Morris Minor Owners Club

At some point soon, I will replace the rear damper link arms and drain and re-fill the dampers. The rubber bushes are shot and the link arm is grotty as well.

Having had a quick look just now, I can't see the remains of the split pin in the castle nut where the link is attached to the body. Assuming that the split pin is still in there, even though I can't see anything, what is the best way to undo the nut without causing any damage? I'm thinking that the remains of the split pin would shear off before anything else is damaged?

Second question - has anyone successfully used poly bushes instead of the supplied rubber bushes? I see from this thread that someone found the poly bushes too wide: viewtopic.php?t=57734&start=20

Third question - to remove the link arm and damper I'm gonna jack up the rear of the car and put axle stands under the axle. Is there anything else I have to do (like support the leaf spring with a jack while the car is up on axle stands?)

Any other tips to make this a simple, easy job? I will spray all nuts and bolts beforehand with releasing fluid.

I have done this job with help from the members of the forum. I used new drop links from ESM and they already had a rubber bush fitted in the top. It looked to me that a poly bush would not fit and since the rubber bush was new I never attempted to swap the bush. I didn't want to destroy a new part to find a poly bush would not fit. There was a lot of mess and grease that made it hard to find the old split pin but they were actually there and I did get them out. Although not exactly the same, I had terrible trouble with a front tie bar split pin and the nut really didn't want to undo without all of the split pin out. It amazed me how it hung on for dear life. With both the tie bars and the damper links I have used nylock nuts instead of castle nuts and split pins. I just can't face that fight again......

I had the body of the car supported on blocks of wood and axle stands and the axle independently supported. It seemed daunting but went pretty easily really.

Since both my lever arm dampers were leaking I just swapped them for refurbished units. I thought that it was likely to be a waste of time to try to refill them and have them leak in short order. This work was part of a total rear suspension overhaul which included new leaf springs. It made a very significant difference to the handling of the car and was well worth the effort and expense. Before I did the work the car was hitting the bump stops and was bone shaking over speed bumps even driving very slowly. Now it is much better though I still go over speed bumps much slower than modern cars do.

Stephen

Thanks, Stephen. I'll stick with the rubber bush supplied with the link arm then. The old rubbers have done well, I think. The split pins may be visible once I've got there with a wire brush and some penetrating fluid. If I can at least find the holes, I may be able to punch out the remnants of the pins with something suitable. At worst, if there is nothing to grip hold of, I can just remove the nut and punch out the remains of the pin from the stud in the body.
I can see why you would support the body of the car as well as the axle if you are replacing the springs, but I think axle stands under the axle itself will be sufficient for just removal and replacement of the arms and damper.
I think the final tightening of the nuts at either end of the link is when the car is back on the ground, but does that apply to the damper bolts as well? Yes, a nylock will make things a bit easier......

The link between the damper arm and the body pin is now supplied fitted with a fitted single bush at the body mount end.
The bush is similar to that fitted to the classic Mini Cooper damper and that can be used as a replacement bush. The size is of the Classic Mini Cooper bush is correct for the Minor rear link. The top bush fitted to the ESM rear damper link is not available from ESM as a separate item but the Cooper item Pt No: 21A503 is the same as the fitted ESM bush.
I have used the classic Mini cooper damper bush for the rear gas tele damper conversion fitted to my Minor.
You do not have to fit the original type qty two bushes.
I would not recommend fitting the poly bushes in this location as the poly bushes are too tight and the articulation is very restricted.
You do not have to support the body when replacing the rear damper links. Supporting the car on axle stands under the axle is the same as having the vehicle on the ground. Therefore you do not have to have the car on the ground to tighten the damper link nuts.
Make sure that you put plenty of red grease on the damper link top bushes before fitting whatever type of bush is fitted.
If you cannot remove the split pin it is acceptable to use a self locking nut instead of the castellated nut.

Thanks Phil, that is helpful and being able to tighten all the nuts while the car is on the axle stands will make things easier. The job should be pretty straightforward once the split pins are removed.........I hope! Must order the parts now and get on with this. I procrastinated over the winter but now its warmer I can face grovelling around on the garage floor again!

just changed mine but didn't need to lift car but as other replies just stands under axle is sufficient. See
viewtopic.php?t=78649

Good luck! I did a great deal of grovelling around on the garage floor in the cold this winter and I did not enjoy it. It makes complete sense that you waited until the weather warmed up.

Stephen

Thanks, I will report back when I get to do this. I'm not in a massive hurry and prefer going to the beach etc. while the weather is good Oh dear, procrastinating again!

OK, about to order parts! Can anyone confirm the size of nyloc nut required for the link to chassis? The manual says it is a 5/16" nut but I am sure someone on here (Stephen?) has suggested it is 3/8" BSF. I see ESM sells nyloc nuts in both 5/16" BSF and 3/8" BSF and I want to order the correct one.....thanks.

Nut for top drop link fixing to chassis is 3/8" BSF according to Moss and ESM spares diagrams.....I used nylocks but to be absolutely honest, I can't remember what size they were. I think I would remember if they had not fitted.

Stephen

The thread of the rear damper link as recently supplied by ESM Morris is 3/8" x 24TPI UNF.
The original threads were 3/8" BSF.

philthehill wrote: ↑Mon May 19, 2025 2:37 pm The thread of the rear damper link as recently supplied by ESM Morris is 3/8" x 24TPI UNF.
The original threads were 3/8" BSF.

Phill, unless I am on the wrong track, we are talking about the stud attached to chassis where the drop link attaches at the top.

Stephen

Steven
As you had rightly answered the nut size question relating to the body mount in your post above I did the next best thing and pointed out that the nut now being used on the link itself is 3/8" UNF which is different to that of the original at 3/8" BSF.
As regards the body pin - to be absolutely sure I have just removed the castellated nut from the pin, tried a tap through the nut and can concur that the nut is indeed 3/8" BSF.
The spanner size is 5/16" Whit.
Phil

philthehill wrote: ↑Mon May 19, 2025 6:06 pm Steven
As you had rightly answered the nut size question relating to the body mount in your post above I did the next best thing and pointed out that the nut now being used on the link itself is 3/8" UNF which is different to that of the original at 3/8" BSF.
As regards the body pin - to be absolutely sure I have just removed the castellated nut from the pin, tried a tap through the nut and can concur that the nut is indeed 3/8" BSF.
The spanner size is 5/16" Whit.
Phil

Sorry for the misunderstanding!

Stephen

Gentlemen, thank you. I shall order 3/8" BSF nylocs from ESM then. Maybe the manual's reference to the "5/16" nut" was mixed up with the spanner size?

I have just found a nearly full bottle of B&Q 4-stroke oil, SAE 30 in the back of the garage. Can anyone confirm this would be suitable for the rear dampers?

myoldjalopy wrote: ↑Wed May 21, 2025 11:09 am I have just found a nearly full bottle of B&Q 4-stroke oil, SAE 30 in the back of the garage. Can anyone confirm this would be suitable for the rear dampers?

Some people will no doubt say yes no problem. I think it will be OK but is not quite ideal. Jack, fork and dedicated lever-acting damper oils have anti-foaming agents added. How important that is I don't know. What is certain is that SAE 30 in the dampers is better than them being empty! From a quick search SAE 30 is a bit heavy for the dampers and may lead to a harsh suspension. You may find they leak when filled up in which case you will need to exchange them for rebuilt units. Your time will not be wasted because at least they will be easy to swap, having freed off all of the fixings.

I found this posting: https://www.mgexp.com/forum/mgb-and-gt- ... 798/page-2

Stephen

Thanks, Stephen. I have now ordered this, which should be better: https://www.dynolite.com/product/dynoli ... orber-oil/

myoldjalopy wrote: ↑Wed May 21, 2025 2:15 pm Thanks, Stephen. I have now ordered this, which should be better: https://www.dynolite.com/product/dynoli ... orber-oil/

That’s what I’ve used. No issues. I’ve also used the Penrite one and jack oil over the years. Can’t say I really noticed anything between them


Stephen

Whatever oil you choose, do not fill the damper to the very top--there must be an air gap (as per the workshop manual). The leaks after refilling are probably more often than not due to overfilling rather than the choice of oil.

Don