Lever arm damper failure! Daimler SP250
Discussion
This is not as rare a failure as one would like to think and most likely down to simple metal fatigue. For those of us with lever arm dampers, how many times have our dampers been rebuilt over the lifetime of our cars? A fair few for certain. Replacement arms are readily available so there's nothing to worry about. Also, I have lost count the number of times people have mentioned to me that they've experienced a broken modern coil.
v8250 said:
For those of us with lever arm dampers, how many times have our dampers been rebuilt over the lifetime of our cars? A fair few for certain.
recon rear LA dampers for a MGB retail at about £18, take off 20% VAT, the retailer mark up and transport costs it doesn't leave a lot for the actual work and who knows how well or not the unit has been looked after in its possibly many previous lives v8250 said:
Replacement arms are readily available so there's nothing to worry about
I didn't know that, is it easy to remove the broken arm and fit the new arm?I think you can get new units in the USA but I might be out of date with this, last time I saw the dampers were about £90 each, I also know there's a US company that's supposed to do proper reconditioning of existing units
davepoth said:
Actually, it shows how good leaf springs are at damping.
Indeed. Given the age and lack of maintenance of most lever arm dampers out there I reckon you could take them off and not notice anything. The ones on my Dart and Morris Minor look original, it would be interesting to compare them with new ones.Quick update. The damper was not seized and no sign of leaks. Attached is a photo of the cross section. Very strange, like its got a steel core with a cast alloy casing! Is this how they were originally made? Failure looks like it was sudden by the clean-ish break. I bought a rebuilt repalcement for about 80 GBP from a Daimler spares guy here in the US and that looked like it was all steel.
Is that aluminium or chemical metal round the outside?
I ask because given the rusty centre, plus the fact all the armstrong LA arms I've worked with have been simple steel (as the centre of that arm is) plus when you look at the first pic it appears there is a step just after the break. Does make you wonder.
An above poster has summed it up, the recon fees on these are too low, they aren't that hard to recon, I've been maintaining mine for years, most of the time all that is needed is a top up of oil, infact I top mine up every service, they do leak in service and a top up is usually all that's needed, a recon is often a top up of oil and a paint, not a recon in anyones world but when the final sale price is sub £20 and you need to sand blast them down, fit a new bolt to the arm, fill them with oil and paint them how much more work can you do and keep that profitable?
I actually like LAs, but they (and the recon versions) must be looked after and seen with an open mind accepting their shortcomings.
I ask because given the rusty centre, plus the fact all the armstrong LA arms I've worked with have been simple steel (as the centre of that arm is) plus when you look at the first pic it appears there is a step just after the break. Does make you wonder.
An above poster has summed it up, the recon fees on these are too low, they aren't that hard to recon, I've been maintaining mine for years, most of the time all that is needed is a top up of oil, infact I top mine up every service, they do leak in service and a top up is usually all that's needed, a recon is often a top up of oil and a paint, not a recon in anyones world but when the final sale price is sub £20 and you need to sand blast them down, fit a new bolt to the arm, fill them with oil and paint them how much more work can you do and keep that profitable?
I actually like LAs, but they (and the recon versions) must be looked after and seen with an open mind accepting their shortcomings.
I had a similar problem on my Dart, although it was the lugs that bolted to the chassis that had broken. When stationary, there was nothing visibly wrong as it all rested in the right place, but as soon as you moved off, there was a clonking that increased with speed. It took a lot of looking to eventually find it.
Apparently the telescopic conversion makes a massive difference to the rear end, I'll be doing it when I've got over my respray, (8 months, but up to 3rd coat of primer & looking good)
If you do this conversion, there are some kits that bolt straight on to the original mounting points and some that require a certain amount of surgery.
I bought a set of NOS Armstrong Selectarides c/w wiring loom and controll knob, as fitted to Interceptors, Gordon Keeble, and DB6's - these would fit the Dart but will be on Sale at Beaulieau, (purely to help fund the respray)
Apparently the telescopic conversion makes a massive difference to the rear end, I'll be doing it when I've got over my respray, (8 months, but up to 3rd coat of primer & looking good)
If you do this conversion, there are some kits that bolt straight on to the original mounting points and some that require a certain amount of surgery.
I bought a set of NOS Armstrong Selectarides c/w wiring loom and controll knob, as fitted to Interceptors, Gordon Keeble, and DB6's - these would fit the Dart but will be on Sale at Beaulieau, (purely to help fund the respray)
Have you tried scratching the smooth alloy-looking surface with a pointed instrument? If the scratch isn't shiny (at least for a couple of minutes) then it isn't metal and someone's been bodging with the chemical metal.
It's also a bit odd that the profile of the "alloy" casing appears to vary around the circumference of the break.
It's also a bit odd that the profile of the "alloy" casing appears to vary around the circumference of the break.
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