The MGB Armstrong hydraulic lever shocks are one part that I imagine doesn’t tend to get the maintenance they really require. In reality all you have to do is unscrew the oil filling plug and keep the oil topped up. It appears as though this simple piece of maintenance is often overlooked.

In the case of my 1967 MGB GT there are no notes in my father’s records that indicate this procedure was ever performed. One of the shocks seems to work well but the other has no resistance and certainly needs a refreshing. The easiest way to refresh the front shocks is to buy refurbished ones from Peter Caldwell at Worldwide Auto Parts. He rebuilds them better than new for under $100 each.

Being cheap (or having already spent too much money) I’ve decided to take the shocks apart and do a basic refresh. Hopefully this will give them a couple more years of life! If not Peter Caldwell will get an order.

MGB Armstrong hydraulic lever shocks
MGB Armstrong hydraulic lever shocks

To access the inner oil chamber you need to remove the 8 screws holding the cover plate down. I managed to save the sealing gasket when removing the plate but I might cut a new one when I reassemble the shock.

MGB Armstrong lever shocks screws
MGB Armstrong lever shocks screws

This is the inside of the MGB Armstrong lever shock that wasn’t working properly. This shock has lost about half its oil so this isn’t too surprising. Once I clean the mess up and add new oil I expect the shock will work again unless internal damage was done.

MGB Armstrong lever shock low oil
MGB Armstrong lever shock low oil

The oil I drained from the shock looks like it came from a toxic waste site. It also smells terrible, does oil go bad? All those shiny specks of silver are very fine zinc (or possibly aluminum?) powder, obviously wear to the shock body.

Oil and zinc from MGB Armstrong lever shock
Oil and zinc from MGB Armstrong lever shock

There is also a very fine metal sludge on the inside of the shock. It’s recommended to not use any solvent when cleaning this mess up so I’ll use cheap light weight oil and rinse out as much of the sludge as possible.

Fine zinc deposits in MGB Armstrong lever shock
Fine zinc deposits in MGB Armstrong lever shock

The last step is to remove the shock valve and piston. These are the components and they look to be in good shape. I’m not sure if replacements would be available.

MGB Armstrong Lever Shock valve and piston
MGB Armstrong Lever Shock valve and piston

The MGB Armstrong Lever Shock that was working correctly has close to the right amount of oil in it although I expect even this is a little low. From first appearance there doesn’t appear to be nearly as much fine metal floating around but I’ll find out when I clean the shocks with oil.

MGB Armstrong Lever Shock oil level
MGB Armstrong Lever Shock oil level

Here’s the oil I drained from the working shock. There’s little fine metal dust apparent but big globs of something have been floating around.

Tomorrows job? Time to clean these ugly shocks and refill them. Stay tuned for the second installment.

MGB Armstrong Lever Shock ugly oil
MGB Armstrong Lever Shock ugly oil

Part 2 of Refreshing the MGB GT Armstrong hydraulic lever shocks

 

3 COMMENTS

  1. Kevin, if one of them is low on oil, it likely has a bad leak. I just replaced a front shock on my ’67 MGB, and it had made a puddle all over the floor. Once you refill them with oil, check for motion in the lever to make sure it has resistance to movement all the way up and down. When they fail, sometimes the lever will flop in its middle movement before it has resistance. You also have to put oil in and kinda burp the air out of them by moving the lever, until the air is out and the reservoir is full. Look for signs of leakage from the arm seals. The other failure in them is when the bushings are shot, and then the arm will be loose. You can use 20 wt motorcycle fork oil or hydraulic jack oil in the shocks.

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