Rear Telescopic conversion.

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Alec
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Rear Telescopic conversion.

Post by Alec »

Hello all,

this is a little advice for people, who like me, have fitted a telescopic damper conversion, to check the installation.
I was doing some maintenance on my wife's Traveller and I noticed that the cross beam that supports the telescopic dampers was very rusty (I don't know who produced this conversion, by the way). As it was difficult to clean in situ I decided to remove it and was surprised to see extensive cracking of the rear floor adjacent to the left hand chassis rail where the beam is bolted through. The metal was not rusty, but simply cracked through fatigue.
I have now welded all the cracks up and put an additional stiffening bracket on each side to tie the mounting to the rear chassis leg.

Alec
jonathon
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Post by jonathon »

Unfortunately this is a common occurance with this kit and has been for the past 12 years. Yet another example of poor design and lack of either feedback or conscience :( :(

Alec
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Post by Alec »

Hello Jonathon,

I don't remember the actual date of installation but I guess about four years ago. I hadn't heard of any failures, hence my posting to warn others.
Whilst the beam itself is substantial, it is the floor that supports the beam, and in droop is not really that strong. Perhaps the designer had underestimated the weight of the rear axle, especially where there are bumpy roads as we have in our part of Shropshire.

Alec
jonathon
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Post by jonathon »

Yes, the problem you describe is common, we have removed at least a dozen of these kits over the years,and I know of several other traders who have done the same if not more. Perhaps the designer should not be involved with this side of the market as this is quite a fundamental flaw in design :( :-? (no pun intended)

Alec
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Post by Alec »

Hello Jonathan,

the temptation to market performance kits that are bolt on must be very high, as it is a good selling point. 'No welding required'.
This does seem to compromise the installation, however, but will not necessarily become apparent for some time.

Alec
Kevin
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Post by Kevin »

Willie also recently sufferred with the same problem.
Cheers

Kevin
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Willie
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rear teles

Post by Willie »

ALEC, yes I have recently suffered the beam snapping in half at
the nearside top tele pivot. I did not rely on the floor for my fitting
but welded the left and right extremeties to the chassis rails.
Unfortunately the basic design is poor so I have reverted to the
standard dampers ( you soon forget what you are missing, or so I
tell myself)!
Willie
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Alec
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Post by Alec »

Hello Willie,

That takes some doing, if your beam is like mine, it is made of approximately 1\8" thick steel and is a fairly deep 'U' section.

The real way would, I think, is to fabricate and weld in a mounting that puts all the load into the chassis leg.

I'll need to keep an eye on this are and see if my re-inforcement is strong enough.

Alec
Willie
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beam

Post by Willie »

ALEC, yes the beam is thick but at the breakage point on mine
is is quite a shallow 'U' section which is obviously the weak point on
each side. It snapped with a loud crack and although I welded it
up I couldn't trust it any more. If you study JONATHONS remarks
re the rear teles it makes sense that the only way to get a reliable
and efficient set-up is to pass the telescopics up through the boot floor
into turrets. If you check the available movement on the original
dampers then the only way to allow an equivalent movement on a
telescopic set-up is to go through the boot floor.
Willie
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Alec
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Post by Alec »

Hello Willie,

yes, I agree, but that means new dampers as well as the kit ones would be too short. As I said I'll just keep an eye on my present set up. As with many things, strengthening one area exposes a weakness in an other area.

Alec
Stig
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Post by Stig »

Not encouraging anyone to point fingers here, but... I fitted the Grumpy's rear tele kit a few years ago - should I be worried?

I didn't see any cracking t'other week when I was changing the rear spring bushes (poly bushes as soooo much easier to fit!) but then I didn't take the beam off.
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grumpys

Post by Willie »

STIG, since Grumpys is now out of business it makes no odds.
My snapped top beam was on the Owen Burton kit, I have no idea
how robust the Grumpys item is. The fact that you say' I didn't
take the beam off' suggests that it is only bolted to the boot floor??
This is likely to flex and eventually crack as ALEC found out.
Willie
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Alec
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Post by Alec »

Hello Stig,

the cracking was not obvious from below although I wasn't really looking I suppose. I only noticed it when I went inside to unbolt the beam. It's worth a very close look especially as it is probably covered in road muck.

Alec
Stig
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Post by Stig »

Hmm, not that easy to see from above as it's a Traveller, not a saloon. I guess I'll have to take the load area floor panels off and have a look. I'm guessing the Traveller's floor is exactly the same as a saloon?

Ah well, I need to get the welder out to the spring mount anyway when I get a free weekend (and the welder back from my brother)... Dontcha just love lying under a car wielding a grinder? Er, no. I don't really. Still, "needs must when the devil vomits into your kettle" as Mr. Blackadder used to say.
Alec
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Post by Alec »

Hello Stig,

my wife's Morris is a Traveller also so yes the floor had to come out.

Alec
Onne
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Post by Onne »

I'd better check my Grumpy's set up too then. As soon as I get her back that is
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Post by bigginger »

Aha! I remember commenting that your rear shocks were "weird" - didn't know they were Grumpys - just practically horizontal...
Alec
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Post by Alec »

Hello Onne, Andrew,

"just practically horizontal.." surely that can't work effectively?

The ones on my wife's car are vertical and close to the spring , as I would expect.

Alec
Stig
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Post by Stig »

Yeah, the Grumpy's kit has them at about 45 degrees. Supposedly gives improved lateral location (fair enough) but would only have 70% of the vertical damping I spoze. Damping's perfectly adequate though.
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Post by bmcecosse »

If at 45 degrees then only 50 % of possible damping ! Dampers can never locate anything - they only 'damp' - it's a con trick.
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