Date: 16-Dec-1996 16:21:36
From: Pete Read <pete.read_at_boeing.com>
Subject: Re: <M5><M6> S38 Valve Spring Compressor

Steven Morey, '87 M6 owner, asks:
>Does anyone know a source for a reasonably priced valve
>spring compressor tool for the shim-adjusted valves on the
>old M cars?

Yes, Europroducts 800.850-0325 sells them for about $70. The equivalent BMW tool is about $160. Note that the S38 engine tool and shim information below also applies to E30 M3 engines.

BMP 800.648-7278 has a purchase and rental option: (Sept '95 price list)

1. Purchase kit with tool and 50 assorted shims for $530.

   (Euro M88/3 engine kit is $830)

2. Rent kit above for $70

   Price of each shim used with rental kit $8

M88/3 Engines, Euro M5 and M635CSI

Paul Hahn didn't record the VW/Audi part numbers, but posted the OD measurements of his Euro M635CSI shims to the Mformation digest -- 31mm (30.96mm).

Europroducts Tool, Volvo Shims on S38 Engine

>From Larry Li...
<I purchased the valve tool for my 88 M6 from Europroducts for around $70 and it worked fine. The only problem I had with the tool was that the material was a bit soft and the ridges were not symmetric. This resulted in not compressing one of the valves quite enough to get the shim out. I had to wrap a bit of material around the camshaft to get the tool to compress the valve enough. I had noticed a tool described as "shim pliers" in the ad, selling for $15 but I didn't get it. I ended up prying the shims out with a thin Exacto blade, but next time I think I'll try the pliers. I had read that Volvo shims could be substituted for the BMW shims on the US spec M6 and that Volkswagon shims could be substituted on the Euro M635Csi. I purchased the Volvo shims for around $3.50 each, compared to $13 each for BMW OEM. The Volvo shims have sharper edges so they are a bit more difficult to drop into the valve buckets, but as long as they are dropped straight in, they work fine. I performed the valve adjustment by measuring the lash with the engine cold. I measured the shim thickness on any valves which exceeded spec. The shims from the valves which needed adjustment were of different thicknesses so they could be shifted around to adjust one of the other valves. As it turned out, I may have needed to adjust 8-10 valves, but I only needed half that many new shims. The original shims deviated very little from the indicated thicknesses. For instance,
a 3.75mm shim might measure out to 3.73mm. The conclusion from this is that the shims barely wear. I've read that the shims can be lifted by blowing air across or under them, but I found that to be very messy because of the oil pooled under the shim. Try the pliers.>

Regards,

Pete Read
'88 M5