Lever arm damper capacity

Technical MGB discussion
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David Witham
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Lever arm damper capacity

Post by David Witham »

Can anyone tell me how much oil an Armstrong lever arm damper is supposed to hold?

The dampers in question are the front ones with 2 arms but I wouldn't be surprised if the front and back held the same amount.
Vic Butler
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Re: Lever arm damper capacity

Post by Vic Butler »

The repair operation manual just states to fill to the level of the filler plug.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
Ian Fozzard
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Re: Lever arm damper capacity

Post by Ian Fozzard »

David, take a look at this:

https://mgaguru.com/mgtech/suspensn/fs110a.htm

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Peter Cresswell
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Re: Lever arm damper capacity

Post by Peter Cresswell »

Hi Ian,
I would agree with that link. When I upgraded the valves in my front dampers I bought a 500ml bottle of Penrite, and used a little over half of it. Penrite offer 2 versions; Shock Oil 1 for normal applications and Shock Oil 2, which is thicker, for competition applications. The bad news is that if the rears have the same capacity as the fronts you will need 2 x 500ml bottles.
For competition uses it is wise to leave a small air gap above the oil level because the oil will expand as it gets hot and pressurise the seals leading to leaks.
Pete
1969 MGB Roadster
2020 MG HS Exclusive
2007 Mercedes SLK
Plus 34 other cars since 1965
David Witham
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Re: Lever arm damper capacity

Post by David Witham »

I have now completely emptied and refilled the dampers. 200ml went into each one.

When I used to compete on sprints and hill climbs I fitted both uprated valves and number 2 oil in them. As I retired from that 8 years ago I have been changing back to number 1 oil but keeping the uprated valves.

At the same time I have taken out the short 550 lb/in springs and replaced them with longer 480 lb/in.

I am get it a bit softer for touring but not as soft as standard.
Vic Butler
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Forename: Vic
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Location: North West Hampshire

Re: Lever arm damper capacity

Post by Vic Butler »

Somewhere in the depths of the garage I've got a pair of Armstrong rear adjustable lever shocks.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
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