Mr Whippy
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| posted on 3/2/14 at 12:49 AM |
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Warning Balljoints Explode! – what not to do...
Thought I’d let you lot know what happened today, after 25 years fixing rusty old cars I’ve never had this occur and tbh I was very lucky I wasn’t
hurt.
So what happened? Well the old landys track rod ends were needing swapped out unfortunately they were (still are) very much rusted solid to the rod.
As usual I got out the blow torches and started heating the rod where the thread goes in. As the balljoints were to be scrapped I just let it get
toasted. All was going to plan so left it heating up on some axle stands and was just going out the garage door when there was a roaring noise, looked
back and there was a jet of orange flame shooting out the joint, hmm interesting oh well that’ll help heat the sucker up!
Fortunately I left it alone and went out the garage, 10 seconds later there was an almightly BANG! Followed by a crash what the hell was that!!
Opps, looks like the balljoint just blew up...steering link was 2 ft from where it was on the now knocked over axle stands, blow torches are on their
sides and the balljoint seems to now be empty 
Investigation: I think something inside the joint, maybe a plastic part ignited and over pressurised the space above the ball bulging the cap till it
blasted off (I haven’t found that part, it could be in orbit...) seeing that the caps are about 2mm thick that must have been quite a force to remove
it, kinda dangerously too especially when I normally am sitting right next to it holding the blow torch.
Oh well there you go, a good example of what not to do when you’re having fun with rusty stuff, hopefully it will not happen to you now. Some pics of
what's left of that one and what the other one looks like.
[Edited on 3/2/14 by Mr Whippy]
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Davey D
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| posted on 3/2/14 at 06:57 AM |
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like you say, it was probably something plastic, or some grease inside the joint that when it got hot started to melt/ignite then the gasses
released expanded, and due to being in a tightly enclosed metal joint pressurised, and exploded the end off. Would never have expected that to happen!
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Daddylonglegs
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| posted on 3/2/14 at 07:29 AM |
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Chuffin' 'ell!!!
Thankfully you weren't near the sucker when it blew!
My money is on the grease inside boiling and then the end cap had no chance! You'll probably find the end cap buried in whatever the ball hit!
It looks like the Midget is winning at the moment......
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Ivan
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| posted on 3/2/14 at 07:52 AM |
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Wow - lucky you weren't there - reminds me of my Dad working on a single engined diesel pump on the farm one day because the decompression valve
wasn't working, so it was difficult to start. He fixed it and whilst he was crouched on his heels operating it and told my Mom to give the motor
a crank - she did so getting a good speed up, he released the valve and it fired blowing the improperly installed valve right out and into his
forehead - he fell over backwards and when he got up had the valve protruding from his sinuses with snot, blood and air bubbling around it as he
breathed, it was a case of doctor heal thy-self - he pulled it out and bandaged his head and Mom drove him to the nearest hospital, some 50 miles away
on poor gravel roads, he was the only doctor in the district so there was no other help available.
Moral of the story in both cases is take care out there - you never know what can go wrong.
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kipper
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| posted on 3/2/14 at 08:13 AM |
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I wouldn't bother looking for the cap mate ,your gonna need new track rod ends.
Denis.
Where did that go?
<<<<
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thetankwad
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| posted on 3/2/14 at 10:07 AM |
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Yikes! Lucky you weren't on the move. I have heard stories of them exploding on the move from folk, usually to the utter destruction of
everything on that side of the car!
Also, looks like you are near me! I've seen the bluebird out and about in Aberdeen, will give you a flash and a wave next time i see you...
I'm usually in my wee MX5.
--Lets get down to Business!--
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Dick Axtell
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| posted on 3/2/14 at 10:17 AM |
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Exploding Plastic - Yes!!
Reminds me of an incident during my early days, working on Monotube (pressurised) dampers. Had to conduct endurance tests on dampers fitted with
floating pistons made from new plastic material. (Floating piston = barrier between gas chamber & damping oil). These dampers were fitted with
water cooling jackets, to maintain steady temperature.
Unfortunately, there was an unannounced interruption in our water supply. Damper temperatures rose rapidly - it seems!! Discovered this only after
they all went BANG!!! Nuffink left of neither experimental floating pistons, nor damping oil.
We reckon the plastic pistons initiated the pressure rise, and the damping oil diesel-ed, because there was no oil residue on the test rig. So plastic
definitely can cause ignition explosions when heated to extreme.
Good job no-one was injured in your case.
Work-in-Progress: Changed to Zetec + T9. Still trying!!
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MikeRJ
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| posted on 3/2/14 at 10:44 AM |
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quote:
Originally posted by Dick Axtell
We reckon the plastic pistons initiated the pressure rise, and the damping oil diesel-ed, because there was no oil residue on the test rig. So plastic
definitely can cause ignition explosions when heated to extreme.
Where would the oxygen for combustion come from? I guess if the damper rod seals had melted it could draw air in?
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Thetom
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| posted on 3/2/14 at 11:59 AM |
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I replaced mine (steering bars) with Sumo bars, you then have a solid bar with a spanner flat instead of the stupid split tube design that lets all
the crud into every turn of the thread. Joint is locked up with a lock nut instead of the tube clamps.
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nick205
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| posted on 3/2/14 at 12:20 PM |
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^^^ That looks a better solution all round!
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Mr Whippy
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| posted on 3/2/14 at 12:40 PM |
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quote:
Originally posted by Thetom
I replaced mine (steering bars) with Sumo bars, you then have a solid bar with a spanner flat instead of the stupid split tube design that lets all
the crud into every turn of the thread. Joint is locked up with a lock nut instead of the tube clamps.
^
Agreed, I've decided to scrap the old links and get heavy duty ones instead. Like you say the splt tube design is flawed.
[Edited on 3/2/14 by Mr Whippy]
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Dick Axtell
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| posted on 3/2/14 at 03:44 PM |
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quote:
Originally posted by MikeRJ
quote:
Originally posted by Dick Axtell
We reckon the plastic pistons initiated the pressure rise, and the damping oil diesel-ed, because there was no oil residue on the test rig. So plastic
definitely can cause ignition explosions when heated to extreme.
Where would the oxygen for combustion come from? I guess if the damper rod seals had melted it could draw air in?
As I recall, these test dampers had been assembled in the workshop and charged with air, and not the usual oxygen-free nitrogen. afterwards, we had
charging collars made, to allow units to be built with ready-welded tube assemblies, but filled with O2-free nitrogen.
[Edited on 3/2/14 by Dick Axtell]
Work-in-Progress: Changed to Zetec + T9. Still trying!!
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MikeRJ
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| posted on 5/2/14 at 04:59 PM |
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quote:
Originally posted by Thetom
I replaced mine (steering bars) with Sumo bars, you then have a solid bar with a spanner flat instead of the stupid split tube design that lets all
the crud into every turn of the thread. Joint is locked up with a lock nut instead of the tube clamps.
The only disadvantage is that a locknut can apply a considerable load to a stress raiser (i.e. the thread) which doesn't happen with a split
tube and clamp. Obviously not a problem providing the threaded section is strong enough to start with.
[Edited on 5/2/14 by MikeRJ]
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Thetom
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| posted on 6/2/14 at 08:50 AM |
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quote:
Originally posted by MikeRJThe only disadvantage is that a locknut can apply a considerable load to a stress raiser (i.e. the thread)
which doesn't happen with a split tube and clamp. Obviously not a problem providing the threaded section is strong enough to start with.
[Edited on 5/2/14 by MikeRJ]
Landrovers use imperial threads; its a fine pitch and from memory, id say its probably at least a 3/4" diameter with probably about
1-1/2"of thread engaged so id be fairly confident I don't need my calculator to be sure it can take any load I can put on with a spanner
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CompoSimmonite
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| posted on 10/2/14 at 11:45 AM |
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quote:
Originally posted by Ivan
Wow - lucky you weren't there - reminds me of my Dad working on a single engined diesel pump on the farm one day because the decompression valve
wasn't working, so it was difficult to start. He fixed it and whilst he was crouched on his heels operating it and told my Mom to give the motor
a crank - she did so getting a good speed up, he released the valve and it fired blowing the improperly installed valve right out and into his
forehead - he fell over backwards and when he got up had the valve protruding from his sinuses with snot, blood and air bubbling around it as he
breathed, it was a case of doctor heal thy-self - he pulled it out and bandaged his head and Mom drove him to the nearest hospital, some 50 miles away
on poor gravel roads, he was the only doctor in the district so there was no other help available.
Moral of the story in both cases is take care out there - you never know what can go wrong.
Mate and I were trying to get a big commercial ride on mower he'd bought running without success. I removed the plug and told him to wind it
over on the starter so I could check it was sparking. Of course the cylinder was full of unburnt fuel that got pushed out all over me at the same time
the plug sparked. Guess what - I was engulfed in ball of flame. Only a split second and seeing I was wearing shorts / tee shirt all exposed hairs
burnt off but otherwise uninjured. No excuse - my own stupid fault 
Paul H
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