Model A Shocks.
 

Any recommendations for what fluid to use in my shock absorbers? And maybe also, what NOT to use?

Re: Model A Shocks.
 

What shocks do you have? Original, stipe, apple ??
Are they dry now? If wet, can u determine what’s in them now?

Re: Model A Shocks.
 

Functional, do they work now, do they leak, are they dry?

Re: Model A Shocks.
 

most of the parts houses carry a shock oil that is pretty similar to hydraulic jack oil. Most are ISO 32 to ISO 64.

Re: Model A Shocks.
 

Ford changed the oil in the middle of the production. Clean out the shocks and use the oil supplied by our friends, the usual vendors.

Re: Model A Shocks.
 

Original shocks. One has engine oil in it. The other three have straight glycerine. Shocks work; not frozen. Is it possible to drain and clean of existing fluid without pulling them apart?

Re: Model A Shocks.
 

no they need to be taken apart. most of the time not an easy job

Re: Model A Shocks.
 

Jack is correct
Can’t clean inner chamber et al unless opened up.
It’s a chore.

Re: Model A Shocks.
 

I don't see anything wrong with the oils in the shocks.

I'd put the caps back in and declare victory

Re: Model A Shocks.
 

Glycerine is not oil. Hydroscopic, (water is not good inside the shock), Not compatible. Ford changed to hydraulic oil for servicing.

Re: Model A Shocks.
 

Re: Model A Shocks.
 

Don't know. Would bet the dealers could replace, the service bulletins indicate to me that the dealers had the tooling.

Re: Model A Shocks.
 

Thanks for your help folks.

Re: Model A Shocks.
 

Don't use glycerine, the change to oil came fairly early in production.

Most folks now use hydraulic oil and the weight depends on how much they are worn. Plus the shocks are adjustable.

Re: Model A Shocks.
 

The service bulletin mentioned in post #11 was issued in June 1930.

Re: Model A Shocks.
 

Houde Engineering Co. experimented with all sorts of fluids for their rotary dampers. They likely favored the use of glycerin due to it's properties when affected by cold and hot weather extremes. They also used mineral oils and castor oil during different periods trying to find a fluid that would be consistent and reliable for the normal life span of their damper designs. They generally stuck with glycerin for most of the types history. They used them on Ford vehicles till late in 1947 when Ford started to venture toward the tubular shock absorber.

Houde Engineering made them for low cost to Ford and they were considered throw away items back in the day. Other companies made similar units for aftermarket and replacement sales. Henry Ford always worried about strikes with his supplier companies so he seldom only had one source for any item used on his products.

Condition is everything in how these units function so many years after they were produced. If there is too much clearance in the wing shaft to housing fit then they need higher viscosity oils in order to continue providing a reliable function. There likely aren't that many units out there in stock form that will still function well using glycerin. They are difficult to repair for wear. It is likely less expensive to fabricate new parts rather than try to repair badly worn ones.

Re: Model A Shocks.
 

Pearson used 30-40 wt motor oil, I have been putting in 85-140 wt hydraulic oil.