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  #1  
Old 08-26-2006, 05:28 PM
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OM 603 timing chain........screwup.......

Today was the day for the timing chain replacement. Thought the neighbor would be home to help me so I got everything torn apart, got the old chain apart, then he tells me his wife wants to go to the lake. WELL, the only person left to help was my 5 year old son. I figured I'd let him in charge of one thing - pulling out the old chain. I figured I'd keep a vice grip on the cam pulley, and just turn the crank, then move the vice grip. Well, the vice grip left go and the chain pulled down but I caugt it before it went in, but the old chain being oily, he left go of the damn thing I was able to fish it out with a magnet, but when he left go it sounded like something under spring pressure let go. Anyway, I got it out, and started to turn the crank again, but this time the cam pulley wasn't moving, so something down below slipped out of place and there must be slack in it somewhere. What the hell do I do now?? I still have the chain clamped to the cam pulley, back where it orgianlly was. Any advice would be GREATLY appreciated!!!

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Old 08-26-2006, 06:29 PM
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Upon further inspection, it appears as if when the vice grip let go the IP gear pulled the chain down into the engine (it only went a few inches before I caught it) and it slipped off the crank gear. Does that sound right? Is it the IP gear that is under tension? Like I said, the chain is back in the same position on the cam gear, which is at TDC. The chain still seems to be under tension on the drivers side, so I am assuming that it didn't slip off the IP gear. The crank pulley is pretty much at the same spot it was before all this happened. If I drop the oil pan, would it be possible to pull the chain back onto the crank gear the way it was? I am sure this would be nearly impossible thought, right? Because I can't be sure the crank pulley is in the same spot. I did move it to see if the chain would pull through, but that's when I noticed the cam gear wasn't moving, so there is slack in the chain. I then moved the pulley back to the spot where it was. Please guys, I need any advice you may have.
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  #3  
Old 08-26-2006, 06:37 PM
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I hate to say it but if it was me I would take the front of the motor off and start from scratch.This is something that must be exact and I wouldnt take the chance of losing a good motor.I truly hope someone else has a better answer to your dilema ,good luck.
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  #4  
Old 08-26-2006, 06:41 PM
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You've got a lot of work ahead of you.

The problem is that you don't know the timing of the cam or the IP with respect to the crankshaft.

So, your only choice is to start from the beginning.

If the new chain is installed, first see if the engine will rotate. If it does, then you need to set the crank damper to 0 and see if the marks on the camshaft tower are aligned. If they are close (and they will be if you can rotate the engine), then you'll need to adjust the camshaft until they are almost dead on.

Once that's done, then the IP will need to be checked to see if you still have that timing. If the chain came off the IP timer (unlikely), then it's even more of a chore to get it corrected.
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  #5  
Old 08-26-2006, 06:45 PM
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This is exactly the situation of why I'd rather pay the extra money to have a MB shop do a chain job for me.

The chain is one of the only things I prefer not to mess with. I scared the begesus out of myself when I almost dropped the cam gear installing the offset woodruff key.

All I can say is get a flashlight and look very hard for anthing out of place.
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  #6  
Old 08-26-2006, 06:48 PM
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All I can say is I really feel for you and hope you get it worked out-let us know.
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  #7  
Old 08-26-2006, 06:50 PM
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Well the thing is I never even began the pulling of the new chain trough. Everything is in the same spot where it began, I never moved the crank or the cam gear, so I know that the chain is at the same spot on the cam gear because the master link is at top of the gear. I don't think the chain came off the IP gear, because it looks like the chain guide would prevent that unless it had fallen the whole way into the engine, which it didn't. So basically I can pull the old chain on the passenger side up to the cam gear, but it's about 2 inches short, so I guess I can assume that there is about 2 inches of extra chain on the drivers side of the crank gear. I know the crank pulley is within 1/4 inch of where it was before this happened. My theory is if I can access the bottom of the crank gear, I can get the chain taught again and it should be able to meet up with the other section at the cam gear. So what's the best way to access the crank gear? I looked at the oil pan, and didn't realize it was so big. It looks like I'd have to pull the sway bar, and the little box attatched to the side. Is the gasket for the pan reusable? If not, can I use a liquid gasket? The problem arises that it's the weekend, and getting a factory gasket would not be possible for a few days.
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Old 08-26-2006, 06:55 PM
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I wish I could go back in time knowing what I know now. If I had that opportunity, I would have put a vice grip on the chain that my son was pulling, that way if it slipped it wouldn't have dropped. Also, I screwed up royally by taking both grips off the cam gear at the same time. I should have kept one on the chain at all times, I think the ideal way to do it is to put a grip on the passenger side, turn the engine until that grip hit's the drivers side, then put another grip on the passenger side and only then take off the divers side grip.
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  #9  
Old 08-26-2006, 07:07 PM
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Quote:
Originally Posted by Jmana View Post
Well the thing is I never even began the pulling of the new chain trough. Everything is in the same spot where it began, I never moved the crank or the cam gear, so I know that the chain is at the same spot on the cam gear because the master link is at top of the gear. I don't think the chain came off the IP gear, because it looks like the chain guide would prevent that unless it had fallen the whole way into the engine, which it didn't.
OK, take a step back for a moment.

Why do you believe that the chain has come off the crankshaft if you never did any pulling of the new chain and everything is in the same spot as where it began?

I don't believe that the chain will fall off the crankshaft on an OM603, so, your issues might simply be that the camshaft has rotated slightly and put slack on the drive side of the chain, thereby leaving you with insufficient slack on the tensioner side.

If you marked the chain carefully and the sprocket carefully, then rotate the camshaft and sprocket counterclockwise so that you can connect the ends of the chain.
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  #10  
Old 08-26-2006, 07:18 PM
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Well, I know the camshaft didn't move, the mark on the gear is still matched up to the mark on the tower. The reason I thought it came off the crank gear is I started to turn the crank pully, and the cam gear did not move. In fact I turned the crank pully about 30 degrees and still no movement, so then I turned the pulley ccw to get back in the same spot it was, which is when I realized the two ends of the chain weren't meeting. So apparently the chain can slip off the crank gear. Now that I am looking at the oil pan, I am realizing that's not going to be an easy job at all. Is there any other possibilities here?
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Old 08-26-2006, 07:45 PM
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Quote:
Originally Posted by Jmana View Post
Well, I know the camshaft didn't move, the mark on the gear is still matched up to the mark on the tower. The reason I thought it came off the crank gear is I started to turn the crank pully, and the cam gear did not move. In fact I turned the crank pully about 30 degrees and still no movement, so then I turned the pulley ccw to get back in the same spot it was, which is when I realized the two ends of the chain weren't meeting. So apparently the chain can slip off the crank gear. Now that I am looking at the oil pan, I am realizing that's not going to be an easy job at all. Is there any other possibilities here?
No, you don't even want to consider removing the oil pan..............

OK, if you have the cam pulley on the marks and it did not move, simply rotate the crank pulley until the "0" mark is right on the indicator. Then pull up on the tensioner side of the chain and see if it will engage the teeth of the crankshaft. You may need to rotate the crankshaft slightly when you do this.

From now on, it's a two man job..........a five year old is not going to cut it.
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  #12  
Old 08-26-2006, 08:07 PM
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Yeah, no kidding! Unfortunately we moved here recently, so we only know the one neighbor, and like I said, his boating trip takes precedence over my trouble! Well, I think I may have it okay now. Whatever is putting tension on the chain was screwing me up. I took the chain off the cam and gave it some slack, and then was able to pull out the chain on the passenger side, then pull back on the drivers side chain to get it back on the sprocket. I was able to meet up the two sides, but then started to wonder if I was still at the same location on the sproket. I think I was, and was able to pull the new chain in with no resistance (other than that of compression). If it was off a tooth, wouldn't it have stopped moving? Is there any way to tell if it's off before I put the master link on permanent? Also, I was figuring that once I got the new one in, that it would end up at the same spot on the sprocket as when I began, but it didn't. Instead of the mark on the gear being straight up, it is now pointing to the drivers side of the car. Is that normal? The crank pulley is also not where it began.
Here is another question:
Before I began, I had the cam gear mark lining up with the mark on the tower, and the plastic thing on the crank pulley was about 20 degrees to the right. I don't know what that all means, but I was under the assumption that it was also supposed to be straight up and because it wasn't, that it meant the chain was stretched. Well, now that I have the new chain in, the crank pulley mark still doesn't line up with the cam mark. What all does that mean? Sorry, but this is my first timing chain experience.
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Old 08-26-2006, 08:17 PM
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Quote:
Originally Posted by Jmana View Post
If it was off a tooth, wouldn't it have stopped moving?
The camshaft can be off by one tooth and the engine will still rotate.

Quote:
Originally Posted by Jmana View Post

Is there any way to tell if it's off before I put the master link on permanent?
Yep, put the side plate on and put the tensioner back in and rotate the engine at least two revolutions. Then stop with the marks on the cam tower aligned. Read the crankshaft damper and report back with result. Take a photo and post it if you can't read it.

Quote:
Originally Posted by Jmana View Post

Also, I was figuring that once I got the new one in, that it would end up at the same spot on the sprocket as when I began, but it didn't. Instead of the mark on the gear being straight up, it is now pointing to the drivers side of the car. Is that normal? The crank pulley is also not where it began.
I'm not with you here. With a new chain, there is no "spot" on the sprocket. If the engine moves a few degrees forward, then you'll have a different position for both the cam and crank sprockets.

Quote:
Originally Posted by Jmana View Post
Here is another question:
Before I began, I had the cam gear mark lining up with the mark on the tower, and the plastic thing on the crank pulley was about 20 degrees to the right.
There is a small metal tab, about 15 degrees to the right, that is the crankshaft position tab. You need to read the degree wheel relative to this tab. If you can't read it, or don't understand what to read, you'll need to take a photo and post it.
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  #14  
Old 08-26-2006, 08:25 PM
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What I see on the crank pulley is 3 plastic looking things. 2 rectangular ones with a circle in the middle.

What I meant about the spot on the sprocket, is where I took the old chain apart was right where the mark on the cam gear was. But when I got the new one in, where they joined together was not at the mark.

I'll turn the engine over a couple of times, and let you know what I find.
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  #15  
Old 08-26-2006, 08:31 PM
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Quote:
Originally Posted by Jmana View Post
What I see on the crank pulley is 3 plastic looking things. 2 rectangular ones with a circle in the middle.

What I meant about the spot on the sprocket, is where I took the old chain apart was right where the mark on the cam gear was. But when I got the new one in, where they joined together was not at the mark.

I'll turn the engine over a couple of times, and let you know what I find.
The loss of tension on the chain may affect your observations.

As you planned, see if the engine will rotate.

I'm not familiar with the plastic looking things.........you may need to take a photo.......or someone who has a similar setup will respond.

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