4 post Bradbury liftmaster dol starter

Welshgixxer · Feb 12, 2022

Hi all

From the outset I'm not in an electrician. I am posting here because I'm thinking the subject matter is quite specific and will prob require some historic knowledge/ experience - I'm hoping someone will allow me to benefit from their knowledge.

I am converting a Bradbury 4 post lift (a variation of a liftmaster 735, which I think is a mk1/2) from 3 to single phase - single direction motor.

The issue I have is with the Dol starter. I want to replace the 415v original with a 230v dol starter with overload. The original dols is housed within the oil reservoir and the (dols') on/off buttons are 'pushed' via a mechanical rod & linkage setup connected to the up/down lever on the main post.

I'm thinking I need to either retain the original dol metal enclosure, replacing it's innards OR replace the entire box.

Simplest would appear to be to retain the original enclosure - thus retaining the mechanical on/off linkage - problem would be the successful marriage of the enclosure on/off buttons with the new internals.

Anyone thoughts/ experience/ solutions of/ for this scenario more than gratefully received.

photos attached (hopefully)-

Welshgixxer · Feb 20, 2022

Welshgixxer said:
Bri

Hope you don't mind - electrically lift works fine. All posts are plumb and ramp level.
Without extra load ramp reaches chest level fine but then seems to struggle - not smooth - slow and hesitant I.e. rise/pause/rise/pause - not jumpy but as if needing to build pressure before continuing. It lowers without resistance - so I am thinking pump/ ram seals need replacing - make sense.
Tried attaching vid but too large

Si

Photo of (fresh) oil reservoir - looks aerated to me - indicate anything? - all new to me

brianmoooore · Feb 20, 2022

Sounds like either not enough oil in the reservoir or something wrong with the pick up.
Ram seal wouldn't cause this, until enough oil had leaked out to cause problems

Welshgixxer · Feb 20, 2022

brianmoooore said:
Sounds like either not enough oil in the reservoir or something wrong with the pick up.
Ram seal wouldn't cause this, until enough oil had leaked out to cause problems

Cheers Bri, came to same conclusion after posting to you. Gemco advised 15l but having checking Bradbury manual - should be 22. Will let lie for a bit, top up and cross fingers for easy fix - lucky I removed Res cover as I had thought mechanical interference on main post and been grinding column to allow free movement - (evidence of historical roller to post contact)

brianmoooore · Feb 20, 2022

Mine has a oil drain pipe back to the sump, connected into the ram housing, just above the top limit of the seal. Every time you raise the ramp fully up, any oil that has passed the seal is returned to the sump.
Does yours have this feature?

Welshgixxer · Feb 20, 2022

brianmoooore said:
Mine has a oil drain pipe back to the sump, connected into the ram housing, just above the top limit of the seal. Every time you raise the ramp fully up, any oil that has passed the seal is returned to the sump.
Does yours have this feature?

Into reservoir from pipe (green arrow) through rectangular cut out (green arrow).
The manual I have is for mk1 - quite basic (few pages) - happy to send you a copy if any use.

Welshgixxer · Feb 20, 2022

brianmoooore said:
Mine has a oil drain pipe back to the sump, connected into the ram housing, just above the top limit of the seal. Every time you raise the ramp fully up, any oil that has passed the seal is returned to the sump.
Does yours have this feature?

Enters reservoir through pipe (green arrow) through rectangular cut out (blue arrow).

Bradbury manual (v basic) any use to you?

Welshgixxer · Feb 20, 2022

It works. Celebratory cuppa

RAmadu · May 26, 2022

Welshgixxer said:
It works. Celebratory cuppa

We have just put up a used Bradbury 735 MK1, came with no instructions. Our Lube tank is a big square tank, has the motor inside . Can you tell me how much hydraulic oil to put in? Glad you got yours going. We also had to change motor from 3 phase to single, using capacitors? thanks,

Welshgixxer · May 27, 2022

RAmadu said:
We have just put up a used Bradbury 735 MK1, came with no instructions. Our Lube tank is a big square tank, has the motor inside . Can you tell me how much hydraulic oil to put in? Glad you got yours going. We also had to change motor from 3 phase to single, using capacitors? thanks,

Manual states 22l - I found out that 15l insufficient - 20l worked fine (lucky as I bought a 20l tub)

brianmoooore · May 27, 2022

If you hear the pump start to cavitate when the ramp is nearly fully up, add a bit more. Nothing critical about it.

RAmadu · May 27, 2022

Thanks for the Help. . We are on solar power, Generator backup. And the used hoist came with no manual, and already dismantled,

brianmoooore · May 27, 2022

Mine came with no manual, already dismantled and under three feet of floodwater.

muddyboots · Aug 6, 2023

Welshgixxer said:
Into reservoir from pipe (green arrow) through rectangular cut out (green arrow).
The manual I have is for mk1 - quite basic (few pages) - happy to send you a copy if any use.

c20loon · Mar 23, 2024

Welshgixxer said:
Into reservoir from pipe (green arrow) through rectangular cut out (green arrow).
The manual I have is for mk1 - quite basic (few pages) - happy to send you a copy if any use.

Hi Welshgixxer, recently aquired a mk1 in bits and trying to peice it back together, any chance you still have a copy of the manual? Have been scouring the net for several weeks on and off trying to find one but no luck this far. Many thanks in advance