M103 Head Bolts - Curious About Bolt-Washer Combination
 

I'm doing a head gasket job on my brothers '89300SE (W126). The head bolts are the newer/shorter version (flange type to be used without washers)...BUT washers are in place (the 5 mm space type that were used with the older/longer bolt versions).

I'm just curious if anyone ever ran into this before. It appears this is the first time the head has been off the car (gasket is Elring, some other indications (intake valve seals are the old metal collar version), etc). So, I'm thinking this was done AT THE factory. Everything I've ever read indicates when they made the change (circa 1988?) they made it completely (i.e. changed to shorter bolt and dropped use of the washer simultaneously).

Anyway, just curious if anyone ever came across this.

As for reassembly, my plan is to omit use of the washers (once I've checked depth of threaded hole on block, of course).

Yes, the newer bolts were exactly the same threaded length (new 102MM) as the older bolts (with washer).

MB Doc,

Thanks for the post. Actually, I did already know that the long/old style bolts (105mm), when used with washers, were replaced by the new/short(102mm) bolts, and the thread length was the same. I guess I didn't clearly write my first post.

What I found on the M103 I'm doing is it had the new/short bolts, but ALSO had the washers. And since it seems to me this is the original head gasket, I'm concluding this arrangement (new bolts with washers) was done at the factory. WHICH is something I didn't think happened.

I was just curious is anyone had ever come across this arrangement before.

Page 2 talks about it here:
http://www.w124-zone.com/downloads/MB%20CD/W124/w124CD1/Program/Engine/103/01-4050.pdf

Basically the new bolts don't need the washers from the old.

Don't forget to lubricate the bottom of the new headbolt 'washer', which is included in the new bolt, which is a 102 part. I did a valve job on my M103 89 300SE W126 when I still had it.