14 replies to this topic

[jameslearwood]

1993 rover rio 1275cc dry suspension 12" wheels

 

Okay so i want to drop the rear subframe overhaul it and put it back on relatively swiftly so I have a order ready to go for other parts so want to get anything i can in advance so any help will be appreciated.

 

what should be definitely replaced?

 

any parts to upgrade from standard?

 

The rear subframe is still attached but all fixing bolts are loose on axles ready to lower.

 

going to replace the drums and shoes + springs

 

running in new brake pipes whats the connector block on the rear subframe that kinda seperates the brake line out, called just looks like a t joint

 

already got the new dampeners.

 

the rubber cone suspension looks a bit dodgy so might be worth overhauling that.

 

What are the mounts i need already put solid in the front. rear mounts look well knackered.

 

anyone know what thread is the nut that reatins the gas adjust dampeners as the threads need a clean and the nuts replaced.

 

Cheers for any help

[nicklouse]

So what are the radius arm bushes like?


All thread size cam be found on MiniSpares website.

T piece.

Got new Knuckles? Good to replace as the arms are out.

Poly bushes are good for the rest.


Got your tank out yet?

[jameslearwood]

yeah the arms will need overhaulled 

 

never knew thread were there shall check.

 

knuckles?

 

T piece is where the main brake line comes in and then splits to each wheel on the rear subframe.

 

Tank is out looks good as new

[nicklouse]

Knuckles the joint between arm and alloy trumpet.

Getting reconditioned arms? As the bush will need reaming if you do it yourself.

[wile e coyote]

Not much to a rear frame - did the car crab or wheel to body alignment seem visually odd???  - if not standard end brackets good enough (you can fit adjustables if you want but if all's good why bother) probably a quick overhaul of the radius arms and plenty of greasing will probably see you ok. (may be worth  replacing the radius arm crud seals... they're really cheap but often missing)

 

Concur on new knuckles  - and polybushes for longevity but nothing wrong with std rubber on the rear, important thing is the condition of the frame and heel board - sounds like the front four mounting bolts have come out clean so signs positive... get a load of stonechip on the heel board before refitting and ......

 

 

one daft tip for you - when putting the heelboard bolts back in put  a load of  non setting gasket goo in the bracket holes before bolting up then  raid Mcdonalds for some straws fill 2" with copper grease and when the frame is back in - go through the bottom of the back seat bin and slide the straw end over the bolts..... - will hopefully come out clean again years down the line .....sounds idiotic but works very well - did a frame in late 80's and it came out sweet as a nut 20 years later.....

[Spider]

You can check the bushes & bearings in the arms - to a degree - while they are fitted, or you could get some reconditioned ones in any case since your time frame is short. See if these can be supplied with a pin kit, less the bush and bearing (as they'll already be fitted to the arms), as this has not only the pin, but also the thrusts and seals.

 

The thread on the Trailing Arm for the Shock Mount is 3/8" UNF, but if you're getting reconditioned arms, this will come with those in any case. The Thread on the top of the shocks are typically also 3/8" UNF or these days, M10 is also common. 

 

I would not recommend poly bushes, they deform in shape (from static pressure on them) and don't come back. They also crumble with little warning and have little 'give' like rubber does. There is a bit of a write up on the Mini Spares website about them. There are better quality rubber bushes about, you just need to look.

 

Sometimes the front mounting pins for the mounts can be rusted. While I've not had to replace them (as we don't get the rust problems you guys do), these may also be worth considering. I usually clean mine and send them out for plating, but I don't think time is on your side for that.

 

I've found that the brass Tee Piece for the Brakes 9999 times out of 10000 to be in good order, just tarnished. I don't ever recall having to replace one, though I do polish them up on the wire wheel so it not only looks good, but so I can check it for cracks.

[jameslearwood]

Okay cool that gives me an idea of what to be looking for.

 

was wondering about what to grease the bolt holes up with so will give the straw technique a try.

 

time isn't an issue more don't want to have to stop and wait for a new part.

wiil get some pics up as i start to get in and remove stuff.

[MikeRotherham]

Hi Wile e coyote

 

"go through the bottom of the back seat bin and slide the straw end over the bolts"

 

Can you explain this in more detail, how do you go through the bottom of the back seat bin?

[GraemeC]

For a full overhaul look to replace all perishable or wearing parts. So:

 

Bushes (stick with good rubber ones)

Radius Arms (recon ones by far the easiest)

Knuckle joints

Suspension Cones

Dampers

Brake drums, shoes, spring, adjusters, slave cylinders, handbrake lever gaiters.

Flexi brake pipes (could be upgraded but IMHO not worth it for a road car), solid brake pipes if badly corroded or don't come off nicely

Wheel bearings

Exhaust mounts

Handbrake cables

Brake back plates if badly corroded

 

Possible upgrade to hilos and adjustable camber/caster brackets

[DomCr250]

If you are going to remove the radius arms then assume that at least one bolt will shear off on the outside camber plates (4 on each plate), so make sure you have a drill and tap of a suitable size to fix it.

[Deeppockets]

I am in the middle of rebuilding my rear end. Are there any views on using waterproof/water resistive grease for the suspension bearings? 

 

It seems to me that most of the wear problems of the radius arm bearing are associated with corrosion of the steal pin which subsequently also wear the bush. Both pins on my '97 are significantly corroded at both ends, though worse on the outside. If the effects of the water and salt exposure can be minimised then surely that would be a good thing with corrosion minimised and service life increased. 

 

Waterproof grease is used for boat trailer bearings so could do the job, I have been looking at water pump greases and Morris K99 http://www.morrislub...ant-grease.html  - thoughts or experience welcome.

[tiger99]

I think you are on the right track but water pump grease possibly does not have the load carrying capacity. Not that it matters much if you use the original servicing schedule, which if I recall correctly was greasing every 2000 miles. But nowadays people want to do it every 6000 like the oil change, or in some cases never....

 

Generic boat trailer wheel bearing grease might be the best here. My only doubt is because boat trailers don't usually do much mileage, but against that the radius arm does not make as many rotations!

 

Ultimately the entire radius arm pivot area could be redesigned without too much difficulty to use better seals and replaceable inner sleeves for the bearings. Hopefully it will come. But for now, surely the Morris stuff is worth a try? It is almost a no-brainer unless someone finds an even better product.

 

The much bigger question is whether to also use it in the ball joints and front upper arms, or to keep a separate grease gun filled with LM for those. I don't see that cleaning out the gun half way through a service to change greases would be favoured by many.

 

I have just thought of a trick that may prolong radius arm life. I don't claim originality, as I suspect that I heard it before in some other context a very long time ago. Make a mark at one end of the pin, and at every service loosen the inner and outer nuts and turn it by about 60 degrees clockwise, and torque up again, before greasing. (You may need to machine spanner flats immediately behind the grease nipple, without going into the part of the thread where the nut finally ends up, to be able to turn and locate it.) That way you will be putting the load on a fresh face every time. I can see why others may disagree with that, so fair enough, please argue the point if you feel it is not going to work.

[Deeppockets]

Interestingly Castrol recommend their High Temperature Grease for Mini greasing, here are the specs sheets for comparison.

 

Morris K99 spec sheet: http://www.morrislub...-1458559790.pdf

Castrol High Temp Grease spec sheet:  http://msdspds.castr...XE-8F7A38_0.pdf

 

From my very limited knowledge the main difference is K99's reduced operating temperature range, though -20C - 100C should be OK for a Mini's suspension in England (-10C - 35C would be OK).

 

I have a couple of grease guns which I have inherited, so serious thinking of going down the K99 route for all rebuilt radius arms and ball joints as I go with a dedicated gun.

[Deeppockets]

Having fitted new radius arm bearings I have successfully managed to ream of the bronze outer bushes with a DIY reamer made from the removed parts.

 

Using the old pins removed from the arms I first joined them to get the length needed using a couple of the removed nuts (a weld spot on each side would have helped) and the corners of the nuts rounded off slightly to ensure clearance of the roller bearing. A removed bearing is useful here as a guide. With gentle persuasion I aligned the two connected pins by eye.

 

Taking a grinder I tapered an end to fit  the new bronze bearing as a starting guide (~1cm fit with ~ 3cm further taper), then cut linear groves along the taper up onto to the untapered pin area (~1cm) using a 1mm cutting wheel. I found that is was best if the whole tapered area was cut with grooves, about 25-30 in total.

 

Inserting the Heath Robinson reamer through the roller bearing to the bronze bush I was able to rotate the reamer with a spanner on the locked nuts while leaning on the end. After 10 mins the pin reamer was through and job done. Surprisingly the new pin was a good fit, finger tight with no play.

[tiger99]

Well done! I did something very similar in about 1970 and the new bushes lasted for a very long time, as should yours. In cases like this, skill, ingenuity and patience can replace fancy and expensive equipment that is not immediately available.

Oh, and I have had access to an original manual. Greasing was every 1000 miles. If that was done properly by previous owners, I don't think that there would be nearly as many replacements needed!