Head removal sanity check (M110)
 

So I very likely have loose valve guides and will need to take the head of my 280slc to a machine shop. Before I do so, I just want to make sure I understood a few things that are not very clear on the service manual:
-The timing chain does not need to be opened to remove the head, right?;
-The head does not use stretch bolts (so they can be reused?);
-The manual mentions a special tool (116589010100) to hold the camshafts. Are there any alternatives to this tool?

By the way: are there any While I'm In There™ type jobs that could be done since I'll be taking the head off?

Thanks.

Should the chosen shop advise you of a "warping" condition, stop.

Any surface machining with the objective of restoring "flatness" must be thought through very carefully. If the bottom surface (the head gasket side) is "warped", so too is the top side (the cam box side). If the bottom were to be machined flat, and the top left "warped", when the cam box is subsequently bolted to the "warped" top surface, the cam box will be itself "warped", and the cams will not turn in their bearing bores!
If there is no corrosion on the head gasket surface that would warrant machining, leave it alone. When re-bolted to the block, the head will become flat again.

Thanks Frank Reiner.

I'll see if I can post some pictures of the process when I get to it.

That tool for the cam shaft is basically folk made of soft enough metal that it will hold the cam shaft, but without marring it. You can get the same result with a largish allen wrench and a cloth wrapped around the cam shaft's rougher surfaces (not the cam lobe).

The hard part for me was always the timing chain tensioner. It's tedious.

Also, regarding the bolts. There is a spec for how thick they should be (stretched == narrower). Not that I have it handy. If the bolts are necked down due to stretch, replace them. They probably won't be.

-CTH

allen wrench? "allen" wrenches are for internal wrenching fasteners; perhaps a pipe wrench is what was in mind.

A spec for M110 head bolt stretch will not be handy...for anyone. It does not exist; they are not stretched to the point of yield. (see the second post, above)

If it's because of the AC compressor that you have to remove to get to it then I understand. I've been in houses that were less supported than that compressor unit!
Spent the hole day today fighting it before I realized that the radiator has to come out first to get to a hidden bolt under the compressor. Ugh.

As long as you are there, and as Frank mentions - no warping, carefully check the oil pressure chain tensioner. They sometimes get so gunked up that they need to be replaced. Definitely change the upper rail guide tensioner. Neither of the aforementioned parts are expensive by MB standards. If you are concerned about the head bolts, they can be had for between $2 and $3 each (non stretch).

You know what? That actually worked really well. I present you all the "Official Mercedes Camshaft Locking Tool™" (see attached picture).
Available now for only US$ 499.99!

Now on to a more serious issue: does anyone know of a valve spring compressor that fits on an M110 (and doesn't cost an arm and a leg)?

camshaft housing is separate from the cylinder head so once you get it off you should have plenty of space to get to the valve springs with any spring compressor

I could do that, but it would mean opening the chain, which I don't want to do. Despite the looks this is a low mileage engine and the chain is still very tight on the sprocket.
To free the chain first I must push the cams back, and to do that first I need to remove the rockers which requires the compressor.

Here's a cheapo that just might do the job, perhaps with a bit of customizing:

https://www.ebay.com/itm/Valve-Spring-Compressor-Lever-Type-OHV-OHC-Engine-Seal-Keeper-Removal-Tool-Kit/233005003334?fits=Make%3AMercedes-Benz&epid=27025855898&_trkparms=ispr%3D1&hash=item36402e3246:g:7c8AAOSwLKhb68ok&enc=AQAEAAAB8BPxNw%2 BVj6nta7CKEs3N0qUkU51pdX81mect%2FPKmj31s7G18M0tFy5DBNaSZExnpagQMFfkPWwaiLH5DgJdiV2ee7vgwlwZafvNa76yt 9GKipFh1ZfJK0tqLuX9gySfH3Jmc1SQF21S5k8ntzM2Jc7X2F3Qp3peA7LlOEC2IPUl4Y3Dds2%2B9zb3Ta64tfad6vg8nv8VkjH EKvdkePXb79eFGp4DS1j460Vou6%2B1bd%2BBNKiKaHTCyLANIVOe9U6Eq7mXJHeshdtJzH5MXP9Fwaxf7zhwzx6tzbTAr5tZY9s oZVN2jr703Ejd%2BqaT8wscre6lkg3TPzYw07qkvQ%2Fs31eitrIr8NVta3sMCEQkjeQhw8iVDMH31ezi77Fa4lIKjpk61ENLfLG 1bmy2TFlBI%2FOEs8C3KeAWL41slH9GynFt5rfRyaQU9PpR1iseLQUxazu0BcG1awM4kLFH%2FfAmPHMJMhmJpTUGoldiKGxBh%2 FS5QyQnh4rcPtGXk8zhXGqBjxCWBtchAEmCVQ6O6GLFWC1lvjxb747AhceKA7veSPlfRrC18qO56vfpgOuRk5eAHKiAlKAVIDRmv LwrpoyNpQvb0p8xt2%2B27l15bJtf05F63kdRi65X0W11WnqFZBtXWm6OKgoG9z1g11Wc3peTqsSY%3D&checksum=2330050033 34beb8517bca1a4818b89dd08a647ed16e

Thanks. I might try that one.

Hello guys! I have to get the head out of my w116. Do you have any updates on this discussion? The timing chain does not need to be opened to remove the head? Thanks in advance!