Dave Wellings on Replacing Leaf Springs
The reason for the recent sagging (apparently) is that when MMC changed from six leaves to four, the spec wasn't good enough and a different supplier was sourced in '2012'. I say this because Mulfab were surprised that Bumble was sagging, and think that he may be one of the last with the weak springs. It was our Scotland tour that really brought this to my attention.
Anyway, a few stats:
Almost all the fasteners are 5/8"AF.
The seat belt nuts are 16mm, the bolts are 17mm.
Extra Photo - The 4 Rear Seat Nuts ( Front ones ar recessed in the Cross Member )
New spring measurement of unloaded camber - 15cm
Old spring measurement of unloaded camber - 12.2cm
From lower plate to chassis - (bigger measurement = lower ride height).
Old springs - N/S 6.5cm, O/S 7.3cm.
New springs - N/S 2.6cm, O/S 3.0cm.
Gain in height ...3.9cm, ... 4.3cm.
Clearance to body where contact took place - old spring 2.8cm, new spring 4.8cm.
To underside of running board at rear (just in front of rear wheel):
Old springs: N/S 21.0cm, O/S 20.4cm
New springs: N/S 23.8cm, O/S 23.8cm
Gain .............2.8cm, ... 3.4cm
Next will be a road test. Pressures set to 24psi.
If I were a Boy Scout I would now be sewing on my Leaf Spring badge, next to my Kingpin badge, and Creative Use of Neoprene badge.
I've just got in a after a full day on the springs. The old one came off easy enough and when compared to the new has significantly less camber unloaded - it really has flattened out. It's been of great benefit to get the car ready before starting on the hard work though.
I've covered the new springs with Denso tape, and I'm really pleased with how this has gone on, although you have to be careful when fitting the spring, because it's quite easy to pull the tape out of line.
Before doing that I slackened the centre nut and first dribbled ep90 between the leaves, then later chain grease, before wrapping. Today I only had time to do the offside because it was a fight all the way.
The rear shackle is very hard to access, and with a well cambered spring, it must be compressed about 2" to locate the bolt. What makes it worse is that there is a washer each side of the shackle which is very tricky to relocate. So that took a lot of time, but the other side should be easier tomorrow.
The axle U bolts were not too bad, easier than the MGB, but access is terrible. For the front shackle pin, I used a couple of G clamps on the front of the spring and that worked quite well. This is hard work and I'm ready for a snooze. Pictures will follow when I get time.
So today I lifted Bumble onto the wooden blocks. First a few measurements for later comparison. Then off came the luggage rack and spare wheel. I took this opportunity to tie up the loose cables and tighten up the charcoal canister, so now there is nothing to rattle in the spare wheel well.
Then I made a hole in the slot between the floorboards to allow access to the front propshaft UJ. There is no in built access to this grease nipple. Next I removed the exhaust, because access to the offside seatbelt mounting is covered by the exhaust and the fuel pipes. Access is much easier with the exhaust out of the way.
Then I removed the seatbelt mountings from the chassis and the seats, and removed the front covers from the leaf springs.
Extra Photo - Front Leaf Spring Cover & Crews
Extra Photo - Seat Belt Mouting
On the offside the bulkhead has been cut too wide, so I've araldited a matching piece of plywood to reduce the hole size.
Clearance between the spring and the body where it has been knocking is 2.8cm - not much, although this is near the front shackle. The springs are marked and the wood is flattened due to regular contact.
You need to remove the seats and the spare wheel. Access to the rear shackles is through the spare wheel hole, and I really can't see how you could do this job with a Sport model without a spare wheel hole. Grovelling down behind the seats may be possible, but it would be unpleasant.
First a few observations:
Even the guides on line are rather sketchy on the best way to do this job, so it's very much suck it and see.
The rear shackle has to be lifted from the chassis with spring attached, because the spring bolt wont come out until the shackle is released. Access under the rear compartment is tight although the bolt head is on the outside of the chassis.
There are two thick washers - one each side of the shackle between it and the chassis. They drop into the chassis on removal and are very, very difficult to replace. On the nearside, both washers were on the inside.......
The U bolts - the inner pair are easy to get off and unwind easily. Mulfab told me that I could re-use the 7/8" U bolts.
The outer pair are much harder to access, an open ender is essential, and most of the fasteners on this job are 5/8"AF.
Anyway, on with the story......................
First a shot of Bumble's naked interior. I had selected a set of stainless screws to replace the mixed bag of fasteners which MMC provide to hold down the spring covers.
The body number is 4133.
Here's the Denso Tape - worth a punt I thought and used by Land Rover owners.
Here's the inside of the head restraint hole. It's a funny angle but you can just see a neoprene strip which acts as a holder.
This is my oddment box of seatbelt fasteners. I wanted to smarten up the lower fastener which goes into the chassis and found a couple of chrome bling bolts.
These are the new springs. Note that the camber is slightly different, so the higher one will go onto the offside - extra weight of exhaust plus me.
Part number - 4 Seater.
I left them overnight to soak up the oil.......
One had some damage to the centre through bolt, so I swopped it for one off the old springs.
First side was the offside.
This is the rear shackle bolt head.
Here's the other end with nut removed.
Once the shackle was released, I removed the U bolts, using small blocks of wood to hold the spring above the chassis rail for access.
Next was the front shackle. I used two G clamps as follows:
The bolt came out easily, but to be honest, the springs were so flat that there wasn't much tension.
Note the two captive bolts for the exhaust bracket to the left of the first spring keeper.
Here is the position with clamps removed. Not even pressing upwards on the body.
Here it is against the new wrapped spring - note the camber difference!
More to follow.................
I lifted the new spring into place from underneath. First slot forward, then back, with shackle attached.
The rear shackle was about 2" above the chassis mounting point and there's no room to lever, and no room to fit those two washers.
What followed was a period of intense frustration, as first I came to grips with how to push the new spring down far enough to locate the through bolt, The centre of the spring was touching the chassis and the front was hard up against the body.
A solution proved very difficult. In the end I went for cable ties (of all things!). Using cable ties I could hold the shackle down, but then fitting the two washers was frustration after frustration. Eventually I managed it............
This is why it was so hard:
The U bolts on this side almost fell into place - all you have to do is to keep enough clearance to get the nuts started, and manipulate the axle height using a jack.
So next came the front fastener - much more of a challenge!
Compare this with the old spring in this position.
So I had to be much more careful with the G clamps.
In no time at all..........
Job done.........(one side anyway).
More to follow...........
Day 2 and side 2 - nearside. This time I was more optimistic, having learned a few tricks on day 1.
This is how I did the wrapping with Denso tape.....
This is the difference between the nearside old and new springs.
I've added some neoprene sheet to act as a buffer in case the spring gets near the body. This is offside.
The rear nearside shackle was easier to sort, but those washers were a pain to get right.
The U bolts on this side took longer as I couldn't line up the spigot on the spring with the axle. Here it is, partly located with wooden blocks assisting.
Once the U bolts were properly tightened down - on to the G clamps.
The front fastener was much harder to locate than the offside which went straight in.
This one needed some persuasion. Note the neoprene gasket over which fits the spring cover.
And that was it. Two days of hard graft, but worth it!
On this side I fed the spring in from above and it was a bit easier to handle.
I'll post some before and after dimensions once Bumble is back on the floor. And now for another snooze.
We've been out for a test run today, and the rear is transformed.
No more crashing over potholes, and a nice firm well damped ride. Even MrsW noticed the improvement.
And that's another re-booted How To!
This is my sorry attempt at a lever. It was tacked together on the fly from bits out of my scrap box when I was wrestling with the front bolts.
It has LH and RH ends. It enabled a 10 stone wimp to do the job single handed.
I replaced my rear springs at the weekend two tools that made it easier/single handed were:
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