Dr. Frankenstein at work – The head transplant is completed
 

Finally Done. Jeez, that was a lot of work.

She fired right up & settled right down into a nice melodic tick tick ticking idle. I let her idle for about 30 minutes with the cooling system flush, then changed the oil and now she’s cooling off – I need to drain the flush out of the cooling system. Once I have that done, its time to go for a drive. The only question is whether or not to take my toolbox with me. Not taking it with me implies a certain amount of foolhardy overconfidence & invites Murphy along for the ride. Taking it with me seems like a concession - a prelude to defeat; but maybe it’ll keep Murphy at bay. Decisions, decisions…

I am continually impressed with how straightforward these cars are to work on. It seems as though the engineers at Mercedes-Benz took a completely different approach with the 123’s compared to some of the earlier designed cars (such as the 107’s, which can be a real pain in the ass to work on).

R&R’ing the cylinder head is not really all that difficult; time-consuming, yes -- frustrating, no. While it's not exactly child's play, I really believe that this can be tackled by most do-it-yourselfers. All it takes is a little fortitude to jump right in, very few specialized tools, and the patience to follow through with the little details. There are a few things that can be rather tedious, but there are not really any “gotcha’s” to look out for, and this whole thing was accomplished with a minimum of cussing.

If anyone is going to be doing this, it is a good time to do a lot of little preventative replacement items. I did the oil cooler lines, all of the little cooling system hoses, motor mounts (again), engine shock absorber mounts, front crankshaft seal, timing chain & rails, and adjusted the injection pump timing.

I’ve been driving the 450 & 500 around while working on this one, so it is going to be interesting to see if I can (still) be able to notice a difference in how it runs as compared to before. (Discounting the long cranking, misfiring, & billowing clouds of smoke, of course).

Wish me luck – I am not a member of AAA anymore, so any towing expense is out of my pocket…:eek:

RTH

Best of luck. But it sounds like everything went well so you likely won't need it. Re: this being a job for DIYers, what types of other projects have you attempted prior to this one as far as mechanical difficulty goes? Just curious as this may be something I may attempt one day.

way to go RTH
 

It is my feeling that if someone can do a brake job - including calipers/rotors on the W123 then they are competent enough to do the cyl hd R&R. Did you do the timing chain guides at the bottom of the engine area too?
When I first ran the 240D after the rebuild I kept driving around a 5 mile perimeter from the house for the first 25 miles. Just try to carry a cell phone with you :)
Once I get the 240D where I want it I am probably going to pull the head on the 300D to see what I have. My plans were to get to 250k before doing it but it is based on when I take the 240D down off of the jackstands - doing brake hoses (at the calipers) and front wheel bearings this week.

I agree completely with you. This is not rocket science. Patience, diligence, and common sense is all it takes. Oh, yes – some tools will help. And just a bit of mechanical aptitude.

About the rails: I only replaced the banana (tensioner) rail & the upper guide. From what I understand (not saying much there ;) ) the lower guides in these engines are not usually a problem.

I've gotta run - time to go turn my engine into shrapnel (check my other post)

RTH