14 replies to this topic

[m1n1]

In 2005 my radius arms suddenly both developed play, so i went to minispeed near brooklands and swapped them for exchange units.   Some time later i realised they had roller bearings both sides, didnt bother me at the time thought it was a good upgrade! Some 6 years of use and probably the wrong grease used (moly - i liked it) the needle rollers had worn totally flat! I pressed new bearings into them but was never that happy and the o/s arm seems bent.

 

 So i replaced the bent one today with a brand new minispares one.   I looked inside and i'm positive the grease tube was inserted as the top of the bearing rollers were flush with the bore, although it wasn't white plastic like what you get in the kit.   You would never get a tube in anyway with the bearings fitted.

 

How many grease pumps from a grease gun does it take to fill it so grease pushes out the little rubber seals? i'm up to 50 pumps already... 

[mab01uk]

The plastic shaft grease tube sleeves often split and leak out the grease which then gets pumped into the hollow radius arm. Originally Mini radius arms had a steel grease sleeve which was much better for retaining the grease....

 

 

[Spider]

Gordon at Catmint does the original style grease tubes, the plastic ones are a 100% waste of time in my view.

 

https://shop.catmint...e-steel-21a396/

 

I'm not surprised you found your needle rollers worn flat, with rolling elements, like a needle roller, molly isn't a wise choice of grease as it does just what you found, it doesn't allow the elements to roll, but causes them to slide.

A decent quality chassis grease is a better choice, I'm not sure if this is available in the UK, but I swear by it;-

 

 

While molly isn't the grease of choice for the arms, it's actually a very good grease to use in your ball joints.

As a rule of thumb - if it rolls, a chassis grease, if it slides, a molly grease.

[gaspen]

Minispares sells the metal tube also

 

REAR RADIUS ARM METAL GREASE TUBE - Mini Spares

[m1n1]

Perhaps i will wait till winter, then when its tucked away i will do the other arm as well as strip off the one just fitted, wack out the bearing and fit some metal tubes!  they look fab

[sonscar]

Not an engineer but I always thought the movement was too small to allow rollers to work properly,same with the front top arms.There must have been a reason.Steve..

[bpirie1000]

Think the reason for roller bearings was purely down to the space available within the rear subframe...

Kind of NEEDS MUST.... must be narrow and must be able to go up and down...

[DeadSquare]

Think the reason for roller bearings was purely down to the space available within the rear subframe...

Kind of NEEDS MUST.... must be narrow and must be able to go up and down...

Early minis had a bronze bush at both ends.

 

I once had a rear subframe that'd been rescued from the "Failed experimental bin", which had quite a large recess in the front cross member, that apparently had been hand hammered to accommodate a modified Raduis Arm with a ballrace in it.

[Shooter63]

I have mentioned this before, but there is a very nice mod you do to the radius arm pin which does away with the need of the grease tube.
Countersink the original grease hole in the middle of the shaft, fit a brass pin into the hole and pean it to shut it off.
Put the shaft in a lathe, bore a hole the correct diameter to take a grease nipple and tap, make sure the hole is deep enough to reach the bearing, now cross drill the shaft to intersect your drilled and tapped hole central to the bearing, fit a grease nipple to the inner end, fit the pin as normal and pump grease in from each end. As you've shut off the original hole the grease has no option but to go into the bearings.

Shooter

[Spider]

Another option to Shooter's is to drill the arm, on the top side,just inboard of the bearing and bush, tap and fit angled grease nipples here.

The Grease Tubes I make up I fit I rings to, once they are 'primed' one or two pumps is all they need. While the steel tubes are waaay better than the plastic ones, they still leak in to the arm. These with the O rings don't leak grease and likewise, don't let water in.

[Shooter63]

Another option to Shooter's is to drill the arm, on the top side,just inboard of the bearing and bush, tap and fit angled grease nipples here.

The Grease Tubes I make up I fit I rings to, once they are 'primed' one or two pumps is all they need. While the steel tubes are waaay better than the plastic ones, they still leak in to the arm. These with the O rings don't leak grease and likewise, don't let water in.

I think I know what you mean, can you post a piccy so I can blatantly copy it

Cheers

Shooter

[Spider]

I think I know what you mean, can you post a piccy so I can blatantly copy it

Cheers

Shooter

 

The grease tubes ?

 

Not the best photo of them. These are for a Moke (which has needle rollers both ends), I have done them for Minis but more tricky.

 

[imack]

I have mentioned this before, but there is a very nice mod you do to the radius arm pin which does away with the need of the grease tube.
Countersink the original grease hole in the middle of the shaft, fit a brass pin into the hole and pean it to shut it off.
Put the shaft in a lathe, bore a hole the correct diameter to take a grease nipple and tap, make sure the hole is deep enough to reach the bearing, now cross drill the shaft to intersect your drilled and tapped hole central to the bearing, fit a grease nipple to the inner end, fit the pin as normal and pump grease in from each end. As you've shut off the original hole the grease has no option but to go into the bearings.

Shooter

I carried out this modification some years ago, think I saw it on the mk1 forum.
Well worth the effort. Fresh grease is injected directly into both bearings, rather than hoping some reaches a bearing.

[Shooter63]

I have mentioned this before, but there is a very nice mod you do to the radius arm pin which does away with the need of the grease tube.
Countersink the original grease hole in the middle of the shaft, fit a brass pin into the hole and pean it to shut it off.
Put the shaft in a lathe, bore a hole the correct diameter to take a grease nipple and tap, make sure the hole is deep enough to reach the bearing, now cross drill the shaft to intersect your drilled and tapped hole central to the bearing, fit a grease nipple to the inner end, fit the pin as normal and pump grease in from each end. As you've shut off the original hole the grease has no option but to go into the bearings.

Shooter

I carried out this modification some years ago, think I saw it on the mk1 forum.
Well worth the effort. Fresh grease is injected directly into both bearings, rather than hoping some reaches a bearing.

I think that's where I first saw it, alot of what the guy came up with was wierd, but that made good sense.

Shooter

[Spider]

Something smiliar to that came out in a factory Technical Bulletin in about 1960 or 61 when the Arms still had bushes both ends.