Jump to content

Smaller PAS pump pully


Recommended Posts

I run full hydraulic steering with the normal pas pump, but I would like to a bit more "oil-flow" (is this correct english). To get this I would like to install a smaller pully on the pump, but are they available "off the shelf"?



Link to comment
Share on other sites

I think there is a mod where a hole on the inlet / outlet of the standard pump is made bigger for more flow. I don't know the details though and not sure if overheating the PS circuit would be an issue requiring a cooler?

Problem with going to a much smaller pulley may mean the belt may start to slip under max load as there's less contact area.

Link to comment
Share on other sites

A smaller pulley on the pump will not make any difference to the flow rate- the output flow is constant pretty much regardless of the speed at which it turns.

You will need to change the pump to a higher flowrate one- Possibly a ZF74 which you can get from Allan at www.4x4winches.com new for about £135 +vat- he sometimes has good second hand ones as well. They are rated at 120bar and 13L/min (I believe that the flow is actually less than this going by the two on my truck). Or if you take a look at one on a scrap 7 series BMW you should find they they will be pretty similar...


Link to comment
Share on other sites

Looks interesting, decided to compare the spec to the ZF74:

PSC Pump:

Flow: 4.5 gpm (=17 litres/min)

Pres: 1600psi (=110bar)

ZF74 Pump:

Flow: 12.5L/min (=3.3gpm)

Pres: 120bar (=1740psi)

(using US gallons in the conversion)

Are the mountings fairly standard between different pumps or would it need custom brackets for LR engines?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

We use cookies to ensure you get the best experience. By using our website you agree to our Cookie Policy