[W126 Coupe] 560SEC top-end rebuild

[Gerry Van Zandt]

The thought is much appreciated. I inspected the lobes of the cam after removing the right-side head last night, and its' profile is noticeably rounded off compared to the other lobes on that cam. Not to mention the scoring, which would require polishing it out and taking off even more material, not to mention perhaps the hardened surface.

A close friend who owns a shop in the SF Bay Area has around 20 spare used 560 cams in stock from cars he's disassembled over the past 20 years, as well as around a dozen new units in stock. He's going to send me a used one for next to no cost. I'd rather use a factory part (even used) than the TRW stuff that's commonly available on the aftermarket (i.e. Worldpac). Benz wants nearly $800 for a new cam so I'm happy to use a used one in good condition.

Rocker arms .. yes, going to have to replace all of those. They're not all that expensive, so no worries there.

I'll be taking the heads and intake manifold parts to my machine shop in a few hours, in downtown Houston. Last night after removing the right-hand head and examining it closely, I found that a chunk broken off in the hole where the chain tensioner goes into the head. From all appearances, this chunk is probably the result of a casting flaw, and was broken off many years ago. It's not a critical flaw as there is plenty of sealing surface left for the chain tensioner to sit on, but I'm going to have the shop weld it in order to repair it.

I took a couple of close-up photos last night and you can see them on the Facebook photo album link I posted in my previous message.

The exhaust manifolds are going to a local shop to be coated with Swain Tech, per Jonno's recommendation. This shop is very close to my office so I'm happy about that.

The machine shop doing my work comes highly recommended by many Houston area indy shops and dealerships, and does a LOT of MB and BMW block, crank and head work. Their name is Scroggins Machine and you can see them at www.scrogginsmachine.com

Regards,
Gerry

 
On Wednesday, March 17, 2010, at 11:15AM, <mbcoupes-request at mbcoupes.com> wrote:

>

>I'm not sure just how bad the cam is that prompted this work, but if you 

>can't find a new cam at a reasonable price, you might check in the 

>possibility of getting it reground.

>