M Roadster Valve Clearance
Last Modified Jan 22, 2012

Tools

There are a few special tools needed when doing the valve clearance check.

The most important one is the BMW valve shim remover/installer, which has a magnet that helps prevent the user from dropping a shim into the crankcase via one of the oil galleys or into a cylinder via a spark plug hole (if you're foolish enough to not plug those holes). This tool is BMW 83.30.0.493.743, and was previously BMW 90.88.6.114.400.

On some S54 engines, a special tool is needed to turn the engine via the crankshaft. It fits over the bolts on the vibration damper. This tool is BMW 83.30.0.491.056, and was previously 90.88.6.115.100.

Feeler gauges are also needed. The specification for valve clearance is .18mm to .23mm for the intake, and .28mm to .33mm for the exhaust. I've not found metric feeler gauges with these exact sizes, but .18mm is .007", .23mm is .009", .28mm is .011" and .33mm is .013". The inch sizes are easy to find.

There are really 2 different uses for the feeler gauges. The first is to measure the existing clearance, for which I could use better resolution than what's available in off-the-shelf feeler gauges. The second is to check the clearance when a new shim has been installed, and step-ground ("go/no-go") feeler gauges are near ideal for this task if the range is correct. I bought some Eastern Industries step-ground feeler gauges (FG-22-STEP), but the blades are straight and somewhat short. I will probably bend the ones of interest. I also bought the Eastern Industries FG-26-4-45 set, which have 4" blades with a 45-degree bend but are not step-ground. And since my older sets of feeler gauges have seen better days, I also bought Eastern Industries FG-25-3-SS which are stainless steel flat feeler gauges with 3" blades.

I requested a quote for custom feeler gauges, but have not received a response. I'll try again soon.

A micrometer is needed for measuring valve shim thickness. I use my Mitutoyo digital 0-1" micrometer.

Parts

The obvious parts needed: valve shims in various thicknesses. There are two options here: take all the measurements and buy only the shims you need, or buy the 11.34.0.031.525 shim set. I prefer the latter option. The list price for the shim set as of January 21, 2012 is $466.46. It can be found for around $375 online.

A slew of gaskets are needed:

There are a number of places where you can buy the shim set and the gaskets as a kit. I bought mine from ECS Tuning for $445.00, and it also included the valve shim remover/installer mentioned above. Turner Motorsports has the same kit for $499.

Consumables

The main consumable needed is a sealant for the valve cover. This works in cooperation with the gasket. BMW recommends Drei Bond 1209, but has 3M 8661 listed as suitable substitute. I have 3M 8662, which is the same as 8661 but is black in color (8661 is clear). I also have Permatex 85815, which I prefer to use for these types of applications due to its high heat resistance (good to 600F) and the fact that it's easy to lay down an even bead with the squirt can.

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