Valves - PeachParts Mercedes-Benz Forum

pj67coll · #1 10-11-2006, 11:44 AM

81 240D. It's been about 60K miles since my cars last valve adjustment. I've never attempted such a job before. Scared of getting into a hole I cant get out of. Can those familiar with the procedure give me an estimate of how long it would take a complete novice? If I have a whole weekend set aside what's the likelyhood I'll be able to finish it in that time?

- Peter.

gregszustak · #2 10-11-2006, 11:57 AM

Just did mine, first time - 81 240D easy

Hard to screw up unless you have a habit of losing small parts

Give yourself 4 to 6 hours which will include time to rest your back, ease off when you're aggravated and get coffee or food. If you get tired STOP

Read Diesel Giant (valve adjustment) 3 or 4 times and re-post after you've done this

riethoven · #3 10-11-2006, 12:05 PM

I am someone who is fairly mechanically inclined and it took me about 2 hours and that included cleaning everything as I went. Try to clean between the valve cover and the manifold before you take the valve cover off because it can fall onto the head once the valve cover is removed.

I bought the special wrenches and I am sure they made it much easier than using just straight wrenches, but the Haynes book shows using just straight wrenches. If you are in it for the long haul, invest in the wrenches. I was able to find them used on German eBay for 34 euros including freight to the US.

TchTchr · #4 10-11-2006, 12:50 PM

As I learned over the weekend, the Bottom nut is the lock nut, and the top nut is the adjusting nut.

OldPokey · #5 10-11-2006, 01:03 PM

Just did it myself - It was pretty simple. I took my time and used the wrench set from Diesel Giant.

pj67coll · #6 10-11-2006, 01:35 PM

I have the Haynes manual, and already have the special wrenches. Just trying to give myself courage enough to actually attempt the task. Is it necessary to replace the valve cover gasket when doing this? and are there any special torque settings for the valve cover bolts? As I dont have a torque wrench that could be a problem.

- Peter.

bgkast · #7 10-11-2006, 02:08 PM

I just finished my third valve adjustment on a MB Diesel and got it down to 45 min from cracking the valve cover nuts to tightening them back on.

It's not bad at all. 6 hours is a bit too much time to budget in my opinion...don't want to scare you off! If you don't have the "bent valve wrench" set I recommend removing the fuel injection lines to give yourself more room to work with the standard wrenches. Good luck

networkboy · #8 10-11-2006, 02:12 PM

Yes the gasket must be replaced.
As to the torque, there is a spec, but I'm not sure how tight the tolerance is...
Not near my shop manuals at the moment, but if no-one posts by the time I get home I'll add the specs to this post.
-nB

gregszustak · #9 10-11-2006, 02:17 PM

Quote:

Originally Posted by pj67coll

I have the Haynes manual, and already have the special wrenches. Just trying to give myself courage enough to actually attempt the task. Is it necessary to replace the valve cover gasket when doing this? and are there any special torque settings for the valve cover bolts? As I dont have a torque wrench that could be a problem.

- Peter.

Valve cover gasket would be a good idea, otherwise you may have to remove linkage and valve cover to install one.
Torque (??) No idea.
On a 240D it may be easier to remove the fan and crank CLOCKWISE from the crankshaft.

You need a small box for parts, box wrenches, sockets, pliers and a screwdriver.

Bunches of oil on the round linkage things before you try to remove and put back together

rrgrassi · #10 10-11-2006, 02:37 PM

If you do not have a torque wrench and do not plan on buying one, which even the needle/bar type is cheap enough, then you better be really good at feeling. If you can remember how much pressure you exerted removing the valve cover bolts, then that should be the pressure exerted to achieve the final tightening pressure.

Either way, too tight can split or displace the gasket, creating a leak, and too loose leaves gaps that cause leaks.

dannym · #11 10-11-2006, 02:50 PM

This is super easy so get out there and do it! Just make sure you have the proper tools.

A standard socket set and a 27mm socket to crank the engine aroung at the pulley.
2 14mm wrenches and feeler gauges.

The torque for the valve cover is 11 ft/lbs. which isn't much so if you don't have a torque wrench go easy.

It would also be a good idea to take a picture or 2 of the valve cover and all the linkeages. It may make it easier to put it all back together.

Danny

Stevo · #12 10-11-2006, 04:45 PM

It is NOT necessery to replace the gasket every time you do the valves, but I always do on a car I am doing for the first time, after that they last through several adjustings.

Too prevent leaks you need to wipe all the oil from both surfaces before reinstalling the valve cover.

If you want to make life eaieser just turn the engine (c/w) by the power streering nut.

I make a simple drawing so I can keep track of which valves I've done.

pj67coll · #13 10-11-2006, 05:35 PM

Folks. All this info is particularly helpfull so thank you all. I have a set of feeler gauges but need to get some other tools. Might need a week or so to accumulate all that but from reading the article on Dieselgiants site and seeing what you all have to say I'm almost looking forward to trying this. And I shall be taking pic's the entire way thru if only to document it for my own later amusement.

- Peter.

pj67coll · #14 10-12-2006, 03:32 PM

Question regarding this procedure. Diesel Giant's info shows the lobes pointing directly up at the 12 o'clock position. The Haynes manual clearly states and shows the lobe turned to the right. I guess in the 1 o'clock position. Which is right?

- Peter.

dannym · #15 10-12-2006, 03:57 PM

You can turn the lobe a full 180deg without moving the valve.
Technically it's straight up in relation to the rocker arm. But as long as you get it close you should be OK.

Look at picture #7 here:
http://www.peachparts.com/Wikka/OM617TimingChainStretch
I put that there for a reason.

Danny