Hi Everyone - Got a question in regard to my E300 I'm kind of stuck on, (same engine used in the W205 M274, so i thought i'd ask here as well). I am unsure if anyone on here can assist or if anyone has done this before:
I am planning on replacing the timing chain, chain tensioner, camshaft adjusters, and camshafts on my M274. It has the infamous rattle on startup and was looking to do the job my self seeing it's pretty straight forward with the right tools. I just cannot find the answer anywhere as to whether or not when replacing the timing chain can I leave the camshaft lock down tool on the camshaft and then rotate the crank to pull the new chain in or do I have to completely remove the camshaft and then rotate the crank?
In the MB service manual the pictures show that there is no camshafts and no camshaft tool when snaking the new chain in.
Only reason I am asking if the chain can be replaced without removing the camshafts is because: 1) I do not want to mess with the timing/position of the camshafts too much, and 2) I've seen a couple of videos on YouTube snaking the chain through on M270/M271/etc engines that are all "Interference" engines and should not able to do such a thing.
Bumping this up again. Any one have any insight on this? Do the camshafts have to be removed in order to snake in the new chain when rotating the crank?
I have seen many timing change videos and they all require the engine to be removed. For this one it looks like MB has a way to do it without such and issue. From what I have read, you need to connect the new timing chain to the old and pull it or snake in the same direction that it moves and then once the new change is through and back out, you reconnect it the new assembly link.
Let me add that you will also need to make sure there is tension on the chain at all times as you turn the engine.
Let me also add again, you will need to make sure you have already locked the cam, marked the change and cams before you remove the cam sprockets to gain access to a loose chain.
I have seen many timing change videos and they all require the engine to be removed. For this one it looks like MB has a way to do it without such and issue. From what I have read, you need to connect the new timing chain to the old and pull it or snake in the same direction that it moves and then once the new change is through and back out, you reconnect it the new assembly link.
Let me add that you will also need to make sure there is tension on the chain at all times as you turn the engine.
Let me also add again, you will need to make sure you have already locked the cam, marked the change and cams before you remove the cam sprockets to gain access to a loose chain.
Correct on all those points. I already know that part. I was asking if I can turn the engine/crank while the camshafts are locked in at TDC with the cam adjusters removed? I am afraid that if the cams are locked into place with the tool that spinning the crank while pulling in the new chain will cause the valves to hit the pistons or vice versa.
I see no other way of pulling the new chain until unless I remove both camshafts along with the camshaft adjusters which I do not want to do. I'd rather just take off the camshaft adjusters and leave the camshafts locked into place with the TDC hold down tool.
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