inca|yellow

Changing the propshaft

After the nightmare of the weekend, it was a relief that the fix would likely be a simple replacement of the propshaft.

I sourced the new prop from MGOC; I'd hoped for a new one, but there was no stock available so I went for a refurbished one instead. This does mean I'll have to return my old one in exchange, but did work out cheaper.

The prop is held on by just 8 bolts. At the gearbox the bolts are semi-captive - they're loose in their fittings but you'd have to actually remove the flange to take them out; the bolts here also have special heads to lock them against the flange when tightened - at the diff end they're just standard bolts and nuts.

Removing the nuts is simple but fiddly. I had the back of the car on axle stands, so to hold the shaft in place I had to apply the handbrake. This meant that each time I moved to the next bolt I had to release the brake, rotate the shaft to show the next nut and reapply the brake. As I said, fiddly but not difficult.

Once all the bolts were released, the propshaft can just be pulled forward slightly and then dropped backwards through the tunnel towards the diff. Putting the new one back in is just as simple and fiddly!

A quick test of the new prop showed no problems - the real test would be the next weekend with a 400 mile round-trip to Blenheim Palace.

categories: see more posts related to transmission

Comments

  1. Tom Brearley said on 18 Nov 2012:

    I wonder if the overdrive falling out (at speed) into 4th gear showed up a vibration resonance in the prop shaft at high revs that caused it to fail? Hard to think how loss of gear oil and bad prop shaft would be connected otherwise... Glad you got it all sorted in time anyway! Liking the blog very much.
  2. gavin ablett said on 20 Nov 2012:

    i have just done this to try to reduce the driveline clonks. the spines on mine and quite a lot of rotational movement. like you i hand the baxk axle up on stands. As i am getting the wheels powdercoated and new tyres fitted. i found i could simply pull on the handbrake link cable on the back axle inorder to lock up the prop whilst i loosend the nuts.
  3. Adam said on 20 Nov 2012:

    @Tom - would be a weird coincidence otherwise eh? @Gavin - good thinking about the handbrake - should have thought of that!