I didn't get it up often enough .....

[Sproket]

After having a problem with my Kojack scissor jack a few weeks ago, when trying to lift the van up a smidge to remove the axle stands, the dammed thing kept lowering very slightly, i initially thought that i had not fully tightened the release screw properly, but no joy, so after quite a few goes i managed to get the axle stands out & the van wheels on the floor, I then took the jack apart thinking that it would need new seals fitting, but to my horror the damage to the cylinder wall was irreparable where it looked as though the piston had tipped & dug into the wall causing a rather large gouge, I took some photos & e-mailed them to purple line to see what they would / could do, as this jack has only been used about ten times in the last four years to put the van on & off of the axle stands..........

The vans MTPLM is 1600kg, so 800kg per wheel is well within the saftey margin of the 1000kg jack

This is the piston with damage to the lower collar bent in towards the seal

Damage in the cylinder wall

Looking from other end

If I had been using it every month to level the van up, or put the silly Al-ko wheel lock on, this problem would have shown up a lot earlier,

Credit to Purple line as they told me it was out of warranty, but they would do me a new kojack light at a reduced cost, that I accepted & the new one including new brackets arrived today.

 

[ProfJohnL]

Hello Sprocket,
Under SoGA the offer you have is probably proportionate considering the age of the product.

Looking at the photos it is clear the piston has become missaligned and teh piston head has contacted the side of the culinder with some considerable force. This should not happen in a closed system, so either the system was faulty at manufacture, or it has suffered some damage during its life.
Assuming you have not damaged it, then it leaves as being faulty at the point of sale. The difficulty is that you would need to prove it to be able to get it fully replaced under SoGA..
Even so that seems a very unreasonable short duty life for such a product, and frankly I am apalled that Purple Line have not offerd a complete FOC replacment as a complete gesture of good will.

.

 

[Sproket]

Hello Prof,
Thanks for your views.
I think you have it the nail on the head with faulty at manufacture #2.
Have read over the years about them leaking oil, so for me to do a re-seal would not have been a problem.
When I return to work I willl get the piston & cylinder PMI inspected to find out what sort of monkey metal they are made of, with a view to getting them re-made from something more suitable.

 

[Martin24]

This post was edited because it contained rather too much information Martin

Parksy (Moderator)

 

[Stephen1956]

I had a Kojack Lite and it would suddenly colapse spewing oil from the seals it started the second time I used it but did not do it every time,I decided it was to much of a lottery so returned it and got a full refund and purchased a Alko side lift jack.

 

[graham_somersham]

The problem with the Kojacks are they are a good idea poorly implemented by not using top quality materials. I guess the jacks are made for a few pounds in some Chinese factory who are not too worried about the materials used or the tolerances between components. I have a bottle jack for my truck and it is of a similar size to the Kojack but way superior in manufacture and it feels right when in use as opposed to the Kojack that gives me concerns each time I put it under the caravan. I now carry a thick steel plate to place the Kojack on as I believe anything other than a perfectly straight lift will damage the jack and lead to failure.

While idiots like me continue to purchase low grade products others will continue to manufacture them. I'm sure that there must be a BS or ISO standard for such devices and it would be interesting to read what it says.

 

[ProfJohnL]

A quick search has failed to uncover any specific UK/EU regulations for vehicle jacks. this does not preclude any regs, just that I have not found them.

However the UK HSE has published teh following:-

http://www.hse.gov.uk/lau/lacs/90-4.htm
As most jacks will be supplied as part of the vehicle, (don't forget a caravan is a vehicle but not a 'motor vehicle')s the majority of vehicle design is covered by type approvals. These will almost certainly require the design and manufacture of a vehicle for sale in the EU to be conducted within management system compliant with ISO 9001 or equivalent.

OEM or after sales suppliers may not be bound by the same requirements.

Its worth bearing in mind that the average car jack only gets very little use, so its design brief may not include 100+ operations

I did find some documents from Australia which specifically relate to vehicle jacks. You may find these interesting:-

http://www.consumer.tas.gov.au/__data/assets/pdf_file/0008/108476/RIS_Vehicle_Jacks_DRAFT_July_2008.pdf
http://www.productsafety.gov.au/content/index.phtml/itemId/974838#toc7