• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Lever Shock Oil Level

Share this page

AUSMHLY

AUSMHLY

Yoda
Country flag
Offline
Hello,

Seems almost every time I drive over railroad tracks, the rear shocks can't seem to handle the travel and I get a bang sound.
I remember this sound when my dad had his Healey. Is this common or is it time for new shocks?

When pushing down on the front and rear wings and they seem to travel and return at the same pace and distance, level out after a couple times. (I think the front shocks are fine, but if they are also worn out, then this comparison is no good.)

Before I remove the rear shocks and send them out to be rebuilt, I thought I'd ask here about adding oil. The rear shocks are not leaking.
I removed the top fill plug and slid a wire down. The wire bottomed out at about 1 1/4" No oil on the wire. If I move the wire around a bit, it will get past what ever is stopping it and 1/4" deeper I hit oil.

Where is the oil suppose to top out from the plug?
If it is low on oil, how can that be, if it shows no sign of leaking?

Could this be as simple as adding straight SAE 20w oil?
If so, how far down below the fill plug?

Thanks you.
 
Check the mounting bolts; the banging sound is almost certainly coming from a loose bolt (or bolts). If your shock was properly filled, doesn't leak and performs properly it shouldn't need oil. They should be filled to about the bottom of the shoulder of the top plate; i.e. you need some head space.

Edit: Sounds like your shock is low; but check the bolts before doing anything.
 
Thank you Bob.

All bolts are tight.
Where is the... bottom of the shoulder of the top plate?

Red line, Blue line?
Black line shows were the oil level is.
I think the bang is from the axle hitting the frame.
IMG_2717.jpgIMG_2717 2.jpgIMG_2717 3.jpgIMG_2718.jpg

When you say shock is low, as in not set up right? Unit gets bolted, but maybe the arm is not attached correctly?
 
Blue line (or a little bit higher if you want). Put some oil in and see if the banging stops; if it leaks it's rebuild time (if not, Bob's your uncle). I use Moss's Armstrong shock oil, but others report good results with fork or jack oil.
 
Would I be correct in assuming low oil would allow longer travel distance, hence axle hits the frame?
 
The axle hits the rubber pad in your last pic. Shouldn't be any banging. It would only do this if the suspension were "topping". I think that would be unusual.

Since we know the shock oil is low while the bolts are tight, low oil is likely the problem. Fill it up to just below the threads of the filler plug.
 
Steve, maybe because of the excess shock travel, the axle is hitting either the top bump stop or pad on the frame. The bang is not a metal to metal sound. I'm sure it's one of the bump stops. One can feel it in the car. Pretty significant.

Hoping one or both of the rear shocks are low on oil, as that's an easy fix. Still, curious why it's low, if there's no sigh of leaking.
 
If you have the car on a lift, or jackstands, unbolt the link at the top, and work the shock lever up and down, before and after you top up. Maybe, if you note more resistance after the top-up you won't need to pull the shock and send it off (watch for leaks)?

Note I haven't done this exact procedure--it's easier to test on the bench--but I think it would work.

Edit: Now that I think about it, you'll probably have to unbolt the link entirely (still easier than pulling the shock, though only slightly so).
 
Moss sells "Shock Fluid", 16oz. After tax and shipping it costs about $25.
Not sure what the Moss product is, or it's weight.

Healey Workshop Manual says use SAE 20w oil.

It's mentioned on forums that hydraulic jack oil can be used. However hydraulic jack oil comes in different weights, most being 5-10w and not all bottles list the weight, so it takes a little research to find that information.

CRC Sta-Lube hydraulic jack oil, SAE 20w, 15oz. Part number SL2621. Priced locally at shocking low $6.
BAEB1D96-EE37-4DC8-B146-8250A58D3A82.jpeg53437992-1CF4-4108-A81C-9D0C3E0E13D1.jpg

CRC Sta-Lube.
http://api.crcindustries.com/auto-services/get-pds/SL2621
 
Both rear shocks were down oil. I filled them up to 1/2" below filler screw thread.

I checked the fronts to find when I put a rod into the top screw filler plug and it hit the top of the (piston mechanism?) no oil. I'll assume that one is low too?
Do I fill the fronts same as the rear, 1/2" below filler screw thread?
 
1/4-1/2" should be fine. You just need head room for expansion.

Has anyone ever asked Peter Caldwell what he recommends/uses for shock oil?
 
If your lever-arm shocks are feeling perhaps somewhat worn or even worn out, is it worth trying a little thicker oil in them before throwing in the towel and sending them out for rebuild or installing new ones?
 
AUSMHLY said:
Both rear shocks were down oil. I filled them up to 1/2" below filler screw thread.

I checked the fronts to find when I put a rod into the top screw filler plug and it hit the top of the (piston mechanism?) no oil. I'll assume that one is low too?
Do I fill the fronts same as the rear, 1/2" below filler screw thread?
Click to expand...

Any resolution on the "bang" sound?
 
Have a look at the AH Spares site: when you check for shock absorber oil, one of the products is Castrol, and the photo shows Castrol Automatic Transmission Fluid TQ-F 1747 1 Litre. Doug
 
After filling one of the rear shocks, I had put too much oil in. I removed some of the oil to find it was blackish. So I drained all the oil, too black. Most likely the rubber is disintegrating, so it'll need rebuilding. Drained other rear shock, oil was clear. Since I'm rebuilding one, best to rebuild both. Neither rear shocks were leaking. Checked oil level in both front shocks, they were low, noticed both shocks were leaking. Front and rear shocks will be sent to WWA to be rebuilt. Will post results when I get them installed. Thanks for your help and the follow up Steve.
 
I received the 4 shocks back from WWA. I Put them on the bench to test them. One front shock doesn't have much resistance. I raised the arms on both front shocks to the top, released them at the same time to let them fall on their own. Shock with little resistance; the arms dropped in 18 seconds. Other shock, the arms didn't moved during that time. Rear shocks, raised the arms to the top, they stay there, don't drop on their own. What would cause the front shock to drop so quickly, 18 seconds? Air trapped inside from shipping? Will it get stiffer (the resistance it's suppose to have) from being active on the vehicle? One thing I find interesting is the shock that drops it's arms, the filler bolt (no marking on head) seems to be welded closed? Other plug CSF on the other front shock has a washer.

IMG_2789.jpgIMG_2792.jpg
 
Last edited:
Doesn't sound right to me; call or email Peter at WWA and ask him. WWA is considered the best in the business, I'd hate to think they're 'slipping.'
 
AUSMHLY said:
Thank you Bob.

All bolts are tight.
Where is the... bottom of the shoulder of the top plate?

Red line, Blue line?
Black line shows were the oil level is.
I think the bang is from the axle hitting the frame.
View attachment 61078View attachment 61079View attachment 61080View attachment 61081

When you say shock is low, as in not set up right? Unit gets bolted, but maybe the arm is not attached correctly?
Click to expand...

I agree with Bob about loose rear shock mount bolts causing the banging noise when you hit a bump. That happened to me many years ago, and not again after tightening until it occurred during our post-Conclave tour of the northern states after the recent Conclave in South Dakota. Everything was fine until we got off the Lake Michigan ferry on the Michigan side. The roads from there down to the Indiana state line were atrocious, and almost rattled my teeth. When we got to smoother roads, I heard the familiar banging in my left ear at each rough spot. The bolts don't have to be totally loose to cause the shock noise, but should be really tight or the shock can move on a bump. Not only did the rough roads cause the rear shocks to loosen, but it also caused the steering gearbox to leak temporarily. Same thing happened on the washboard dirt road to the top of Pikes Peak in 2002.
Unlike Bob, I have always filled my shocks to the top of the hole and have not yet had a shock leak or other problem with them. In their location, it's hard to see the level of fluid at anything below the top. When filled, it'll form a meniscus that causes the next drop to "roll off". After the 4,709-mile roundtrip to Conclave, I re-serviced my BJ8, and the shocks were still at the same level as when I left home.
 
Last edited:
Back
Top