First valve adjusmtent - PeachParts Mercedes-Benz Forum

stcbenz83 · #1 05-12-2006, 02:50 PM

I was reading some directions on how to adjust my valves, its says i need to let it sit over night? Is this true? or can i just wait a couple hours until it completley cools down?

thank you

stcbenz83 · #2 05-12-2006, 03:02 PM

Also what are the size wrenches for the valve nuts? i dont have the bent wrenches yet, so i was just going to pick some straight ones up, but i need to know the size of each of them

thanks

vstech · #3 05-12-2006, 03:14 PM

http://dieselgiant.com/valveadjustment.htm
awesome site for all things MB diesel!
John

stcbenz83 · #4 05-12-2006, 03:16 PM

that is a great link, and i have printed it off, but it dosent say the size of the wrenches i need to adjust the actual valves.

It says i have to let it cool over night. could i get away with it cooling for a couple hours?

MattBelliveau · #5 05-12-2006, 03:36 PM

The wrenches are 14mm, but as you can see from diesel giant's site, it is quite a challenge to get in these with straight wrenches (possible, but much more time consuming). I don't see why you couldn't just let it sit for a few hours and cool off. Good luck, and have fun.

vstech · #6 05-12-2006, 04:27 PM

is info for bending your own wrenches with a torch, basically get a good set of wrenches and grind down the open end thin enough to fit between the nuts, then heat red hot the wrenches and bend them to clear parts. but he says you gotta use good wrenches, the cheap ones just break.
John

Phil · #7 05-12-2006, 05:01 PM

Just do a search under valve adjusting wrenches, tons of stuff about them.
There are 3 wrenches all together. I made my own for under $10 for all three and they work great and have never shown signs of breaking.

Old300D · #8 05-12-2006, 05:14 PM

There is a plaque under my hood that gives valve clearances for temperatures under 30C or above 45C. Last Saturday was perfect weather, about 25C, so I adjusted the valves to 0.1mm intake and 0.35mm exhaust (I have a turbo). Strange how all 5 exhausts were tight and 3 intakes were tight. It's still counter-intuitve to me how they tighten instead of loosen.

stcbenz83 · #9 05-12-2006, 06:34 PM

there are 3 wrenches? i thought u only needed 2

1 for the lock nut, and the 2nd for the adjusting nut, whats the third 4?

and also a wrench to turn the engine

dannym · #10 05-12-2006, 09:22 PM

The third holds the spring keeper in case it turns on you. It very rarely does though. It only did it once to me and I just used a screwdriver to hold it in place ( old mechanics trick!).

Danny

Diesel Giant · #11 05-12-2006, 09:27 PM

Trying to do it with straight wrenches is nearly impossible on several of the valves. You should let the engine cool overnight if you can for best and most acurate results.

85chedeng300D · #12 05-12-2006, 09:49 PM

Quote:

Originally Posted by Old300D

There is a plaque under my hood that gives valve clearances for temperatures under 30C or above 45C. Last Saturday was perfect weather, about 25C, so I adjusted the valves to 0.1mm intake and 0.35mm exhaust (I have a turbo). Strange how all 5 exhausts were tight and 3 intakes were tight. It's still counter-intuitve to me how they tighten instead of loosen.

if i will make a guess, the first one who adjusted the valves before you, did it with the engine hot and then it cooled down before he's done. he probably adjusted those first three sets of valves while it is still hot then adjusted the last two sets of valves when the engine got cold already. notice the valve clearance on the plaque/sticker is 0.05mm thicker when hot than when it is cold or below 30 deg.C.

vstech · #13 05-12-2006, 11:33 PM

Quote:

Originally Posted by 85chedeng300D

if i will make a guess, the first one who adjusted the valves before you, did it with the engine hot and then it cooled down before he's done. he probably adjusted those first three sets of valves while it is still hot then adjusted the last two sets of valves when the engine got cold already. notice the valve clearance on the plaque/sticker is 0.05mm thicker when hot than when it is cold or below 30 deg.C.

and the spring pressure pulls valves closer to the fulcrum.
lowering the clearance.
also making the valves never closed properly and you lose compression.
John