New rubber cones collapsing after 8 months?

[bob01b]

I put new front rubber cones springs on my 1963 8 months ago. I purchased Mini Spares FAM3968 standard cones along with genuine knuckles, upper arm bearings and bushings. After installation all was as expected with the suspension riding high and understood that over time it would settle. Now 8 months later, it sure has settled! It seems the front end is riding as low or lower than before I replaced the very tired original cones.

I have only driven the car under 20 miles since this work was completed.

All measurements are with the car on level ground

The first picture shows the drivers side cone. I cannot get a picture of the passenger side without removing the radiator. The distance from the bottom of the rubber where it meets the trumpet to the upper fused metal on the cone is 1.5 inches.

IMG_1514.JPG

The second picture shows the measurement from the top of the tire to the bottom of the wing opening. It is 1.5 on the drivers side, 1.25 on the passenger side.

IMG_1515.JPG

On both sides the axle rises from the differential to the wheel. I think it should be slightly down or level at the worst.

The spacing from the top arm flat to the bump stop on drivers side is .75 inch, on the passenger side it is .625 inch.

It seems to me these rubber cone springs are defective. If you agree, I will followup with Mini Spares on replacement. Thanks for your input.

[bob01b]

Correction, the tire to bottom of wing opening is 2.5 on drivers side, 2.25 on passenger side

[Spider]

I've had one go on me pretty much right away. Not fully cooked or something wrong with the compound, the other 3 on the car were fine, but that one was like a stale bowl of custard.

[1071 S]

I would be sending the pics to MSpares and asking them whats wrong. .. and expressing my dissatisfaction

I would not think that the rubber would settle for quite some time (e.g. years). The initial settling people talk about (IMHO) will be the struts being pushed fully into the rubber cone and the cone itself being fully engaged with the mounting in the subframe. The rubber is not cooking or going through any state change so there's no reason it should compress any further (other than the normal compression under load) until age related breakdown starts to set in - which took (many) years with the original material.

I measured the cones on 3 of my parts cars ranging in age from the mid 60s to mid 70s .. all sitting normally on their suspensions. They all have their original cones and all are within a gnat's whisker of 5 cm (2") metal to metal. Yours looks shorter to me...

Cheers, Ian

[Andrew1967]

I had similar issues with my 1275 S build some 14 years ago and ended up fitting Hi-Lo's front and rear to adjust as appropriate. NOS Rover bagged cones with all the correct Dunlop lettering moulded into them.

Initially I had to fit them to the front because the ride height was ridiculously too high but then the rears sagged and had to fit them to the rear to raise it up. More recently I had to raise the fronts.

The ride however is really nice, quite soft for a dry Mini.

Conversely my '60 sits at a perfect height on its 60 year old cones BUT the ride is a little hard.

[mab01uk]

This Minispares article linked below is worth a read.
Mini Dunlop Suspension, Cones and Hydrolastic Unit:-
http://www.minispares.com/article/Minis ... Suspension

I remember BL made the genuine rubber springs slightly softer during (or around) the late 1980's in an attempt to refine the Mini's ride quality. Downside was they seemed to sag in height especially on the front in a short time, whereas the original pre-1980's cones just got harder and settled but did not collapse.

[Spider]

When buying new Rubber Cones, especially in late years, I've tried to by them a minimum 6 months (and more usually around 12) before I need to fit them and store them in a cool dark cupboard. I've found that they need a bit more shelf time to finish doing what ever it is they do. I found this back around 2008-ish when buying a new set and fitting them, they settled and awful lot, much more than the original items did, it may have been with the originals they had already been sitting around for a period ? By doing this I've found the cones much more stable and settle less.

If the cones are routinely changed out around every 4 years or so, the ones that are removed, if stored out of sunlight, will come back to their original shape, and can be re-used, though they'll be a little firmer in rate. Swapping them out before they turn in to utter pan cakes, you can get 2 or 3 'goes' at the one set of cones. Likewise, if the Mini is only driven every once in a while, lifting it up on jacks in between times, will greatly extend the period between change outs.

The one that I mentioned above that failed, I'd fitted about a month before going on a road trip, I found that before leaving, that Hilo was already wound up more than the other side and while away, it was the morning's task to wind it up a turn or two before hitting the road, it was like having a slow leaking tyre ! Driving the car, it was clear that corner was quite soft too.

This Minispares article linked below is worth a read.
Mini Dunlop Suspension, Cones and Hydrolastic Unit:-
http://www.minispares.com/article/Minis ... Suspension

Interesting read and thanks for posting up.

I was sent a pair of Rubber Cones to test and trial from China a little while back, I never bother with the trial part ! On test, they had all the compliance of a block of hardwood ! They stood taller than originals too, I'd say one would break the compressor tool or pull out the threads in it trying to fit them - utter junk !

[bob01b]

Thanks for all of your inputs!
Bob

[Gary Schulz]

I am seeing something very similar to bob01b. I have had my car sitting on its new rubber cones for several months now and the front right side is sitting considerably higher than the left front. As a matter of fact I have the Hi-Lo's cranked all the way down and the right front is sitting too high and doesn't look right. I can get the left front to sit about as low as I want it when the Hi-Lo is cranked down on that side but the right side is 1/2" higher.

I have pretty much isolated this to one of the supposedly "high quality original pattern" springs having a different spring rate (durometer) or possibly physically different profile? Seems that all the springs behave a little differently and in this case I wish the front would settle way down.

I am almost tempted to throw in one of my set of compressed rock-hard originals because then the Hi-Lo's will have enough adjustment range and as I remember it, the car handles better too! The ride is very soft with these new cones and seems a little disappointing.

It is also an interesting puzzle trying to get the spring compressed and out of the subframe tower with that bolt sticking up from the Hi-Lo. Seems to interfere with the spring compressor threaded end...

[mk1]

These are supposed to be the best donuts by far.

http://www.m-parts.co.uk/index.php?rout ... uct_id=329

Personally I NEVER Had any issues with old rubber springs, it is only since I started replacing them that I have had any issues whatsoever. TBH, I wish I had never chucked any of the old ones.

[MiNiKiN]

A bit of lateral thinking or talking BS (whatever applies):
could this uneven settling between RH and LH on Mini rubber cones( 2x RH side on cars which have been mainly standing) be due to uneven weight distribution between left and right?
Big cast lump on the right and less weighty aluminium bell housing on the right.
Or just coinsidence that it happened twice to the right side?

Generally, metalastic components don't like standing - they suffer lotsa settling when they see constand rather than alternating loads.
This of course only happens with new rubbers, they settle most under load when new and then the settling decreases over time.
The settling is of course load-dependent.

[Gary Schulz]

If anything I might think the RH side had a bit more weight due to the flywheel but I am not sure that difference is significant. Anybody who has spent a lot of time messing with corner weight adjustment could comment on that. My RH side is way too high. That one spring is not really settling at all. Here is how high it is after several months with the Hi-Lo fully bottomed out-

20200708_075033.jpg

Here are the springs I used which I think are the same as the ones Mark posted?

20200708_080122.jpg

[CooperTune]

I have replaced a lot of rubber springs. At first I would cut 1/4 inch off the front trumpet and 5/16 off the rear and know
it was going to be high for a month or so then settle to about what I'd want. Then they started having different rates of settle.
Now jut use Hi-Los which allow me to not only pick my ride height I can corner weight the car. I like to have even across front
and allow the rear to split the diff. I just happen to have every spring I have removed over the last, who knows. Some I have written
on date removed. Some come back up a little some a lot and other never again. When I was racing I built a spring tester to rate
rubber springs. I sold the stress gauge on, have to look for the rest a frame , mount for upper arm and small bottle jack. Steve (CTR)

[Gary Schulz]

Thanks Steve. I am using older Hi-Lo's and at their lowest setting the front of the car is too high with the RH side being the highest. I may just disassemble the whole thing and drop in a set of ancient rock hard springs. I also greatly prefer the way the car handles with my ancient springs. The car is far more comfortable (almost mushy) using the new springs.

[timmy201]

The ones in your photo are the Moulton/Minisport ones?

The Moulton/Minisport ones are made using the Moulton test equipment by Avon

The M-parts/Minispares ones are made from the Rover/Dunlop factory tooling

I went with the M-Parts ones as they seem to have more positive reviews

[CooperTune]

I have a set of Mini Sport smooth a rides which are a strange shape. I also have a set out of a Choke appear to be made of stone.
Would suggest you order a set of the Mini Spares racing rubber springs. I have run a set on the front of my street car for years.
They are a little harsh but not as bad a old ones. Another issue I have run into with Hi Los on the front is the threaded rod hitting
the nut in the spring which stops the lowering process. I recently install springs and Hi Los in a Moke. Kind of evened them up and
stuck them in. First scale was 68 lbs different across the front. It was much easier with the old style Hi -Los four rulers 4 keys and
a set of scales. Steve (CTR)

[mab01uk]

Personally I NEVER Had any issues with old rubber springs, it is only since I started replacing them that I have had any issues whatsoever. TBH, I wish I had never chucked any of the old ones.

I agree, never used to be a problem years ago, so from now on I am not replacing or chucking any old rubber cones.....I think the problems first started when BL tried to soften the ride in the 1980's and maybe the 'recipe' or manufacturing method/qualities for the rubber of the original long lasting 'hard' cones was lost in the process.

[Gary Schulz]

I am getting ready to throw a set of "rock-hards" circa 1964 into the front side of the car and I was just reviewing what I need to do to remove the new mushy springs. It is a bit of a challenge with the Hi-Lo's because of the interference of the Hi-Lo bolt with the nut in the cone. Also, do I really need to remove the upper suspension arm completely to remove/replace the springs? The pivot pin looks like it will hit the brake fittings on the subframe long before the pin can be removed so I am a little confused on the necessary minimum steps required here. Also pivot pin removal on the radiator side seems like even more of a challenge. Are you supposed to do all the work though that little access hole in the side panel?

Is there an "easy" way to replace cones without so much disassembly?

EDIT: It looks like you don't have to remove the pivot pin but just shift it forward enough to allow the back end to swing away from the subframe so the upper arm can be removed. I guess I knew that already!

Specific question- What part of the center bolt do you machine on the Hi-Lo in this thread (viewtopic.php?f=3&t=25317&hilit=machining+HiLo)? I want to make the Hi-Lo adjustable lower because just as everyone else has observed, they are way too high when using stock cones. Why are they made wrongly???

[Spider]

Garry, by all means change out your new cones if you're not happy with them, but of you put those aside for about 12 months - or longer, they will stiffen up. As Rubber ages, it does get harder. Personally, I'm not sure I'd want to ride around on Rubber Cones that are 20+ years old regardless if they are squashed or not.

Yes, you do need to remove the top arm. Getting to the Radiator Side 1/4" Inboard Screw is a little tricky, though, I usually come in from the front with a 1/4" Drive Socket and a load of extensions. You may not be able to remove the 1/2" Nut from the back completely in one go, as it may foul on the Body, but if you move the Pin forward it will give you the last bit of bite you need to remove the Nut. Once a the 2 bolts are out of the front and the nut is off the back, as you side the Pin out, tilt the Arm so the Pin starts going uphill on an angle and it will clear the Brake Line. It is a fiddle, but doable.

Reassembly is much the same, I actually pull the front Seal up, over the Arm until I get the Pin in and the Nut started on the back, then flip the Seal down and work it with my fingers until it's seated, then get the Bolts back in.

In regards to the Hilo Bolt, you can machine it back in length, but I find you can get them to a 'sweet spot' where they will slip in OK, yes, you will have to wind the compressor up a bit more, but they will go. If you do cut them back, you'll want to be sure you have a minimum of 20 mm thread engagement on the Hilo Body when at the ride height you are seeking. This will give you a further 5 mm of safe height adjustment.

I can't speak for the guys who make these as to exactly why the Bolts in them are so long, but I will say, they are a Hilo. While possibly many use them to lower their cars, some - like me - use them to raise the ride height and trust me, it doesn't take much to run out of safe thread.

[tmsmini]

Long extensions definitely come in handy for that side.