was driving and hit a bump and I thought I was going to lose control of the car. It really scared me. After some research, I came to the conclusion that the best approach was to get some rebuilt shocks. It took a while, but I finally got four good, rebuildable shocks that I sent to Robert Paul. I got them back, but have yet to install them.

A month or so ago, I noticed that I had lost one of my shock links. I had a replacement that I cleaned and painted and got some new parts for. When I installed it on the car, I realized that that shock had no resistance in it. The arm moved easily by hand. I put the link on it anyway, but I look forward to installing my rebuilt shocks on my car. From everything I have read, it will make a big difference.

[kp]

I rebuilt 4 shocks for my 31 ,Broke my 3/4 drive 1 9/16 socket on one of 'em and also ruined my large old cast iron vise ,was using a 6 foot piece of pipe on the breaker bar ,my air wrench wouldnt touch it . In rebuilding 4 ,went thru about 10 to find 4 that were rebuildable. Not goin to that Bar B Que any more . But my 31 drives badly all new front stuff ,thinkin on goin to 16 inch tires .

[pat in Santa Cruz]

a new set of shocks on a rusted solid old spring will not make any difference in the driving of the car. That's why you often hear there's no difference in a car with or without shocks. If you have driven a car with a restored spring and no shocks, you will most definitely notice a set of good shocks once they're installed.

The covers are interchangeable if you need to make a matched set, but as noted above, the bases on a 31 are very different.

[dave in australia]

Originally Posted by Kevin in NJ

Sorry I have to chuckle, I would not consider it worth my time to restore any of the 4 shocks I took apart in experimenting. They each have about 1/8" of play on the vanes.

I think it might come down to economy of scales etc. Down here in Oz, we generally don't have the luxury of finding NOS, or good rebuildable items that often. And with the exchange rate and freight, a lot of items are just out of reach for the average punter here if they decide to purchase second hand from the USA. So we tend to be a bit more willing to spend time in repairing and restoring what others would not even consider. But, if you feel that your shocks are not worth rebuilding, feel free to send them down here to me.