Lower rails do break
 

'89 560 SEL, 110,000 miles. Box of parts to do upper rails and chain in the garage for a year. Scared to try. Rough idle, heavy oil consumption which I thought was due valve seals fouling plugs, parts in the same box in the garage. Two months ago, she kicked and died shortly after starting one morning. Chased fuel issues for a time, then Craig Morris (AFMCorp, regular poster here) pointed me to timing. Pulled right valve cover, aligned cam marks and determined 14 degrees of stretch. Gathered the courage....

Since the right cover was off, did the upper rail there, really smooth job. Pulled the left cover and immediately saw rail fragments all over the place. Both upper rails gone. Cam nearly 90 degrees late at 1 TDC. Spent Saturday fishing rail pieces and beginning tear-down for probable removal of timing cover. Removed lower oil pan and was able to piece together most of the two upper rails, but had a large chunk that didn't seem to belong--darker, less brittle. Started checking broken pieces for part numbers, and found 3 different numbers. Checked Fastlane, and the third number was from the LOWER LEFT rail. Definitely have to pull the timing cover now. Ran out of steam at the crank bolt last night, and no time to work today. Seems to be one tight bolt.

Now for some questions.....
When the new chain is eventually rolled in, should the cam marks on both sides line up when she's at #1 TDC?

Is the purpose for loosening the upper oil pan (3 to 4 turns per bolt according to alldata) just to allow the cover to clear the bottom of the head?

Engine just gave one backfire and died, no cataclysmic metallic banging when she went. Has turned without interference since. Any chance that no valves were damaged??

Anyone want to came and remove that blasted crank bolt??

Am I crazy to try to make her run again? Should she become a donor?

Thanks for listening.

crankbolt
 

I just replaced all rail etc.. on my 88 190e. I know they are very different cars but, what i did to remove my crank bolt, was I stuck a wooden handle of a hammer into the flywheel area to keep it from spinning, then I had my breaker bar on the socket which was over the crank bolt. That wasnt cuttin it, so i put a 3.5 foot peice of copper pipe over the breaker bar, and WOW the bolt started moving. I was pretty impressed on how well this pipe worked for me. So give that a try. If you have room to get an impact wrench in there then give that a try. I couldnt fit the impact wrench between my a/c condensor(?) and the bolt.


On my 4 clyinder this was a pretty big job, I had more bolts off then when i swapped out engines.

Thanks
 

Flywheel access is too small for hammer handle, but now that you mention it, i may be able to wedge the scredriver i was trying to hold by hand (while my son tried to turn the bolt) with a 4x4. Going to pick up some penetrating oil in the morning and stop by a few times during the day to shoot it with that too.

Not enough space for impact wrench, might an air ratchet offer enough torque? I'm new to air tools, have only an impact (old, marginal) wrench, but willing to accumulate.

Thanks again.

I dont think that an air ratchet would product enough torque to turn that bolt. It's the contstant pressure and pounding of the impact wrench that make it good for getting out stuck bolts.

Try sticking that screwdriver in there and see if that will hold the flywheel. Or see how much the dealer tools costs, maybe its not too much? And give a try at the pipe trick. I was amazed by how well it worked.

I did a cover off on the Euro 420 engine that was put in my Euro 500SE. And I'm sure glad I did as the bolt that hold the largest of the bottom rails backed out till stopped by the cover allowing the rail to sit at a slight angle ,it was paper thin with very deep grooves.I also replaced the oil pump chain while cover was off.

I used a large screw driver and a pair of needle nose vise grips to hold the screw driver that was wedged in one of the holes on the bottom of the bell housing catching a tooth on the ring gear,then put a long steel pipe on a breaker bar with a new 6 point 27 mm socket and pulled hard.
Yes you drop the upper pan on it's bolts to give a little clearance at the heads, and both cams should be on their marks when at TDC on the compression stroke.I cycled the engine many times by hand double checking before I started it, if you take the oil pump out you have to fill it with oil before reinstalling.I highly suggest you have a manual that shows the cam marks etc, I was a fool and did the job with out one a friend gave me the torque specs and away I went.If the engine last another hundred K it will be easier the second time...........
William Rogers.......

heres a photo, sure a lot of stuff to take off and put back on.were your valves ok?........
William Rogers.......

Great photo
 

William,
That is a much clearer picture than the grainy b/w's on the cd or alldata. Most everything is off already, going to get the crank bolt out tonight, one way or another. Can only hope the valves are all right, is there any way to know for sure before reassembly without pulling the heads? Do you recall if the pivot pin for the tensioner rail the same as the other pins?

I recall all pins being similar .If you bent valves take the drivers side valve cover off and with cam lobes at their low side on exaust valves you should be able to see if they look ok or not. If you type bent valves into search there are many threads that will help.It sure seems that there would be a better material for the rails.........
William Rogers........

I know i have a different car but my pivot pin for the tensioner rail, was a little larger and was not tapped.

What am I missing??
 

Crank bolt came out with ease, I must have just been whipped Saturday when I tried it. Now...

The harmonic balancer (marked with timing marks) won't clear the bracket for the a/c belt tensioner. Removed the pulley assembly hoping it might allow room to cock the balancer past--no luck. There is no mention of removing condenser mounting plate, but that's what it appears must happen. If so, there is an allen bolt behind the suspension pump that looks almost impossible to get to without removing the front of the hydraulic pump. Getting frustrated, time for ice cream and some rest. Any ideas??

To jrbnc--now that you mention it, i recall that the pin for the "banana" rail is removed by canting a bolt in the opening of the pin. Thanks.

To William--The broken piece of the lower rail that I fished out is not nearly as brittle as the upper. New lower rails should be here tomorrow (from Phast Phil of Fast Lane). I'm curious to see if it appears to be the same material as the uppers and the oil bath has kept it more supple.