Hello again,

Just curious if anyone has done the timing chain(and tensioner of course) replacement on the M103 engine. I've read thru the service manual and it doesn't seem to hard, the Haynes UK manual also states that the special chain press tool is unecessary and you can use a hammer and block to press the rivets into place. I've also discovered that I can rent the tool from IMPCO if necessary(seems better to me) My big fear of course is that the chain will slip on installation changing timing. Anyone done this??? BTW thanks to all on the handling posts. Going to replace those rear thrust arms very soon.



Evan

Why are you replacing this chain? This is reportedly one of the engines that does not experience chain failures. If it aint broke, don't fix it.

Have a nice weekend,

lewise
 

Larry said it like it is. I have a 1987 300E with 170,800 miles and I'm not evan thinking about replacing the TC.
If it ain't broke don't fix it.
The long life of all engine parts is faithful oil and filter changes. Not twice a year, but frequent whiether your use conventional or syhthetic moter oil. I change every 3500 miles and have for the life of the car.
My engine has never been opened. Not even for valve guides. The oil consumption is 1 quart per 1150-1300 miles depending conditions.
Good luck with your not changing the TC. Save your time and money for Euro Headlights or what ever.
Happy Trails Beep Beep from Houston.

Donald.
Bye the Bye, throw that Haynes Manual away, it will do nothing but cause you grief.

My '86 300E had 210,000 miles on it when I sold it, it now has had a valve job and all is well 250,000 with no new chain. The tensioner is such that it ratchets into place to take up slack. The chains are short and don't wear that much. I'd leave it be.

Donald,

I think that you and I should collaborate and write the MBZ frequent oil change song. I'll write the lyrics, you write the music. Wha' d' ya' think?

Have a nice weekend,

Larry
 

If the tempo goes with the frquency of oil changes on my end, it wouldn't be a waltz but something a little hotter.
I believe in the changing of the motor oil and filter if you have nothing better to do; no matter the miles just change the oil for the fun of it.
Since I use the cheap spread, I can do it and it doesn't hurt the old purse.

Atsa onaah twooah anah treeah.

Happy Trails Beep Beep from two step Houston.

Donald stepah onah you toes

BenzMac
 

The 300E you sold and had to have the valves ground after, do you have any info on that job?
Since mine is at 170,900 miles and I'm shooting for 200-250,000 miles before the same service, were the guides replaced too and what was the cost?
How about the valves and the seats? Were they useable and did the valve seats get the three angle grind?
Just gathering info so I can start putting a few sheckels in my Piggy Bank.
Happy Trails Beep Beep from Houston
Donald

Donald,

If you're going to R&R the head yourself, $600 or $700 should cover it. My head had to be welded, straightened and valve job including guides. The guy I use has a reputation for being; slow, expensive and good. He comes through on all three counts. My head with all that work from an expensive shop was $500. The gasket set is about $100 as I recall. Allowing for maybe a drive belt or something that you may feel you need to replace while you're in there, and $700 would be a safe number.

Don't forget to get the special translucent blue goo from MB for the U Seal at the bottom of the upper timing cover.

One other thing, you can leave the intake side manifold in place or disconnect everything and leave it on the head. I chose to leave it in place and it worked great for me. My friend the MB tech says it's six of one and half dozen of the other. He usually pulls the intake with the head.

Good luck,

Good questions!

The valve job consisted of new guides and seals and gaskets. I have not had to replace seats or valves. I saw a head that had a seat replaced and it fell out after 10k miles. I would NEVER allow a seat to be replaced.

After the valve job, the engine runs as new again.

No oil consumption.

Thanks Gang
 

I was concerned about the intake manifold. I must confess after twelve years, I haven't the foggiest idea on how to remove the cylinder head. Oh, I've got MB manuals and have studied them but I feel inadiquate. Me a graduate automotive engineer(notice no caps). When the time comes I'll bite the BULL IT.
Happy Trails Beep Beep from lost Houston
Donald

once you do one
 

you will realize it is not that bad Donald. Just pay attention to what you are doing, follow the manuals and take your time.
Jim
'95 E320
'97 CRV

engatwork
 

Thanx Jim, I guess I need a little build up for when it happens.
I've studied my 300 for twelve years, I know every bolt,nut and screw it has.
It is the disassembling my beloved toy that upset me.
I taught in the General Motors Training Centers in the maintenance of the automobile in all parts. I don't know why I have this hang up on my Benz?

Happy Trails Beep Beep from gun shy Houston!!!
Donald, El Cheapo

LOL - Donald I was
 

intimidated until I changed the rear main seal on mine. It was also the 1st rear main seal I have ever changed. Working on the MB makes you enjoy the engineering that much more.
Jim
'95 E320
'97 CRV

Donald,

I understand your hesitation to cut open your baby, even when the time comes you have to do it to make her live.

I felt these engines a little mysterious until the time came that I had no choice. The M103 engine comes apart and goes back together absolutely beautifully. You need to use the right sealer on the upper timing cover to keep the seal from slipping out of place, I don't know any other real tricks to it. I did get a little confused over the cam sprocket bolts, turns out their torx.

You will enjoy the job very much,

Book time estimates
 

The chains are noted in my computer at work as a non wearing/ rarely wearing item ( never seen that in reference to timing components). I can say that mine at 88K is BRAND new looking and did not need replacement. Book estimate time is 10.5 hours which is alittle outlandish but as I think about it, not unrealistic. I'd leave it alone personally, I doubt it has worn, I've heard stories of 200k.

BTW, dont let the chain slip, it'll be a pain to get back into time and it is an Interference engine ( piston impacts valve) if it is out of time.

Good luck

Jason M.

86 300E 88k miles
99 Crew Cab Chevy Dualie 7.4L