Free 1991 420SEL - Page 2 - PeachParts Mercedes-Benz Forum

BobK · #16 02-06-2005, 10:47 PM

Do a good cooling system flush and put in the proper MB stuff instead of green? I second the motion for the big rubber boots between manifold halves. Another idea would be to replace all the rubber hoses around the injectors. All that stuff gets hard and leaks. Bunch of little vacumm leaks. Shame you can't easily test the injectors. When I replaced the injectors on my 560, I replaced all the little rubber hoses, the injector seats and seals, and any other vacumm pieces that looked bad or seemed inflexable. Helps on driveability. Pain to do later.

newr · #17 02-07-2005, 01:31 AM

The manual instructs to turn cylinder 1 to TDC which I did (picture 1). The woodruff key on camshaft should point up (picture 2). I am confusing as to which direction UP it should be? Should it be perpendicular to the ground (pictures 3) or perpendicure to the head (pictures 4). Another question is should both woodruff keys on camshafts point up?

I only put back the chain cover and old water pump temporaty for setting the TDC.

THANKS.

AF300E · #18 02-07-2005, 06:29 AM

I thought only 380 and 560 had Alloy blocks? We never got the 500 motor in the w126 in Oz so I don't know about it.

126nut · #19 02-07-2005, 12:24 PM

Quote:

Originally Posted by AF300E

I thought only 380 and 560 had Alloy blocks? We never got the 500 motor in the w126 in Oz so I don't know about it.

The 420 blocks are alloy as well.

Maybe you're thinking of the earlier 4.5 litre V8's?

BTW newr,

Looks as if you're doing an in-frame job on yours but if for any reason you end up pulling the engine, don't get the ring gear and flex plate assemblies mis-oriented upon reassembly. The engine will run like ca-ca and you will go nuts trying to figure what you screwed up on. (speaking from experience)

newr · #20 02-07-2005, 01:31 PM

Quote:

Originally Posted by 126nut

BTW newr,

Looks as if you're doing an in-frame job on yours but if for any reason you end up pulling the engine, don't get the ring gear and flex plate assemblies mis-oriented upon reassembly. The engine will run like ca-ca and you will go nuts trying to figure what you screwed up on. (speaking from experience)

Chas, The engine was pulled out and thanks for the pointer regarding the flexplate and ring gear/plywheel. I removed them as one piece so there will be no mistake putting it back as they have to line up the the dowel.

Anyone else can help me with the camshaft TDC issue? I am very DESPERATE.

126nut · #21 02-07-2005, 10:21 PM

I have never paid any mind to where the woodruff key is.

Just get the cam gears on and look for the notch on the first cam tower and the mark on the cam gear, get them lined up and all is well.

AF300E · #22 02-08-2005, 01:09 AM

Also, if you do remove the engine and take the alloy sump off it, make sure you use a straight edge when you refit to line it up with the block or it can cause vibration when it doesn't tension correctly.

theairboy · #23 02-08-2005, 02:36 AM

Cant tell for sure on the key but if its in the correct position the cam will have no slop pushing on the #1 cyl. I know your question is only about 10-15 deg. but it should be noticable.

Yes like they said and all the vacume lines below the intake too.

newr · #24 02-10-2005, 11:45 AM

The manual got me confused (yeah, blame it on the manual

) . I think I have figured it out just like Chas had mentioned. It turns out that the timing mark on the cam is the same position as the woodruff key. There is also timing mark on the camshaft first bearing/tower which I did not pay attention. Right now, the cylinder #1 is at TDC and both camshaft timing marks line up with the bearing/tower marks so it should be good to go. I will turn the engine over by hand a few times and see if everything is in sync.

Thanks

newr · #25 02-10-2005, 11:49 AM

Quote:

Originally Posted by AF300E

Also, if you do remove the engine and take the alloy sump off it, make sure you use a straight edge when you refit to line it up with the block or it can cause vibration when it doesn't tension correctly.

Can you please elaborate more on this? Excuse my ignorance of the terminology, but what is the sump alignment? what is the alloy sump?

THANKS

AF300E · #26 02-10-2005, 05:59 PM

Better to ask and do the job once eh?
When you refit the large alloy sump that allows access to the big end, make sure that the face that meets the bell housing on the transmissin is in line with the face on the engine block that meets the bell housing.
Otherwise the engine tensions incorrectly against the trans and can cause a vibration that is almost impossible to diagnose.

newr · #27 02-10-2005, 07:02 PM

Quote:

Originally Posted by AF300E

Better to ask and do the job once eh?
When you refit the large alloy sump that allows access to the big end, make sure that the face that meets the bell housing on the transmissin is in line with the face on the engine block that meets the bell housing.
Otherwise the engine tensions incorrectly against the trans and can cause a vibration that is almost impossible to diagnose.

Got it.

newr · #28 02-17-2005, 11:46 PM

After the timing marks were all lined up (thanks for clarifying), the engine was turned over by hand a few times without interference.

. This was the hicup I had ran into so far that slowed me down waiting for clarification . I am crossing my fingers and knock on wood that I won't run into anymore problems.

. So far every nuts and bolts have been put back exactly where they came from. Thanks for the tip on this board somewhere that mentioned to lable and bag parts and nut/bolts together so reinstallation went pretty quick. Imagine if I had not done that I would be still be figuring out which bolts/nuts go where.

Attached are couple pics and the 2nd one is where I am at right now.

newr · #29 02-24-2005, 02:30 PM

The engine is now ready to go back in the car.. Wish me luck.

andersbenz · #30 02-24-2005, 11:29 PM

newr,

Way to go. All the best with the installation and start up!