Valve adjustment issue - PeachParts Mercedes-Benz Forum

katchung · #1 10-07-2009, 06:57 PM

I finally got the nerve to do the valve adjustment on my beloved beast. It was going well...all of the valves were tight though...no space at all, so I'm psyched to see a potential difference in performance.

The problem is, that I hit a snag on the 5th valve. The spring is moving with the bottom nut, and I can't seem to get any space between the lobe and the top nut. How can I stop the spring from turning with the nut without getting a special tool? I tried wedging a flathead in the spring but it didn't work. Could I used a pair of needle-nose vice-grips to attach the plate at the top of the spring to the spring? Would that be enough to stop the spring from rotating with the nut?

Also, is there a way to turn the crankshaft from above?
Diesel giant suggests turning the engine by turning the power steering pump bolt. I tried this and the cyl camshaft lobes didn't move at all. I've been turning the engine over with the ignition, and it's hit or miss and really time consuming. How many rotations of the power steering pump bolt should I make before expecting the lobes to move?

Feeling a bit vulnerable with my baby's valve cover off, but excited about the prospect of hearing her purr like a kitten...

Thanks in advance for any suggestions.

funola · #2 10-07-2009, 07:06 PM

The vise grip on the spring should work. Try hooking a push button switch to the starter solenoid so you can blip the starter to turn the engine. This way you can see the cam lobes as they turn and adjust the ones that are pointing up.

Diesel911 · #3 10-07-2009, 07:11 PM

Here are the do-it-yourself links. Somewhere in there is a more detailed description of what to use to keep the upper spring seat from turning.
The 2 that I can remember are wedging the head of a 17mm wrench between the nearest bearing tower and the upper spring seat on one of the Hex flats so it will not turn and the other was inserting big Screwdriver between the Valve Spring Coils and the uppper seat to put more tension on it (I am otherwise not sure of the details on that).
I would think anything that would hold it with out causing damage would work (Channel Locks?).

http://www.peachparts.com/shopforum/forumdisplay.php?f=82

http://www.peachparts.com/Wikka/DoItYourSelf

Yak · #4 10-07-2009, 07:50 PM

Did my first valve adjustment a few weeks ago. Somewhere in the threads is the advice to use BOTH the alternator and PS pump bolts to rotate the crank. It's a bit awkward, but it wouldn't move on my car with just the PS pump. It turned pretty easy with both.

I got the full 3-piece wrench set on e-bay, so I can't help with the spring/nut issue.

Diesel911 · #5 10-07-2009, 08:15 PM

I used the Power Steering Nut/Bolt to rotate that Engine even though many Members say not. In order to use it you need to check your Power Steering Belt Tension.

If the Belt slips when you try to rotate the Engine try pushing down on the belt at the same time you turn the Pully Nut/Bolt.

After that, if turning the bolt will not rotate the Engine you need to loosen the Power Steering Pump and increase the Tension on the Power Steering Belt by screwing in or out the Belt Tensioner Screw.

When you are done you need to return the Belt to a more reasonable belt tension and of course tighten up the loosend Power Steering Pump.

The recommend place to turn the Engine is by the Crankshaft Bolt with a 27mm Socket (or 1-1/16 inch socket; same size as your Injector Removal Socket).
However, this is too inconvient for me.

snookwhaler · #6 10-07-2009, 08:18 PM

You have some good advice there....

I remember when I first adjusted mine. All but 2 were way too tight. The sound of the engine was much different after the adjustment. The engine was much smoother as well. I noticed no difference in power though and gained about 1.7 MPG afterwards running B20 (at that time).

I remember a couple of the nuts being a little tricky to tighten. Especailly towards the firewall. Having the proper wrenches finally made the difference.

Edit: I used the PS pump too with no ill effects. That was with new belts and proper tension.

tankowner · #7 10-07-2009, 08:22 PM

I used channel locks to gently hold the spring plate and that worked fine for me.

I wouldn't turn the cam shaft by wrenching on the power steering pump - that's just asking for trouble later. If you aren't going to do the 27 mm socket on the crank shaft then you will need to blip the ignition as you have been. I have read here of another alternative (I can't recall anymore who suggested this one). Jack up the rear, place it in gear, and then rotate the wheel CCW - as if driving forward. I have never tried it, but it sounds easy enough.

winmutt · #8 10-07-2009, 09:15 PM

19 mm wrench between nut and cam tower works like a champ.

charmalu · #9 10-08-2009, 12:47 AM

I use a 7/8 gear wrench on the power steering nut to turn the engine.

I was bumping the engine over using the terminal block by the battery. then the &%@$& engine started with the valve cover off

. I went from cool, calm, and collected

to panic Mode real fast.

I was grabbing rags to catch the oil from running down the sides of the engine.

Hold the stop lever back, or I guess a mity-Vac will work on the stop thingy at the Injection Pump.

Charlie

funola · #10 10-08-2009, 12:59 AM

Charlie, were you blipping the starter with the ignition key when the engine started? I would never take that chance. Muti glow plug cycles + fuel shutoff valve open can result in engine start.

Joe Marroso · #11 10-08-2009, 01:35 AM

Quote:

Originally Posted by katchung

I finally got the nerve to do the valve adjustment on my beloved beast. It was going well...all of the valves were tight though...no space at all, so I'm psyched to see a potential difference in performance.

The problem is, that I hit a snag on the 5th valve. The spring is moving with the bottom nut, and I can't seem to get any space between the lobe and the top nut. How can I stop the spring from turning with the nut without getting a special tool? I tried wedging a flathead in the spring but it didn't work. Could I used a pair of needle-nose vice-grips to attach the plate at the top of the spring to the spring? Would that be enough to stop the spring from rotating with the nut?

Also, is there a way to turn the crankshaft from above?
Diesel giant suggests turning the engine by turning the power steering pump bolt. I tried this and the cyl camshaft lobes didn't move at all. I've been turning the engine over with the ignition, and it's hit or miss and really time consuming. How many rotations of the power steering pump bolt should I make before expecting the lobes to move?

Feeling a bit vulnerable with my baby's valve cover off, but excited about the prospect of hearing her purr like a kitten...

Thanks in advance for any suggestions.

katchung

Here are my remembrances of my first 617 valve adjustment:

1) I used the power steering nut with additional pressure on the belt to achieve rotation. Putting a gigantic 27mm socket on the crank nut seems impossible because of the closeness of the radiator. I bought a long handle box wrench at Harbor Freight for this job. It was far from a perfect solution.

2) I hope I am in time to help. The spinning nut is easily rectified by getting the largest screwdriver in your toolbox. Place it vertically next to the cam bearing tower and let the shank of the screwdriver impede the CW turning of the hex nut. This is a clean solution and does no harm to the mechanisms. I am not going to discourage you from buying a third wrench from other enthusiasts. I assume they will work also. I am meticulous and the interposition of the screwdriver shank worked for me.

Good Luck,
Joe Marroso

Diesel911 · #12 10-08-2009, 11:15 AM

Quote:

Originally Posted by Joe Marroso

katchung

Here are my remembrances of my first 617 valve adjustment:

1) I used the power steering nut with additional pressure on the belt to achieve rotation. Putting a gigantic 27mm socket on the crank nut seems impossible because of the closeness of the radiator. I bought a long handle box wrench at Harbor Freight for this job. It was far from a perfect solution.

2) I hope I am in time to help. The spinning nut is easily rectified by getting the largest screwdriver in your toolbox. Place it vertically next to the cam bearing tower and let the shank of the screwdriver impede the CW turning of the hex nut. This is a clean solution and does no harm to the mechanisms. I am not going to discourage you from buying a third wrench from other enthusiasts. I assume they will work also. I am meticulous and the interposition of the screwdriver shank worked for me.

Good Luck,
Joe Marroso

You are in time as other people besides the Origional Poster will be reading this thread.

katchung · #13 10-08-2009, 11:40 AM

Thanks for all of your responses.

An update:

I finally managed to get the engine to turn using the power steering pump bolt. I've managed to do 4 of the five valves no problem. The 5th valve is hard for three reasons.

1. There is very little space to turn the wrench because the firewall is right there.

2. The spring and plate are spinning with the bottom hex nut, and hence nothing is happening...I"m about to go out and get a channel lock to hold the plate in place. I tried to use a 19mm wrench wedged between the cam tower and the spring plate, but this didn't work for me. Jamming a screwdriver in didn't help either, because I just don't seem to get the correct angle to stop the spring and plate from moving. I'm concerned about doing damage this way as well.

3. The bottom nut is misshaped, and the 14mm wrench won't go over one of the hex angles easily. I have been tapping it with a hammer to get it to fit. I think I would be best served to just replace this nut, but I admit, due to the unknown, I'm afraid to start taking the valves apart to remove the bad nut. It still seems to rotate ok on the stem, so I assume it's not stripped...it will also lock with the top nut, which is another good sign.

As a side, I've noticed some funky gunk on the inside of the valve cover. There is an almost tan looking hard substance in certain places. When I say hard, I mean impenetrable and plastic-like. Looks almost liked something was patched, or like epoxy was spilled. I'm wondering why it is there, and for what purpose, and whether or not I should try to chip it out. Also, there is some congealed oil and grime that I'm sure shouldn't be there. What should I use to clean it out?

As always, this forum kicks a$$. I'm amazed at the generosity of its members, and deeply grateful for the patience that people have for noobs.

I look forward to giving back as I learn more.

Thanks!