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How to refill Armstrong shocks?

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Luke_Healey

Luke_Healey

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My car is basically riding as if it's solely on springs with no shocks. It looks like an amphibious car going down the road, as if I'm driving across heavy wake.

The shocks on all four corners look brand new. The car was restored in 1989 and I imagine these were rebuilt or bought as new pieces. Each one of them is wet with telltale signs of leaking.

I'm probably going to hit up Peter C for new front shocks when I get the money, and I want to convert the back to the monotube shocks as seen here in the forum recently.

So... None of the service literature I've found tells exactly how or what to do to refill the shocks. What kind of fluid do you put in them and where exactly is the fill hole? I removed the big nut from the top, but that looks like the valving system. I didn't think it was a place you'd fill them.

Do any of you have the lowdown?

I imagine a semi permanent modification to the front suspension is necessary to convert these cars to monotube shock front suspension? If not, and it's easy, I'd love to be pointed in the right direction.

Right now, this car is riding very unsafely and I'm wanting to tighten everything up.

Other than the poor handling, the suspension seems to be buttoned down. New bushings (well unused practically from 1989) and seemingly all new parts all around.
 
Not much to offer here as I'm wondering the same thing myself. Somewhere I saw a post that motorcycle shops have it. I want to check mine and I have no idea about this.

Does different shock fluid have a different valving effect?
 
Yeah, I read somewhere about using 20 weight motorcycle fork oil, but no instructions how how to put it in, drain the existing stuff out, or how much to put in.

Also, I didn't know if I had to remove the shock from the car to do this or not.

If I have to remove it, I'll just order new ones in some coming month and continue to drive the car under 45mph.
 
Hydraulic oil (like used in "hydrostatic" mowers). Available in different weights.

You can refill them on the car. There are small odd sized plugs. Then you'll need some tubing and a squeeze bottle. I used to top mine up and bounce the car, then let it settle, then refill. Eventually, I was having to do this at every oil change so I purchased some rebuilt units. So far I have not had to refill them, but I'm thinking about taking them off to empty them and put in fresh fluid. (It has been about 4 years)
 
I haven't worked with the lever shocks for over three decades but I remember buying fork oil from motorcycle shops and topping up as Trevor mentions. Like he said, there are several weights to choose from and the higher weight oil you choose, the stiffer the ride will be. Starting with 20W oil sounds good but if you find that too squishy, you can always move up to a thicker oil. From memory, we removed the shocks, removed the plugs and inverted the units to drain most of the old oil out, but you'll never get it all.
 
I my opinion you are wasting your time and it is dangerous as it is, give Peter C a call. They are not too expensive for his rebuilds and will last your life time.
 
Am I that far behind the times? I have not bought any lever shocks in the last 10 years. Is there something against using the oil that Moss sells specifically for Armstrong shocks? My experience is only with rebuild units from Apple Hydraulics and they have held up well on both my Sprite and MGB, but only have about 10,000 miles on them. I am not familiar with Peter C's. No leakage. My rears are originals that I flushed with mineral oil and refilled with Armstrong fluid and they still work fine. It's easier to do the rears if you remove them, but the fronts are easy. The oil Moss sells is in a bottle with a squeeze nozzle.
 
Nothing against the oil Moss sells except for the price and availability. Hydraulic oil works just as well. The rear shocks on my car are still is very good shape and to my knowledge have never been rebuilt. I flushed and refilled them about 4 years ago. The only reason I'm considering draining and refilling, is because when the oil gets old it seems to thicken and smell bad. So I thought changing it every five years or so might increase the life of the shocks.
 
Ok, I get the feeling most people recommend not to even mess with these shocks for safety reasons, but I don't understand that, since we send amateurs out all the time to service their own brakes.

I'm still not sure where the refill holes are and the way to ensure the proper level of fluid has been achieved?

I marked some logical bolts in these photos. Can any of you tell me which ones are the proper ones to use to refill the shocks?

661650258_305c0cc3f9_o.jpg



Thanks!
 
I have used standard Hydraulic jack oil, available at most auto parts stores for years without any problems. I have also used the motorcycle fork oil, which is essentially the same only slightly more expensive, and just purely on the basis of price cannot justify the Armstrong product except that it is the right "brand" for the "purist" but still essentially the same product! /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
"A". Don't take out "B" that is the valve.

Flush and refill'em and see if they work OK and how fast they leak. If they do not work or leak too quickly, then you can look into rebuilding them.
 
Ok /bcforum/images/%%GRAEMLIN_URL%%/smile.gif Thanks for clearing that up.

So to top them up, is it the same procedure as a rear end? Fill the hole until fluid runs out?

Like I said, these shocks look new, but have been sitting unused for the past 15 years. I am planning on upgrading the fronts and want to go with tube shocks on the rear. However, I don't get paid til tomorrow, and I want to drive today /bcforum/images/%%GRAEMLIN_URL%%/wink.gif

I'm also trying to see if stiffening the front shocks takes away my high speed shudder and cornering issues.

And I accept full responsibility for my actions. This isn't the first car I've worked on by a long shot /bcforum/images/%%GRAEMLIN_URL%%/wink.gif It's just 'different'
 
I put a set of rebuilt shocks from Apple on a 73 MGB once. Before the end of the summer they were leaking and worthless. Last time I needed shocks, I got them from World Wide (Peter C). That was a few years ago and they are still perfect.

For filling, I have the oil sold by moss, I stuck a small piece of tubing in the spout, and insert that into the small opening (top front of shock, remove small bolt) and fill it until it dribbles out.

I've heard of people using hydraulic jack oil to fill them, but I have no idea if thats a good choice or not.
 
The fill port for the rear is on top of the shock (again, small odd size plug)
 
Luke_Healey said:
Ok, I get the feeling most people recommend not to even mess with these shocks for safety reasons, but I don't understand that, since we send amateurs out all the time to service their own brakes.
Click to expand...

I don't get that admonition, either. But we each have our own level(s) of comfort, as to jobs we are willing to undertake, and jobs we feel are better left to others. Certainly, I have no hesitation in maintaining shock fluid levels myself.

On the original shocks, there is a natural (leather?) washer / bushing at the arm that *will* leak slightly, preventing the ingress of dust and contaminants. So low fluid level is not, in my opinion, a definite indicator of the need for a rebuild. Flush fluids, refill, and attempt to move arm in both directions. *That* tells you whether you need to drop $$$ on rebuilt units.

My $0.02 - YMMV.
 
Yes, the shocks weep in stock configuration, put they should not need to be refilled every 2000 miles.
 
No no, is safe enough to mess with them is just not safe to use em when not working.
 
Just want to chime in and say that this is one of the most informative threads I've ever read.
You guys are awesome.
 
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