Winching with a Hi-Lift Jack
Most 4x4ers carries a
hi-lift jack when going on trails and overlanding. It is quite a versatile tool but it gets primarily used for
jacking. However with little effort,
the jack can be turned into a cost effective winch.
It is however not a simple
case of throwing some straps and chains around and now you can winch yourself
out of any situation. Due to the very
nature of using a hi-lift as a winch one gets to work right in the danger
area. For this reason, care must be taken
to use correctly rated items.
Use this document as a guide
when putting your own equipment together.
Components
What tools are required for
assembly?
Field Preparation
Assembly
Fitting the grab chains
Remove the base plate from
the hi-lift jack by pulling out the pin at the base. Enlarge the bottom hole of
the jack bar by filing off 1mm on the edges the furthest apart. Test to see if the hammerlock slides
through. Do not modify the hammerlock
to allow for easier fitment. Attach
this hammerlock to the 300mm chain.
Take care to use the load pin retaining bushing. On the far end of the chain fit the grab
hook. Both roll pins must be
inserted. Fit the grab hook to the
other 300mm chain. Secure the chain
using a hammerlock to the jack saddle.
Preparing the pull chain
Secure the grab hook and the
hammerlock to each end of the chain.
Field Assembly
Remove the jack base plate.
Fasten the grab hooks to the jack using a light hammer to tap the load pin
through the retaining bush. For easy removal loosen the hammerlock load pin
using the hammer with a punch. NEVER
operate the hammerlocks without the retaining bush on the load pin.
Operation
Use an appropriate anchor
for the winching operation. (EG another
vehicle or tree) In this exercise a
pull strap (not kinetic) was used around a sturdy tree. The loops off the pullstrap are secured with
a bow shackle to the clamping end of the hi-lift jack. The bow shackle pin goes through the hole of
the clamp attachment. Tighten the pin completely
and then give it a quarter turn back.
Attach the pull chain in a secure manner to the stricken vehicle. Use the grab hook to determine the
appropriate length. If not possible use
the hammerlock end of the chain with a rated 3.25ton d-shackle to fasten the
hammerlock to the vehicle recovery point.
Step 1: Unlock the jack saddle,
move it to the foot end and lock the saddle in place. Secure the saddle grab chain to the pull chain. Take up the slack by pulling the saddle up
the jacking bar until it clicks in place.
For safety purposes hook the jack bar grab chain to the pull chain.
Step 2: Start jacking until
the saddle reach the top end of the jacking bar.
Step 3: Secure the jack foot
grab chain to the pull chain as far as what it can reach in the direction of
the stricken vehicle. Unlock the
saddle. Carefully reverse-jack until
the full load sits on the jack foot grab chain. The saddle will become loose on the jacking bar and can be moved
to the bottom end to start the process again. (Step 1)
Safety
General Design and Safety
Considerations
First you need ask yourself, when you overload the
system, what do you want to break. Preferably something close to you, I know it
sounds wrong, but I'll explain. When something breaks at the end of the chain
3m or 4m away while working with the jack as a winch, the chain and what ever
is attached to it comes flying towards you and it could be fatal. On the jack
the weakest points are the shearbolt and the toe of the jack, in the worst case
and more likely, the toe will break. Hopefully because you're standing at the
point of breakage, everything will fly away from you, but there are no
guarantees, but it is safer this way. That is why it is important to keep
bystanders far way and NEVER step on the tensioned chain as it could affect the
ratings. The jack is rated to pull 2267kg in the winch configuration and your
other attachments should be of a higher rating (also recommended by hi-lift).
The next rating up on the jack for the chain is 10mm Herc-alloy 800. The chain
as well as all attachments are rated at 3.2tons with a safety factor of 4. It
is very important to use chain that is correctly rated. Not all 10mm chains are
rated at 3.2tons, some low grade 10mm chain can only handle 1ton. Herc-alloy800
chain also makes allowance for wear, which means the chain will handle its
rated load as long as the chain hasn't worn to less than 8.5mm diameter
anywhere. When attaching the grab hook onto the chain, it will look like the
chain gets abnormally stressed, but the chain and hook is designed to handle it
and still keep to the 3.2ton rating. Due the size of the chain, and difficulty
attaching it to the jack, it was decided that the best way to attach the chain
was with a hammerlok coupling (also recommended by Haggie). The hammerlock does
not fit through the slot in the jack and the slot has to be slightly enlarged.
It is important to rather modify the jack's slot than the hammerlok, as you'll
be modifying the weakest point on the hammerlok to make it fit through. Any
other method of attaching a chain would have meant that the existing slot of
about 14x17.5mm has to be modified to take a 20mm pin and because the pitch of
the slots are 20mm, you will en up with a hole of about 20mmx34mm and the
bottom end of the jack. Thus, it is important to only modify the hole as little
as possible, just enough to squeeze through the hammerlok.
Ratings
10mm Chevlok Cradle Grab
Hook (McKinnon Chain)
10mm Hammerlock (McKinnon
Chain)
10mm Herc-Alloy Chain 800
48” Hi-Lift
Costs
All
prices are VAT exclusive
Supplier
Special thanks to Barto De
Koning for helping with the design and safety ratings of the equipment.
The author takes no
responsibility for information contained in this document.
Copyright: Morne Stevens ©