mardave cobra diff woes

[fidspeed]

hi folks

having picked up a modified cobra from legend of the north west roger woods collection . im having diff woes

im not sure if my diff is "special" thanks to roger or a std mardave diff
im struggling to find much info or exploded drawings or manuals

I have an early diff which has no diff plates and balls run directly on diff halves my modified one has diff plates (approx. b4 size) there does not appear to be any spring or belville washers and the diff adjustment screw is locked by a grubscrew ala Schumacher

can anyone help with drawings or info any where

regards dave

[Steve.T]

Best bet is to try Madave directly.
If they can't help, then a copy of the original instructions has an exploded diagram of the car, if I remember my old one correctly.

[adey]

Pm sent

[DerbyDan]

Hi Dave!

The diff with the locking grub screw sounds like its actually from a Meteor? I was playing about with different Mardave diffs I had when I built up the LWB Meteor from last year's Revival - I was looking at using some Cobra outputs/diff halves in the Meteor..... & they are basically the same & would have worked - except the slots for the driveshaft pins aren't quite as deep on the Cobra parts, so would have caused binding when the suspension was compressed. All my Cobra diffs (which were original 90s parts) had a plastic/nylon insert in one half for the diff screw to tighten into.

Both Meteor & Cobra diffs should have bevelled washers between the head of the diff screw & the 1st thrust washer (Meteor diffs seemed to just have an outer washer with the thrust balls running direct onto the ledge of the machined outdrive) The Cobra manual suggests that there are six bevelled washers but I must admit I don't think I've ever come across a diff with that many in?.... Mind you, they are so small that they tend to flatten out & even disintegrate in a poorly maintained car.

The fact that the Cobra diff didn't have replaceable washers wasn't a problem when a complete new diff was so cheap (BITD) - But in honesty, whilst the ultimately smooth free acting diff maybe difficult to achieve, once the balls have caused pitting/wear on the diff halves, a decent diff action should still be achievable if kept clean & freshly greased.