RWDlifer

JPman, just to be sure, you're checking TDC with the cylinder closest to the front of the car, right? Sorry for the asking the obvious....

RWDlifer

I can't figure out how you managed to feed the chain around the crank pulley without moving the cams....was there any resistance?

jpman

RWDlifer yes sir. Checking with cylinder that is closest to the front bumper of the car. No worries, the simple questions are sometimes the best ones, and at this moment anything works.

jpman

I basically attached the new chain to the old one. My dad me and brother were there. There was no tension with the tensioner, so I basically slackened the chain as much as possible and opened both sides of the chain or extended them as far as possible from the cam gears, in other words, as close to the sides of the engines and my brother rotated the crank pulley by the nut to draw in the chain through the bottom sprocket. Basically the same idea as the mercedes document, without the movement of the valves. When that was being done, there was no metal noises of hitting against valves, or hard resistance. If at the moment we would have felt something, we would have stopped immediately.

This is essentially Killerpancakes method mentioned in joggers thread in page 9 I believe.

"After removing the tensioner, the time comes to build up some courage and break the old chain. To break and rivet the chain I had a tool designed for a larger type of chain. I was able to make it work with a significant amount of MacGyvering, but I would HIGHLY recommend having a proper tool for the type/size of chain here. I then very loosely/temporarily riveted the new chain on to the end of the old one and loosely fished it through. Do NOT just pull the old chain out - you definitely want to use it to fish the new chain through, otherwise the lower timing chain cover would likely also have to come off to install the new chain around the crank."

That was quoted from his method.

VVF

Jpman, I think what that means is that Pancakes did not rotate the crank or cams - he just pulled the chain through. (if it is possible that is...)

Correct me if I am wrong, but Mercedes procedure uses a special tool which does not allow the chain to skip while you are feeding the new chain through, i.e. the cams are rotating and valves are operating.

RWDlifer

I agree...without the valves operating, seems like the chain was skip-fed round a stationary crank...If the crank was rotated then the cams would have to rotate in time with the crank.

jpman

Correct. Pancakes did that while maintaining the crank pulley stationary. I did it this way considering that there was no resistance from the crank while rotating. it could have been that at the moment, in the position of the cams while doing so, were not interfering. Could it be that the valves and the pistons interfere only when the piston is at highest point, and valves at lowest point???

At the end of the day assuming no bent valve or scuffed pistons, as long as crank is at 0 deg and cam gears line up to their respective marks, timing should be dead on right?

krazzdav

That's where u already verified the crank and piston aren't matching up to TDC... thus the balancer has spun from it's original position. If u pull the bolt out you can tell 100% if the keyway doesn't line up close to 0.

RWDlifer

Correct. You should have something like this, and #1 piston at TDC. If your marks line up but the piston is not at TDC, then the crank pulley spun, as has been suggested.

https://mbworld.org/forums/c-class-w...hain-pics.html

jpman

if the crank pulley has spun, Should I replace? or should I just find tdc with piston at highest point and go on from there?

krazzdav

Replace it

jpman

It appears my timing marks were right, but maybe in the wrong cycle, this is the only thing I can assume. When I asked the mechanic, he simply states it was not in time. When I did it, the timing marks were dead on, it just wouldn't spin more than 90 degrees suggesting interference was happening.

He spun it in front of me and the lines all marked dead on. What happened is beyond me. I will update with pics soon to follow once she's fired up tomorrow.

krazzdav

that is strange because there's no way for it to be "180deg" out.

so what did the mechanic do different to get it to spin? did he redo the chain or was he able to spin it without doing anything?

In any case glad it's all sorted now!

ncmudbug

If I understand the situation, it is certainly possible for it to be 180 degrees off (whether it is likely is another matter). The degree wheel will show TDC twice for cylinder #1 for each complete cycle. Once just after #1 cylinder fires (since it will surely fire before TDC), and once as #1 is exhausting burnt gases. Of course when the cams are hooked up, both valves will be closed or nearly closed the first time and both valves are likely opened the second time.

I haven't read the procedure but it sounds like you - and the usual practice is to - do everything with cylinder #1 at TDC so you should line up the degree wheel on TDC and make sure that piston #1 is at TDC. That's probably when your cam marks need to be on their marks, too.

My guess is that somehow, you turned the crank 180 degrees.

krazzdav

but thats the thing....it can't be 180degrees off if you are just initially setting up the timing marks. If it was 180deg out then the cams will not be aligned to the mark.

The TDC mark on the balancer will be the same position for the pistons all the time. What causes it to be either on the exhaust or intake stroke is the position of the cams which with the marks lined up would be TDC on the compression stroke. For it to have been 180deg out then the cams would have been out of alignment.

With the chain connected one revolution of the crank will be 1/2 revolution of the cams. This was more critical on older engines with a distributor where it could be put in on the wrong stroke of the piston thus being 180degrees out. These engines with distributorless ignitions can't happen plus the marks for both the cam and crank were aligned so had to be at TDC...that's what doesn't make any sense.

ncmudbug

As I say, it's possible but I wasn't sure how likely it was - and to your point, I agree it does seem unlikely. To amplify your point, on some older non interference engines you might get even more lost. It would require somebody moving both the cams and the crank to get it as off as it was. I was merely going by the symptom.

It will be interesting to hear what the wrench did to get it to line up properly!

VVF

Guys, if you recall, jpman pulled the new chain through without moving the cams, so it is very possible that he might have rotated the crank an odd number of revolutions. Makes sense now.

I remember reading something like that, when people had the timing 180 degrees off, but didn't know that the pulley actually indicated TDC twice...

jpman

VVF this is what makes most sense to me. Is this even possible?

jpman

ncmudbug I'm not sure what was wrong, but I was truly dazzled when I showed up and he rotated the engine in front of me while the lines all aligned... without changing the crankshaft pulley. He also goes to note that these engines at the 0 degree TDC mark do not mark the top height of the piston. He mentions it has to do with the variable valve timing. He says it is close to 0 degree but not right on it.

jpman

Im glad it got sorted out as well. Let see how she runs tomorrow. I will start uploading pics and videos of her tomorrow guys.

jpman

So sometime today I will be picking her up, I will ask for more clarification on the issue to see what he think might have been going on. On another note, I'm a little scared if any damage was done to the valves by rotating the engine by hand and possibly interfering... The only time I felt resistance of interference was after installing the new chain as I tried to rotate the engine, it got to a point where it started to get hard and we immediately backed up and did not force it.

krazzdav

hey jpman can u ask your mechanic what he had to do to correct the problem? This will help others that come into this and we are all curious

---oops just saw your last post ^^^ I wouldn't worry about any damage though sounds like you stopped before anything would have happened

jpman

Sorry for the lack of updates guys. So went back today and they put everything back up. Cranked the engine, won't start . We kept on cranking and it just won't start, there are no metal noises at all, it just won't start.

He checked codes and none are being presented, checked fuel pressure and its good.

It seems as if its out of timing, it tries to start but it just won't catch. After much convincing he agreed to pull the crank pulley tomorrow and check the guide and the position of the marks of the pulley in relation to the guide on the pulley to check if it has slipped.

I am going to go on a limb here and we all probably knew on here that the problem was the pulley marks all along.

I don't believe any damage has been done in terms of interference, while it cranked it sounded very strong, no metal noises again, just normal starting noise of engine trying to catch but wouldn't.

We shall see where we fall tomorrow.

krazzdav

Bummer man.

Couple things.... You don't have to pull the crank pulley all the way off to see if it spun.... just pull the bolt out and see where the keyway is in relation to 0|T and U|T

Did you find out what he did different to correct the "out of time" that he mentioned the first time where you couldn't spin the engine but he could?

jpman

Yeah, sorry lack of sleep

Thats what I meant, he will pull the bolt and see the the relation to the marks.

According to him it was just that my timing marks were off. He specifies that the only way to do it is by locking the cam gears with the mb tool. Maybe he hasn't seen what people have been doing here? maybe once you do what I did which is basically set the timing as if it were a new engine you need to use that tool, Im not sure.

I mentioned to him that everyone on the forum that has done the job has specified that at 0 degree mark on pulley, 1st piston should be at the highest point. He mentioned that not always is the case on some engines, and he believed this was one of them, but after the no go today I assume he might be veering this way now since it won't start...