Diff Mag Plug

[ScottR400D]

On advice from the manufacturer, when fitting my SPC LSD I also fitted a magnetic plug in the fill hole. 

This is it after 1000 miles, all OK according to manufacturer. A lot better there than floating around in the oil. 

[O.G.]

I would check it again in another 1000 on the expectation that it would be clean.
This would be similar to aircraft philosophy after fitting a new unit.

O.G.

 

[Geoff Brown]

After my problem with the mag plug striking the de Dion & IMO not possible to modify without effecting the integrity of the plug I decided to have another go at the problem.

With the help of the existing witness mark on the plug face & a marker pen line as a guide I judicially removed material from the flat involved at about thirty degrees until I had half of the thickness of the flat remaining. 

With the weight on the de Dion & later with the mass of SWMBO bouncing around in the drivers seat I determined that a little bit more would have to come off across one of the adjacent peaks.

The flats that are effected are at the top of the plug when fitted so can be avoided when removing or refitting

With plug in, road test carried out - success - no witness marks on the de Dion & I am relieved to have done the job especially after seeing the picture from ScottR400D.

Have only completed 350 miles on the SPC LSD so will probably pull the plug for inspection at 1000 miles. Photographs will be published !

  

Salutary tale of how useful mag plugs can be. In another life just completed a pond crossing to Gander, Newfoundland & the out of phase check of the power plant mag plugs became due. Number 3 reduction gear box mag plug was interesting. On removing the self locking plug there was a two inch 'fir tree' of multi coloured swarf on it ! I did not require EFDC back at base to tell me it was a QEC change.

Just wished that it had been Bermuda or the Bahamas instead of cold but hospitable Gander!

[Dave Hardcastle]

Just checked mine after 2400 miles, same as ScottR400D. Shall be checking again in around another 1000.

[7Up]

Can you check the plug without oil splling out?

I have one of these magnetic plugs. 

[Geoff Brown]

If the oil spills out the diff is over filled.

Caterham used to recommend filling until the oil runs out which is approximately 1.1 L.

To circumvent the drive shaft out put seals from leaking (easy fix!) CC now recommend approximately 0.8L fill.