An Article from MASCOT  Mar - April 2005

Trouble Finding the M11? - from Mike Hyman

None at all really, it’s Junction 27 off the M25 and … Not THAT M11, silly, the M11 Oil Filter cartridge for the SM 1500 engine.  Oh THAT M11, well they are getting very scarce aren’t they?  Indeed they are, but what can you do about it?  The answer came when I was fitting what must be one of the few remaining new filters in the country to Monty, my 1953 SM 1500 saloon.  Whilst I still had one in my hand I took it to Camberley Auto Factors to see if they could come up with a replacement. The one they have listed as an equivalent is far too small, but I did manage to find a MANN H720x filter that looked very close, so I decided to see if I could engineer an adaptor.   I needed

to replicate the seal arrangement at the top and the spring location at the bottom, but what better to use than the end caps from the old filter?

The procedure is as follows:

1. Cut the old paper filter off the bobbin - a dirty job for which I recommend using rubber gloves.

2. Cut the ends off the bobbin, leaving about an inch of the centre tube on each end piece as a register, and clean off the residual paper and adhesive from the inner faces.
3. Cut two washers about 2.25” od x 1.25” id from 4mm thick cork sheet and glue these to each end of the new filter. Evostick or similar used sparingly should do the job - it will all be held together by the spring when assembled to the engine.
4. Glue the end caps to the cork seals and your ‘new’ filter is ready to install.

NOTE A. Unless there is physical damage, the old gasket and fibre washer should still be serviceable - I would suggest a smear of sealing compound to be on the safe side, but do check for leaks before you drive off.

NOTE B. There are two types of M11 cartridge - one as shown, which has a thick fibre washer, and another which has a raised sealing platform with a smaller diameter hole and uses a thin fibre washer. The washers need to be a good sliding fit on the centre tube of the canister.

NOTE C. The MANN H720x filter is used on Mercedes and some Daimler-Chrysler models. Equivalents are: Fiaam FA 4361; Fram CH-962Pl; Hengst D 07 E 117.26; Knecht/Mahle OX 47 D;
Tecnocar OP 830.                
         Anyone fancy a drive to Cambridge?                         Mike.