15 replies to this topic

[Peterg1]

Right I have sent my rear subframe off for powder coating, remove both rear radius arms.
Thought I would give them both a clean and refurb. So I took out the pivot pins, bearings and phosphor bronze bush.
Was just about to order the new pivot pin kits withe new bearing and bush, but they all say the bush will need reaming when fitted!!!!! Another pain..
Does this always need to be done, wondered if there was another type of kit out there that does not require reaming... Need to know before I order the two repair kits!!


Cheers

[richmondclassicsnorthwales]

Hi, Yes, It will need reaming. You will not get the pivot pin through with out doing this.

Regards, Neil...............

[danie garry]

seems to b a tried and tested method of keeping the radius arm on the car so i think its the best way! i did bring up the idea of using two of the roller bearing berofe and i think that i got an answer saying that at 1 stage thats how it used to be. but i think best to use the bush and get it reamed out

[medicalgradenitrous]

any local machining shop will have a the correct size reamer 13/16 will take them about 10 mins to do , do it nice not twice !!

[Vipernoir]

Make sure whoever reams them for you has the correct gear for making sure it is perfectly in line - the bush needs to be reamed true to the bearing or it will wear very quickly.
 

13/16" is the nominal size of the pin, the reamer needs to be a thou or two larger as per the original tooling.

[mini-geek]

Often the bush dosn't ware out, the pin trends to be the issue, so often you can just replace the pin and it will be as good as new..

[dklawson]

While it is true that the pin often takes the greater amount of wear, replacing the pin alone is not applicable in this instance since PeterG1 says he has already removed the bush from each arm.

 

Peter, there are lots of threads on the topic discussing how to(s) for DIY and the need for the correct tool.  Google for them and you will find lots of information on the process.  As Viper said, it's not just about reaming the bush to size, it's about getting it to size and inline with the needle bearing.

[mini-geek]

While it is true that the pin often takes the greater amount of wear, replacing the pin alone is not applicable in this instance since PeterG1 says he has already removed the bush from each arm.
.

Still relevant to anyone else who's got a worn rear radius arm tho..

[Craig89]

I have a 13/16 reamer and the way I did it was to cut the end off an old pin and put this in the tailstock of my lathe, then with the reamer in the jaws I put the radius arm between the two. Having the radius arm supported at the rear with the correct diameter pin ensured alignment for the reamer

[tiger99]

That is a good way of doing it, given a lathe....

 

As so the suggestion of using two needle rollers, sad to say it can't be done. The OD of the needle roller is larger than the bush, and there is insufficient metal in the arm casting to be able to bore out the end to the correct diameter. I spent ages looking at this to try to find a way, but it just is not possible. You could possibly find a metric sized needle roller, and regrind and harden that end of the pivot pin to the correct diameter (the pin is structurally safe with some diameter reduction at the end, bearing in mind that the threaded portion is large enough to carry the shear load safely). But, then the needle roller bearing would be carrying a rather heavy load, and would most probably fail.

 

The early arms used two bronze bushes, not two needle rollers, but the amount of friction was deemed to be too high for the suspension to operate as intended. Early Australian mokes were known to have used two taper roller bearings, an arrangement which interested me considerably (because I don't like to have to ream bushes either), but it turned out that the arms were longer, and will not fit a standard Mini.

 

There are other things that could be done, perhaps for discussion another time....

[Peterg1]

What a right pain!!

I should have left the bush in place....

[Vipernoir]

A friend of mine used to convert standard arms to having a roller at each end as he believed it to be better.
Chewed up bearings in next to no time but he didn't care.

 

Somewhere in one of my piles of treasure I have a standard arm with two rollers fitted.

[Peterg1]

Well have purchased two refurb kits and taken the lot to an engineers to refit and ream out the bush..

Quoted £20 to fit them..

[tiger99]

That is a good price!

[Carlos W]

I paid 70 quid exchange for a pair of refurbed arms with new pins!