Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Todays jobs - preparing for the springs

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. 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. Pictures will follow when the real job gets underway.

I feel so a-technical if I read this! Respect Dave!

Looking forward to another master class....

Dave. If you want to compare before and after static height of the rear springs you can measure the distance from the centre of the wheel nut to the floor and the vertical distance between the underside of the chassis rail and the floor and then deduct one from the other to get the height of the centre of the axle above the bottom of the chassis rail. Obviously this is then going to vary dependant on fuel load, and weight of the spare wheel etc. At least recording these figures would give a reasonable basis for before and after spring change comparisons and comparisons between similar models fitted with different springs.

Ideally this should be done with the dampers (shock absorbers) disconnected but a gentle bouncing up and down of the rear of the car should settle everything into position. The floor must be absolutely level for this so that all 4 wheels are on the same level. If one of the front wheels is on a different level it would throw additional load on the diagonally opposite back wheel.

On my car the rolling radius of the 195/60 R15 tyres averaged to 292 mm (the distance from the centre of the wheel nut to the floor) I did not worry about pressure but it was probably about 24 psi. It is not really important for the calculation. There was 2 mm difference between left and right.

The height of the lower chassis rail was average 174 mm (there was 2 mm difference due to the tyres, in other words the springs were amazingly equal so a comparison left to right was unnecessary).

By deducting the 174 from 292 we get 118 mm which is the height difference between the centre of the axle and the bottom of the chassis rail. The car was unloaded with half a tank of fuel.

I hope that makes sense.

I does Peter, but now I'm without spare, luggage rack and exhaust, so no more "before" measurements are possible!

Here are some pics. First the offside front spring hanger and seat belt mounting. Inconveniently masked by the main silencer (now gone) and the fuel lines. The seat belt nut is 16mm, the bolt, 17mm, as is the bolt on the seat backrest. It's just possible to lever the pipes away to get a ring spanner in. I've released the pipe clip aft of this position because the allen headed setscrew is accessible in the axle well, but the one ahead is behind the sill trim, which I don't want to disturb. Here you can also see that I lifted the exhaust bracket (a while ago) because the bobbins were stretched. The studs are captive so no problem with adjustment.


This is the elongated hole in the floorboards to allow access to the front propshaft UJ nipple. The alternative was to cut a hole in the tunnel, but in the end I took the easier route. Its position is just aft of the crossmember.


I marked the propshaft so that I can rotate it easily into position next time.


This is the nearside and the red arrow (which will appear I promise) shows where the spring bangs on the wooden bulkhead on full compression. The wood is slightly splintered and flattened here on both sides.
Clearance here is 3.2cm nearside, and 2.8cm offside.


This is the offside and shows where the wood had been overcut. This is my araldited patch, covered with Dinitrol 4941.


This is the inside. It needs a good clean when I get the seats out. The spring cover plate was extended on this side to cover the hole.


Nearside.


Contact point on the spring.


The spring covers have received the DaveW treatment. You can see the wider cover from the offside. Basically trimmed with extra leather and neoprene to cover the bare metal. I've grommeted the holes and patched two areas which had wear from the seat belt bracket.


On the back, the pop rivets prevent these plates from closing up properly against the wood, so I've filed off as much as I dare to improve the fit.


Final job today was to insulate the fuel lines. They sit close to the cat and exhaust , and it's a job I did on the Roadster some time ago. Its fiddly and took quite a while, but now it's done. The pipes pass very close to some studs, so its worth checking that there is no chafing.

Dave you have been very busy and the end result looks well worth the effort.

Neat work as ever.

Dave. Are these the Suplex asymmetrical rear springs that are designed to reduce axle tramp?

Dave what did you insulate the fuel lines with?

No Peter, they're the 4 seater conventional 4 leaf springs from Mulfab. I don't get much tramp on the Plus4/4 - maybe I'm not trying hard enough!
John - its a sheet of woven insulation from Agriemach, cut to size to fit between the brackets and wrapped. Then sealed with Reflect-a-cool (Agriemach again) and held with cable ties. The cable ties are protected with Reflect-a-cool because I suspect that the heat will harden them, and the whole thing once done looks quite neat. But its hellish fiddly and took all afternoon.

It gets really hot under there. I have two aluminium skid plates under the exhaust brackets. The front one was just touching the exhaust pipe, and on the Scottish tour, the point of contact melted the aluminium.