Broken Shock Mounts

AH67AH · May 18, 2020

My BJ8 has the Bilstein shock conversion installed. They were put on over ten years ago but have minimal mileage on them, because the car was laid up a couple years after installation. Just before going into storage, one of the rear adapters failed in spectacular fashion. I just discovered it while working to get the car back on the road.

The bracket is only supported at the bottom, with a long upright to hold the top of the shock. This entire top piece is what tore away. It looks like a lack of support and/or insufficiently strong material is the cause. Has anyone else experienced this issue? It seems like a simple gusset could have prevented the break.

I emailed the manufacturer and he notes they have changed the design and beefed up the materials, so I assume this isn't the first failure. He offered to sell me new mounts at $85 each. Has anyone seen or used the newer design who can tell me if they're worth buying, or perhaps I should have my own mounts fabricated? I guess there's no warranty on them, unfortunately. Any input appreciated, thanks.

HealeyBN7 · May 18, 2020

It looks rather homemade. The failure is likely due to undersized materials and the lack of boxing of the tube/channel. The good news is the weld held. It looks like it is possible for the channel to defect with the shock load (parallelogram) and that is what caused the fractures to develop and cause it to rip away. Shock loads are significant.

Good that you are asking about failures as one should never have to worry about structural failures when driving a car on the street.

I would be hesitant to accept a replacement product without some evidence of engineering or testing. Engineering modeling/stress testing can now be done on-line with simple programs.

It doesn't make sense that the vendor won't honor a free replacement??? Did you show them these photos?

Dean

steveg · May 18, 2020

Is that an early Udo?

$85 each for replacements sounds reasonable after 10 years of use. Sounds pretty close to cost.

If you don't do your own welding, you'd have a tough time making new bottom pieces and welding them up for that price.

I know. I built my own setup and bought out the machine work and welding and overall it was almost as expensive as buying his.

Bob_Spidell · May 18, 2020

I just had a similar break--good weld, metal fatigue next to it--on a shield I fabbed for my lawn edger. I'm not a metallurgist, but I think the heat of the weld changes the crystalline structure of the metal, making it more brittle, esp. where there's a lot of vibration. Anyway, if it is a Putzke setup the new ones look more rugged. What is it bolted to?

AH67AH · May 18, 2020

Yes, it's a Putzke setup. It's attached just how you see in the second photo above. Two bolts on the bottom of the L section.

HealeyBN7 said:
It doesn't make sense that the vendor won't honor a free replacement??? Did you show them these photos?

I sent him the same photos posted above. He asked if the car was lowered (it isn't) and noted "We have made some more changes from the early version to today and recommend to switch both brackets (left/right). There come with new upper hardware and stronger material." These new brackets are what I'm curious about. I really don't want this to happen again, especially if my wife is driving. I mean, it's a suspension part not a speaker bezel. The sound it made banging against the chassis was... interesting. The other option is to go back to stock shockers, but new brackets would be cheaper and easier.

steveg said:
$85 each for replacements sounds reasonable after 10 years of use. Sounds pretty close to cost.

With due respect, it seems to me that something like a shock mount shouldn't have a service life of a couple years of use. It should certainly outlast the shock that's attached to it. Especially when there are maybe 2,000 normal driving miles on it. I get that he's probably a one man show and I'm not trying to pick on the guy or anything, I just want to make sure I'm buying a safe and properly engineered product. Hence the query to to group.

Thanks for the input so far, it's appreciated.

steveg · May 19, 2020

AH67AH,
Udo's got a lot of kits out there. He's the main go-to guy for this. He should be able to fix you up.

In 2005 I installed the Cape rear shock kit. The bottoms broke in 2007. Didn't want to replace them with the same design, so I designed my own lower mounts and beefed them up a couple of times when they also bent.

These are low-production items, so sometimes they have to be developed by testing in the field (by us).

AH67AH · May 19, 2020

Fair enough, but considering the kits are designed by an engineer at one of the biggest shock manufacturers in the world, and advertised as having a lifetime warranty, I figured they would have held up to minimal road use. Especially considering the $1100 price tag. So hopefully it's understandable that I'm a bit gun shy to send yet more money on new brackets.

steveg said:
These are low-production items, so sometimes they have to be developed by testing in the field (by us).

I've been driving vintage cars of all types for a very long time, so I'm not really looking to be a test subject. Hopefully more data will emerge on the reliability and design of the new mounts. Someone off-list sent me the latest instructions for the kit this evening, but they show exactly what I have.

vette · May 19, 2020

In my mind a shock shouldn't bend itself or break its mountings. The shock would have to bottom out on its travel to bend itself or break its mountings or its location/geometry is really wrong.

RDKeysor · May 19, 2020

I've had no problem with the Putzke shock kit that I installed on my BN7 several years ago. Creating sturdy mounts for tube shocks on these cars strikes me has pretty challenging, and the arrangement that Putzke developed appears to be mechanically extremely stressed. But isn't it true that this Bilstein shock system is a pretty standard fitment on race-prepped Healeys, just as Weber carbs replace the SUs? I think the very limited travel possible with the Healey rear end design means really harsh tire impacts hammer the components more than you would expect in more typical rear suspensions.

Bob_Spidell · May 19, 2020

AH67AH said:
Yes, it's a Putzke setup. It's attached just how you see in the second photo above. Two bolts on the bottom of the L section.
.
.
.

Ah, that 'splains it; for some reason I thought it was front shock setup (I took a speed-reading course).

red57 · May 19, 2020

AH67AH
A different approach is the Koni tube shock kit from the '60s. I have had a set of these for over 20 years (including 15 years vintage racing) and never had a problem with the mountings. Initially I was worried about the strength of the sheet metal for the upper mounts but there has never been a crack.

Koni hasn't made these kits for many years but the fabrication of the mounts is fairly straightforward.

Attached is the installation instruction sheet for the rears - the only thing it doesn't detail is that the lower bracket for the right side is offset to move the shock inboard enough to clear the Ebrake cable and therefore the location of the upper bracket is also moved inward a bit. (I don't have dimensional info or remember exact offset because I modified mine to match the left side and changed my Ebrake cable mount accordingly)

I'm not advocating anything here but just showing another way that has been done since the '60s. Down side is it required drilling holes in the bodywork and I completely understand why the other mounting system is attractive to most.

Note to anyone considering making their own mounts to copy the Koni setup shown here: I would be willing to share photos and dimensional info with anyone wanting it, but be aware that Koni quit making this particular shock a few years ago so you would need to find a shock with the length and stroke to work. The Koni rear shock part number is/was 80-1504.

I was lucky and found an original uninstalled kit on ebay 25 years ago - probably not much chance of finding one now.

just food for thought.

Dave

steveg · May 19, 2020

Below is my solution for the last 13 years.

Having said that, think the most cost-effective way to solve the broken-Putzke problem above would be to try to get the best price from Udo, examine the new parts and if not satisfied weld on reinforcing gussets and maybe a tie-rod between them.

Cape upper mount similar to Koni:

New lower mounts:

blueskies · May 19, 2020

If the price seems too high, for this or anything else, just divide the price by 10, which puts it into 1970s dollars. $85 divided by 10 is $8.50. It's a no-brainer bargain.

I follow this rule with lots of purchases. They sound a lot more reasonable that way, and my wife seems to buy it.

steveg · May 19, 2020

blueskies said:
If the price seems too high, for this or anything else, just divide the price by 10, which puts it into 1970s dollars. $85 divided by 10 is $8.50. It's a no-brainer bargain.

I follow this rule with lots of purchases. They sound a lot more reasonable that way, and my wife seems to buy it.

$17 for both sides. Still a virtual bargain.

AH67AH · May 19, 2020

Hey, if that was the actual price then I'd be first in line! But my bank account's imagination isn't as creative as mine.

I don't see the brackets as overpriced at $85 each, IF they aren't going to break. But any price is too expensive for something with a claimed lifetime warranty that isn't honored.

The Koni solution is sound, but I don't personally like the idea of drilling holes in the chassis. I may just fabricate my own mounts so that I know they're up to the task, and because I need another project I don't have time for.

steveg · May 19, 2020

AH67AH said:
Hey, if that was the actual price then I'd be first in line! But my bank account's imagination isn't as creative as mine.

I don't see the brackets as overpriced at $85 each, IF they aren't going to break. But any price is too expensive for something with a claimed lifetime warranty that isn't honored.

The Koni solution is sound, but I don't personally like the idea of drilling holes in the chassis. I may just fabricate my own mounts so that I know they're up to the task, and because I need another project I don't have time for.

Is the lifetime warranty for the Bilstein shocks or for Udo's pieces? It might just be for the shocks. What does the brochure say?

Looking at your pictures, the upright ripped out of the lower part. I'd think you could fabricate a new bottom out of thicker square tubing and weld the old upright to it with gussets or a reinforcing plate and take it from there.

There are a lot of Healey folks with Udo's kits and yours is the first failure I've heard of. I have several friends with them who engage in spirited driving.

Ask Udo if he'll guarantee the new ones in writing for free replacement if they break.

vette · May 19, 2020

Steve's upper mount from the Cape looks to be thinner metal than the mount that has broken for AH67AH, yet Steve's isn't broken or bent after a whole lot of miles. The only way AH67AH's mount could have broken as shown is from it being jammed or forced or twisted heavily. Shocks under appropriate conditions don't put any more pressure on their mounts than the pressure it takes to close them up. AH67AH's mounting arrangement is not right. You could reinforce that all you want and if it didn't break again it would bend something else.

dougie · May 19, 2020

red57 said:
AH67AH
A different approach is the Koni tube shock kit from the '60s. I have had a set of these for over 20 years (including 15 years vintage racing) and never had a problem with the mountings. Initially I was worried about the strength of the sheet metal for the upper mounts but there has never been a crack.

Koni hasn't made these kits for many years but the fabrication of the mounts is fairly straightforward.

Attached is the installation instruction sheet for the rears - the only thing it doesn't detail is that the lower bracket for the right side is offset to move the shock inboard enough to clear the Ebrake cable and therefore the location of the upper bracket is also moved inward a bit. (I don't have dimensional info or remember exact offset because I modified mine to match the left side and changed my Ebrake cable mount accordingly)
View attachment 63795

I'm not advocating anything here but just showing another way that has been done since the '60s. Down side is it required drilling holes in the bodywork and I completely understand why the other mounting system is attractive to most.

Note to anyone considering making their own mounts to copy the Koni setup shown here: I would be willing to share photos and dimensional info with anyone wanting it, but be aware that Koni quit making this particular shock a few years ago so you would need to find a shock with the length and stroke to work. The Koni rear shock part number is/was 80-1504.

I was lucky and found an original uninstalled kit on ebay 25 years ago - probably not much chance of finding one now.

just food for thought.

Dave

Oh.... Now I know why your were able to blast through T5-A/T5-B at PRW with ease, never missing beat... :encouragement:

AH67AH · May 20, 2020

vette said:
Steve's upper mount from the Cape looks to be thinner metal than the mount that has broken for AH67AH, yet Steve's isn't broken or bent after a whole lot of miles. The only way AH67AH's mount could have broken as shown is from it being jammed or forced or twisted heavily. Shocks under appropriate conditions don't put any more pressure on their mounts than the pressure it takes to close them up. AH67AH's mounting arrangement is not right. You could reinforce that all you want and if it didn't break again it would bend something else.

Those forces can be tremendous. It isn't just the force required to compress the shock, it's the force required to compressed it quickly. The faster the shock is moved, the more force it takes to move it.

All I can say is that they were installed according to the manufacturer's instructions, and used in a normal driving manner. The design simply wasn't up to the task, or perhaps there was a defect. I will be inspecting the other side today to see if there are any signs of stress. Since he has changed the design to make it stronger since this set was made, it seems fair to assume a problem was identified. There are no twisting forces that I can see outside of the normal movement of the axle, which should be minimal.

I appreciate all the comments.

steveg · May 20, 2020

I can vouch for the forces. My original design didn't have the gusset and bent through the axis of the u-bolt holes - as did Cape's design. Gusset bears against axle spring mount box. Drawing in above post is design simplified from actual build - but not built.

Thread starter	Title	Forum	Replies	Date
	TR2/3/3A Broken front shock mount on TR3	Triumph	4	May 23, 2005
D	TR2/3/3A repairing broken hardboard seatback	Triumph	8	Jan 17, 2023
	How to repair broken vent window studs?	Spridgets	1	Jan 17, 2023
M	TR6 1973 TR6 - broken choke cable	Triumph	6	Nov 12, 2021
P	Broken Overdrive Switch in Gear Knob	Austin Healey	14	Jul 25, 2020
T	TR2/3/3A Seeking advice on how to repair TR3 steering wheel broken spoke.	Triumph	8	Nov 12, 2019
K	What is this broken part in my transmission/OD?	Austin Healey	6	Jul 25, 2019
	Broken Spokes	Austin Healey	8	May 9, 2018
H	broken sway bar link - again	Austin Healey	8	Sep 5, 2017
K	TR4/4A Replacing a broken 4A turn signal switch indicator?	Triumph	2	Apr 29, 2017
	General Tech Clutch Fork and Broken Pin	Triumph	8	Dec 27, 2016
	TR4/4A Broken Cylinder Head Stud	Triumph	10	Dec 22, 2016
T	Philosophizing on keeping cars for more decades - prompted by a broken throttle cable	Spridgets	3	Nov 3, 2016
B	wire wheels and broken spokes	Austin Healey	19	Oct 10, 2016
I	TR6 Broken front suspension bracket	Triumph	3	Sep 9, 2016
D	TR4/4A broken trans fork pin	Triumph	14	Aug 21, 2016
	TR4/4A Broken Vertical Link	Triumph	17	Jun 6, 2016
D	BJ 8 Side window broken - Help !!	Austin Healey	9	May 2, 2016
K	TR2/3/3A Broken exhaust manifold TR3b	Triumph	13	Apr 7, 2016
K	TR4/4A Performance Cam=Broken Rings???	Triumph	9	Jan 15, 2016
C	TR6 Broken Throttle Shaft	Triumph	4	Dec 11, 2015
	TR6 '74 TR6 - Broken Top bow	Triumph	1	May 23, 2015
B	TR4/4A TR4A Head off for broken manifold stud - What else to do ?	Triumph	13	Apr 19, 2015
J	Healey 100 -- Broken rocker and bent push rods !!!	Austin Healey	7	Sep 18, 2014
P	BJ 8 broken hood frame screw	Austin Healey	6	Aug 20, 2014
	TR6 '74 Clutch & various broken bits	Triumph	20	Aug 19, 2014
M	Broken off dip stick plastic tube, stuck oil pan, and I think too much...	Spridgets	10	Mar 9, 2014
J	TR2/3/3A Broken pinion gear tooth, I am sad!	Triumph	2	Jul 6, 2013
A	Broken Axle Question?	Spridgets	11	May 1, 2013
	Help with restoring broken aluminum logo badge	Restoration & Tools	6	Apr 10, 2013
J	Need some expertise, broken exhaust maniford	Triumph	9	Dec 10, 2012
	Broken Heater Control Tap [valve]	Austin Healey	9	Oct 25, 2012
K	Anyone experience a broken crosshaft pin....	Triumph	6	Sep 5, 2012
H	broken sway bar link	Austin Healey	13	Aug 27, 2012
K	TR2/3/3A Crossshaft broken taper pin removal? TR3	Triumph	5	Jul 17, 2012
P	broken oil cooler fitting	MG	1	Jun 21, 2012
R	TR2/3/3A TR-3A Rear Leaf Spring Broken	Triumph	3	May 29, 2012
	Points failure - broken cam follower	Austin Healey	3	May 14, 2012
W	TR6 broken bleeder on rear brakes tr6	Triumph	12	Mar 16, 2012
	Three broken spiders later.....	Spridgets	54	Oct 28, 2011
	broken spoke	Austin Healey	12	Aug 23, 2011
V	Help: key broken off in ignition!	Triumph	18	Jul 16, 2011
	Gas Gauge Broken on '58 Bugeye.??	Spridgets	9	Jul 10, 2011
B	High Torque Starter Broken mount	Austin Healey	1	Jun 20, 2011
T	TR4/4A Broken disc wheel stud on TR4A IRS hub.	Triumph	3	Jun 7, 2011
S	TR2/3/3A TR3 clutch pressure problem - not a broken spring!	Triumph	3	May 17, 2011
	Is this sender wire broken??	Spridgets	2	Feb 25, 2011
K	BROKEN ROD BOLT has any body had one?	Triumph	9	Jan 30, 2011
	Help needed...broken exhaust manifold stud	MG	15	Nov 26, 2010
	hood [bonnet] release broken cable	Spridgets	34	Nov 16, 2010

Broken Shock Mounts

Share this page

Freshman Member

Attachments

Senior Member

Yoda

Yoda

Freshman Member

Yoda

Freshman Member

Darth Vader

Jedi Trainee

Yoda

Jedi Knight

Yoda

Jedi Warrior

Yoda

Freshman Member

Yoda

Darth Vader

Luke Skywalker

Freshman Member

Yoda

Similar threads