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MG Midget and Sprite Technical - LA Damper Valves
| I have got about 6 LA Dampers from various places, and like a muppet removed all the valves so I can "tune" my suspension - aka play with it once I have fitted the Mamba / MGB front dampers.....
BUT On closer inspection one valve assembly is the later non o-ring type, I have peered into every one of the stripped dampers and can see no difference in the maching on the valve area - does someone have a picture/link info that will help me work out - A the right body to put the non-o-ring valve back into or B Feel safe that someone else has simply fitted the wrong valve back into the wrong body at some point in the last 60 years ( est ) of the life of the damper. Second a photo of a gold and a copper spring for reference Thanks Malc |
| Malc Gilliver |
| Malc, I note that not all pistons in la dampers have seals. The modern copy dampers don't even have rings on the rebound,; relying on a close tolerance fit to build the required pressure. So my guess is, that if the bores for the valves are the same diameter, with or without o rings the valves will work in either body. I guess you coukd try installing the non o ring type in all the bodies, filling with oil, and see how it feels cranking the arm by hand. Sorry, that's the best I can offer. |
| anamnesis |
| Just confirming this is what you mean. Read this 'The Sprite Forum' thread on the subject. Peter Caldwell of the US adjustable dampers explains I think what you need to know. https://www.ahexp.com/forum/the-sprite-forum.6/armstrong-damper-shock-valve-nut.272751/
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| anamnesis |
| Hi Malc Peter Caldwell also wrote this. "You want to be sure that the main valve body, the part with the hex nut, is correct for the casting. 1 takes an o-ring with washer, and 1 without. There is a depth difference, too. Good luck. Peter." https://www.mgb-stuff.org.uk/dampers.htm So you need to identify which is the later casting, whihj had the simplified non o ring valve body. |
| anamnesis |
| I have loads of spare bits if you need to make up a matching set. Cheers, Malc 2 |
| Malcolm |
| Thanks Anam, I'd found one of the links, but not the other one. I have looked at the top of the machining and couldn't see a difference - I think I will need to look again. I'm not up there till next Saturday, so I'll update then - possibly with pictures as I look for the difference ! Thanks "Malc2", tbh all I am trying to do is make sure that neither of the MGB dampers are where the non o-ring valve came from, but thanks for the offer, I might come back if I get stuck. |
| Malc Gilliver |
| Soooo.
Four different retaining fixings. Ver 1 - With a washer under the head, larger that the hex, o-ring and 2 holes in the body - 90 degree face (A30/35 rear dampers) Ver 2 - One piece with flange the same size as the washer, o-ring 2 holes in the body, small angle on the top face Ver 3 - One piece with flange the same size as the washer, no o-ring 4 holes in the body Ver 4 - One piece with flange the same size as the AF of the hex, o-ring 4 holes in the body And the small diameter springs are set between 15.5 and 17mm long with coils from 8 to 10....and 0 to 3 spacers ! Maybe it's time for telescopics ! |
| Malc Gilliver |
| Wow. Are they interchangeable or unique to a body type? |
| anamnesis |
| That is kinda my question !
But seriously, you can look at the casting and retaining fixing and work out the ones with the spacer. The others I think I have the one without the o-ring as there is a different wear line in the body ( I hope ). The one with the smaller washer was still assembled (the AHS lever arm I am replacing) The rest (3 off angled one piece fixing) I think are interchangable. Now I need to get my head around the small valve springs - what length should they be set to and which spring ( coils and thickness ) is which. But what I going to do is get the brake pipes sorted, the system bled and the engine back in and put the std single arms back on , so I can drive it while I try and work ou what settings to start with |
| Malc Gilliver |
This thread was discussed between 14/03/2026 and 22/03/2026
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