Timing chain fun - PeachParts Mercedes-Benz Forum

rg2098 · #1 10-01-2006, 12:17 AM

Heh.. Here's my latest story.......

Friday late afternoon, have the rest of the day off and the fiance is at work. Alright lets tackle rolling in a new timing chain in my 300. Sounds reasonable right? Well after reading the manual, I forgot to remove the tension on the tensioner and as soon as I popped the pin on the chain it exploded apart and dropped where, you guessed it, into the engine. Wait it gets better, so I can see the end right below the upper guide rail, so lets remove the guide rail so I can use a magnet to pick the end of the chain up. Go to hardware store and buy $5 in washers as a makeshift pin puller (I cracked the guide and did this about 6 months ago installing an offset key in the cam). Heh.... here's the fun part..... I literally sheered the pin holding the guide rail right where the threads stop. By this point I had also cracked my droplight housing in half as well. After an hour with vice-grips and a hammer I was able to get the pin to slide out.

I'm going to drop the lower pan this week and fish the other end of the chain back up, with some luck everything should stay in time and I can just roll the new chain right in. The only part I worry about it links from the chain inside the engine as it fell down. I hope everything is sitting in the pan.

No job is ever easy, at least it's nice having a surplus of vehicles around to drive.

Hit Man X · #2 10-01-2006, 02:11 AM

Don't work when tired.

Alastair · #3 10-01-2006, 08:39 AM

Did something very similar when I did my chain some years ago....

I was able to fish out the link with a magnet on a long pole--It was sitting in one of the bottom sprocket teeth....

I dropped the chain in there then as well....

Luckely the small and strong magnet did the job again!

Great 'get-you-out-of-trouble' tools Magnets!

rg2098 · #4 10-01-2006, 09:26 AM

Quote:

Originally Posted by Hit Man X

Don't work when tired.

I did a trans swap on that same car from 8:30pm to 2:30 am myself, without a hoist or anything like that. Then drove it to work the next day.

Hit Man X · #5 10-01-2006, 09:30 AM

I work on my cars from midnight to 6am all the time. Not a big issue for me.

TheDon · #6 10-01-2006, 09:45 AM

tchain job is a 2 person job.. what were you smoking?

P.E.Haiges · #7 10-01-2006, 12:39 PM

rg2098,

I always clamp the timing chain to the cam sprocket before I separate the chain. This way it never gets away. I once rigged up the chain to the ceiling with rubber bands cut from a tire tube so I could remove a head with out losing timing.

I'm not sure if U can get at the chain by removing the lower pan. Good luck. I have used coat hangers to get out a broken chain.

Its easiest to replace the chain with 3 people but a minimum of 2 might work in a pinch. One to turn the engine, one to feed the chain over the cam sprocket and one to pull out the old chain. Last time I did it, my wife and daughter helped and it went without a hitch.

P E H

Brian Carlton · #8 10-01-2006, 01:01 PM

Quote:

Originally Posted by P.E.Haiges

Last time I did it, my wife and daughter helped and it went without a hitch.

P E H

........made the wife crawl underneath and turn the crankshaft bolt.......did 'ya........?

#9 10-01-2006, 01:43 PM

Since the W123 is a double row steel chain, and MB sell offset woodruff keys to adjust for stretch up to at least 5 deg., does the timing chain even need preventive replacement? I thought the consensus was No.

Brian Carlton · #10 10-01-2006, 01:48 PM

Quote:

Originally Posted by lifer

Since the W123 is a double row steel chain, and MB sell offset woodruff keys to adjust for stretch up to at least 5 deg., does the timing chain even need preventive replacement? I thought the consensus was No.

The consensus is "no"........but........some folks do it anyway..........and you can't stop 'em.

rg2098 · #11 10-01-2006, 03:45 PM

I have 8 degrees of stretch on the chain, plus its cheap piece of mind. For the record I am not doing this myself, but my father is here as well. With just a few hours of work everything is all set and the new chain is in place. I was able to fish the old chain up and roll the new one in like nothing happened. I'm just waiting until Monday to order a pan gasket and guide rail pin.

rg2098 · #12 10-01-2006, 03:46 PM

Quote:

Originally Posted by TheDon

tchain job is a 2 person job.. what were you smoking?

I find this extraordinarily offensive, I do not smoke and never will. I have had too many friends / family die from smoking related issues.

TheDon · #13 10-01-2006, 03:47 PM

Quote:

Originally Posted by rg2098

I find this extraordinarily offensive, I do not smoke and never will. I have had too many friends / family die from smoking related issues.

dude.. its a phrase. sorry for your loss.. but its a phrase... life goes on...

psfred · #14 10-01-2006, 07:49 PM

Bend a hook in some coat hanger wire to fish the chain up -- BTDT, have dropped both ends repeatedly and still came out fine (chain will not jump on the injection timer, thank heavens!).

You cannot reach the chain from the bottom since it doesn't drop down that far, it's lying in the chain case on top of the crank. Just fish the free end up.

Wire ties are the way to go....

Peter

P.E.Haiges · #15 10-01-2006, 08:40 PM

Brian,

Nope.

I can't remember if it was wife or daughter that turned the crankshaft but neither of them had to crawl under the car. One of them walked down the steps and into the grease pit.

P E H