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Sideroad
14th December 2010, 08:14 AM
I have recently fitted para springs and bought Rocky Mountain shocks from FWD here in Brisbane. The shock came with check straps and I have fitted them with the ends of each strap flush with the to of the brackets they are normally fixed to. My only concern is whether they are the correct length from factory or am I meant to cut them to a specific length.
Does any one out there have a simple test to see if the straps are the correct length other then just taking it out bush? (not yet ready for the road/bush)
Tis on my '68 109 2A

wozapinin
14th December 2010, 09:07 AM
I think those straps are to stop you're shocks over extending. Measuring the extended length of the shocks plus axle housing and subtract a bit should be the length. I made some brackets and spliced some rope, 2 each side, on mine:o.

isuzurover
14th December 2010, 09:21 AM
Do yourself a favour and throw the check straps in the bin. If your shocks aren't strong enough to limit wheel travel then they shuld be replaced with better items.

What do you think limits wheel travel on coillers???

I threw my check straps in the bin when I bought my IIA back in 1993. I have more wheel travel than most (indeed more than most para setups I have seen), my landie is used offroad regularly, and in all those years of hard use I have only ever broken one (front!) shock. I still have the riginal (1968) front shocks - rebuilt a couple of times though!

https://www.aulro.com/afvb/

JDNSW
14th December 2010, 09:24 AM
The check straps are solely to protect the shock absorbers.

You can test the length by simply jacking the chassis (preferably on one side) until the wheel lifts off the ground. (a perhaps easier way of doing it is to jack up one wheel, put a stand under the chassis, remove the wheel, and lower the axle, to give the same effect of a fully extended suspension on one corner) The check strap should then be tight rather than the shock absorber taking the load. If desired you can check how much extra movement is available on the shock absorber by disconnecting one end and extending it.

John

Rainer
14th December 2010, 09:32 AM
Do yourself a favour and throw the check straps in the bin. If your shocks aren't strong enough to limit wheel travel then they shuld be replaced with better items.

What do you think limits wheel travel on coillers???

I threw my check straps in the bin when I bought my IIA back in 1993. I have more wheel travel than most (indeed more than most para setups I have seen), my landie is used offroad regularly, and in all those years of hard use I have only ever broken one (front!) shock. I still have the riginal (1968) front shocks - rebuilt a couple of times though!



Hi,

Interesting. May I ask what is the maximum travel of your shock absorbers ?

The Land Rover only had checkstarps for the rear Axle as it looks like the front leaf springs never extended enough in order to damage the front Shock absorbers.

I just fitted some OME in the rear with a maximum travel of 470mm. Do you think I can take the check straps off from my rear axle ?

Thanks and regards Rainer

https://www.aulro.com/afvb/images/imported/2010/12/1088.jpg

NiteMare
14th December 2010, 09:37 AM
check straps are only really to protect the shocks "without" internal buffers (original oil filled shocks) from over extending, if you have modern gas shocks i'd hazard a guess that you "have" the internal buffers...

on saying that i have para's fitted and run on "heavy duty 109" front shocks all round (88" Bitsa), i haven't broken them yet and they seem to cope with damping the para's quite well

isuzurover
14th December 2010, 09:56 AM
Hi,

Interesting. May I ask what is the maximum travel of your shock absorbers ?

The Land Rover only had checkstarps for the rear Axle as it looks like the front leaf springs never extended enough in order to damage the front Shock absorbers.

I just fitted some OME in the rear with a maximum travel of 470mm. Do you think I can take the check straps off from my rear axle ?

Thanks and regards Rainer


I can't remember what the max travel of my shocks is. Mine is a military landie, so I have extended shackles and spring hangers, and longer shocks. I rant the OEM shocks for a while, and still run them on the front, but with RRC OME shocks on the rear now.

I hit maximum travel on the fronts on both the up-travel and down. The longer rears don't get fully extended often - unless I have a reasonable load on. The old rears did get extended to full travel regularly and never failed.

So yes, as I mentioned above, I think anyone with a series landie should be able to take their check straps off without issues. Most landies will very rarely max out their shocks, but even if you did on a regular basis the shocks should hold up fine.

I forgot to add, my father's IIA has no check straps either, and I set the springs on that up to travel well also. He has never broken a shock.


EDIT: Also - when I broke a front shock, I removed the shock, and drove for 2 days of hard offroading and then 300 km home with no shock on one corner. I could barely notice the difference if at all. On multi-leaf semi elliptic suspensions, shocks don't do a great deal, as the leaves have a lot of inherent damping (i.e. unless driving on very bad roads/corrugations they don't do much). Many trucks do not have shocks at all (if they have enough leaves in their spring packs).

So - there is always a very slight possibility you may break a shock, but if you do it won't be a big deal.

On a coiller however it feels like you are driving a pogo stick...

Sideroad
14th December 2010, 09:37 PM
I never did have the straps with the old springs and when removing the old shocks I found none of them did anything as they were all blown. :) (I could just tip them upside down and they would compress)
The 109 handled like a race car on corners and the springs only moved when loaded with 1/2 tonne or more.
I guess with that many leaves the shocks don't do much. Now I have the Paras and I think the shocks will be needed more.(I have only used it for one weekend on the beach since installed as I forgot to pay rego and I now have to have a Safety cert done) :(
Is there much risk of over extending Rockie Mountain shocks? I have no idea on what system they are.

Sideroad
14th December 2010, 09:39 PM
I have seen this pic of your machine before and marveled at the cross articulation. Is the major difference from norm, paras and a military chassis? Or have you done more? Thanks for the advice.


Do yourself a favour and throw the check straps in the bin. If your shocks aren't strong enough to limit wheel travel then they shuld be replaced with better items.

What do you think limits wheel travel on coillers???

I threw my check straps in the bin when I bought my IIA back in 1993. I have more wheel travel than most (indeed more than most para setups I have seen), my landie is used offroad regularly, and in all those years of hard use I have only ever broken one (front!) shock. I still have the riginal (1968) front shocks - rebuilt a couple of times though!

https://www.aulro.com/afvb/

isuzurover
14th December 2010, 09:51 PM
I have seen this pic of your machine before and marveled at the cross articulation. Is the major difference from norm, paras and a military chassis? Or have you done more? Thanks for the advice.

Thanks. However, I DON'T have paras. I have modified semi elliptics which IME give better wheel travel than off the shelf paras - I have posted the mods I did in a thread here. Apart from that, mil hangers and shackles, modified front bump stops and modified rear shocks.

Paras have less interleaf friction than semi-elliptics, which make them more like coils for small bumps, but the fat leaves don't flex that well overall. Much better than OEM though, because as you have said you usually need 1/2 tonne to get the standard springs to flex.

Paras do need shocks slightly more then SEs do, however paras don't need check straps any more than SEs do.

dullbird
15th December 2010, 05:59 PM
you can throw the check straps in my bin if you like:D.....I'm going for the look then then application :lol2:

Rainer
16th December 2010, 01:59 AM
check straps are only really to protect the shocks "without" internal buffers (original oil filled shocks) from over extending, if you have modern gas shocks i'd hazard a guess that you "have" the internal buffers...

on saying that i have para's fitted and run on "heavy duty 109" front shocks all round (88" Bitsa), i haven't broken them yet and they seem to cope with damping the para's quite well


Hi,

Well as I wrote before I have OME (Old Man Emu) Nitrocharger shock absorbers installed which I think are Gas shocks.

I contacted the ARB technical support in USA and got as an answer that if the springs do not fully extend the shock absorbers it is OK, but if Yes then I should use limiting straps or in this case axle check straps as they are called in Land Rover Serie 2 language.

Here is the exact text of the e-mail I got


Hi Rainer,

The shock should be the limiting factor of suspension extension during slow speed articulation. There should be enough range of motion in the shock to not be the limiting factor of extension during high speed travel (the suspension generally travels less distance at higher speeds than traversing larger, slow speed obstacles). Assuming the shocks have the correct amount of travel so as to not “top out” at higher speeds the limiting straps should not be necessary.

Best Regards,

*name deleted by me*

ARB Tech

regards Rainer (Mexico)