Suspension arms jack pad

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Mr Spigot
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Suspension arms jack pad

Post by Mr Spigot »

The workshop manual recommends the use of a 'special jack pad' when jacking up the front suspension arms, to prevent the jack from slipping. Is such a pad available or is there a practical alternative, other than the block of wood I have been using for many years?!
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Jack pad.PNG
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1960 2 door 'Mostyn' - 1275 Midget engine - WOI 577 - owned since 1990
1952 MM convertible 'Mawdie' - 918 SV engine - MWD 305 - owned since 2023
philthehill
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Re: Suspension arms jack pad

Post by philthehill »

The only jacking safety pad/anti slip bracket I am aware of is that fitted to early Post Office vehicles. It was basically a 'U' clamp fitted around the lower suspension arms. The 'U' clamp stopped the jack slipping down the lower suspension arms.
Easily replicated using a suitable exhaust 'U' clamp.

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geoberni
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Re: Suspension arms jack pad

Post by geoberni »

I'd never heard of the Plate Phil spoke of, so I looked it up.
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Jacking Plate.JPG
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For some reason the person responsible decided to give the nomenclature of Plate - Jacking Bracket - RH and the Quantity 2.... :-?

I wonder if anyone ever spent a while looking for Plate - Jacking Bracket - LH :lol:
Basil the 1955 series II

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Mr Spigot
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Re: Suspension arms jack pad

Post by Mr Spigot »

Thanks Phil and geoberni. Now it is mentioned, I recall this being shown in the old MMOC 'Technical Tips' book published sometime in the 1980s. Seems like a nice cheap and simple solution. I will have to find my old copy!
1960 2 door 'Mostyn' - 1275 Midget engine - WOI 577 - owned since 1990
1952 MM convertible 'Mawdie' - 918 SV engine - MWD 305 - owned since 2023
myoldjalopy
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Re: Suspension arms jack pad

Post by myoldjalopy »

Here you go:
2025-10-03 16.32.38.jpg
2025-10-03 16.32.38.jpg (548.93 KiB) Viewed 3572 times
Dunno why its sideways.............
les
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Re: Suspension arms jack pad

Post by les »

That’s interesting, I had a pair of these plates, however I fitted them with the plate underneath.

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svenedin
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Re: Suspension arms jack pad

Post by svenedin »

Great idea. Handy but I do keep a suitable piece of wood in the boot so that I can jack under the front chassis rail anyway. This would be useful when doing suspension work though.

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1969 1098cc Convertible “Xavier” which I have owned since 1989.

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Re: Suspension arms jack pad

Post by philthehill »

Les
The idea of fitting the plate on top was that the head of the jack was securely held between the 'U' Bolts. The 'U' bolts preventing the head of the jack from sliding on the underside of the suspension arm.
Of course these jacking plates when fitted correctly are only suitable for the jacks as supplied to the Post Office. Trolley jacks need an alternative to the plates/U bolts if the same outcome is required.
Phil

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Re: Suspension arms jack pad

Post by les »

Yes I appreciate that Phil, maybe on top would be considered more positive, however the jack I used was prevented from slipping by the U bolt nuts. Plate underneath had the advantage of protecting the underside of the arms from any damage from the jack.

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Re: Suspension arms jack pad

Post by silloyd »

philthehill wrote: Fri Oct 03, 2025 6:41 pm ... Trolley jacks need an alternative to the plates/U bolts if the same outcome is required.
Phil
Does anyone have a solution for a trolley jack or non-GPO jack please?
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philthehill
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Re: Suspension arms jack pad

Post by philthehill »

A solution to the problem of a trolley jack slipping is to fit a angle bracket to the jack pad which then hooks up into the gap between the bottom trunnion and the lower suspension arms.

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Re: Suspension arms jack pad

Post by les »

I made this item for use in conjunction with a trolley jack, it locates on each chassis leg and clears the sump. The jack being positioned centrally on the bar. The rear, I just rest a piece of thick ply on the jack pad and lift under the diff drain plug. Not sure but the saloon legs are probably similar spacing wise.
IMG_3897.jpeg
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Re: Suspension arms jack pad

Post by silloyd »

philthehill wrote: Sat Oct 04, 2025 2:22 pm A solution to the problem of a trolley jack slipping is to fit a angle bracket to the jack pad which then hooks up into the gap between the bottom trunnion and the lower suspension arms.
Thanks, will take a look at that :tu1:
les wrote: Sat Oct 04, 2025 3:27 pm I made this item for use in conjunction with a trolley jack, it locates on each chassis leg and clears the sump. The jack being positioned centrally on the bar. The rear, I just rest a piece of thick ply on the jack pad and lift under the diff drain plug. Not sure but the saloon legs are probably similar spacing wise.
IMG_3897.jpeg
Thanks. I assume that is a steel beam, can you confirm please?

I was wary about lifting by the diff drain plug, seemed a very small point to balance the rear and a lot of strain on the thread, but if it works it works! :)
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svenedin
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Re: Suspension arms jack pad

Post by svenedin »

I don't like lifting on the diff drain plug with a flat rubber pad on a trolley jack or even a piece of wood between jack pad and diff. Every time I have done this (which is a few) it has caused the diff to leak from the drain plug. I prefer to use a trolley jack that has a cup rather than a flat pad. This avoids putting all the weight on the diff drain plug. Alternatively jack on on the axle to the side of the diff and then place axle stands.


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les
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Re: Suspension arms jack pad

Post by les »

Yes, it’s a steel beam, well actually it’s a rectangular tube, the timber made from plywood layers. I take the point about the drain plug, the thought has crossed my mind, maybe I should hollow out the piece of timber I use, letting the area around the plug take the pressure.

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svenedin
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Re: Suspension arms jack pad

Post by svenedin »

les wrote: Sat Oct 04, 2025 5:50 pm Yes, it’s a steel beam, well actually it’s a rectangular tube, the timber made from plywood layers. I take the point about the drain plug, the thought has crossed my mind, maybe I should hollow out the piece of timber I use, letting the area around the plug take the pressure.
Yes you could just drill a hole in the wood so that the pressure is not put on the drain plug.


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les
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Re: Suspension arms jack pad

Post by les »

I’ll do that Stephen.

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Re: Suspension arms jack pad

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Bill_qaz
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Re: Suspension arms jack pad

Post by Bill_qaz »

Or just jack one side at a time under the spring and put axle stands under the axle tube.
Most trolley jacks with the pivoting pad the centre indent misses the plug and lifts on the case either side.
The ebay item seems a very expensive solution.
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Re: Suspension arms jack pad

Post by Mervin »

"Yes you could just drill a hole in the wood so that the pressure is not put on the drain plug."
That's exactly what I have done Steven. Not a hole through the wood, but a drilled recess to accomodate the protruding end of the plug. The wood then makes contact with the bottom of differential housing.
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