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Oil Change Tip
This was posted on BMW Bavaria Defense Mechanism reader mail page by Kevin McDonald. Some basic info here but worth a look for you new owner klowns that actually want to get your hands dirty and attempt your own little oil changes. Personally, I would change - the chance of it completed successfully are 1 in 2.5 Million. Can you imagine the local Jiffylube monkeys staring at their filter selection?
Here is a 'tech tip' for any E3/E9 owners or for that matter any BMW model of that era. It is a MUST DO if you want to minimize wear (top end wear in particular) - I have stunned service staff at 3 dealers with this (one a service manager "I've never had to replace one")- it might also be a comment on certain dealers staff. It is in regard to servicing/replacement of the cartridge oil filter on the older models, the one with centre bolt holding the can together.
Tip: The filter cartridge is held in place by a spring in the base of the can which pushes on a retaining plate that locates in the bottom of the filter unit - this plate has a neoprene bush in the centre with should fit snugly around the bolt, EVERY TIME YOU REPLACE THE FILTER CARTRIDGE INSPECT THIS BUSH FOR:
1. If it has gone hard from the heat of the oil.2. If it has any cracks in it
3. If it has shrunk away from the plate it sits in (loose fit in hole)
....REPLACE IT MUCHO PRONTO!!!. If you examine the design of the oil filter, pressurized oil from the pump enters the filter housing on the outside of the filter, and passes through the filter to the inside then up the centre to the oil galleries - the pressure differential between the inside and outside of the filter cartridge can be 30 p.s.i if the filter is blocked -
THERE IS A MUCH EASIER ROUTE FOR THE DIRTY OIL TO TRAVEL IF THIS BUSH/GROMMET IS NOT SEALING TIGHT (EVEN IF THE FILTER IS NEW) AND THAT IS STRAIGHT THROUGH THE BUSH!! by-passing the filter with crap straight from the sump - hands up all those who have used sump cleaning additives just before changing the oil
- think about what's going into the motor if the filter "ain't workin'". I have in the past bought a car in which there was NO!! bush (you may as well leave the filter out).NOTE: THERE IS A RIGHT AND WRONG WAY TO INSTALL IT TOO, the surface that seals on the bolt must be fitted so that the pressure SEALS it against the bolt (like a brake cylinder rubber)- try the new seal over the bolt first,you will see a mark on the bolt where the the seal usually sits, it should be a snug fit at this point. If it isn't the bolt should be replaced as the surface may have been worn down by dirt in the by-passing oil - it doesn't take much to start it.
- A better cure if you can afford it is to replace the whole oil filter assembly with a late model "spin on" type.
Personally I think this half inch rubber grommet is the major cause for the bad "top end" engine wear press these motors get. This may sound like a lot to say about nothing much - but if you care about the longevity of your motor
- THINK ABOUT IT! they only cost cents.
By the way, there is an excellent E3 / E9 TECH TIPS page here as well with a hot linked Table of Contents. Go take a look: http://members.aol.com/BMWBavaria/tech.htm
Thaumatrope