Wrench for adjusting valves? - PeachParts Mercedes-Benz Forum

The Warden · #1 05-29-2002, 01:15 PM

Okay, I've heard a few people talking about taking a 14mm wrench and bending it so they can adjust their valves.

Please keep in mind that I haven't taken a look at the valvetrain on the 5 cyl diesel, but I'm having trouble picturing why this would be necessary. I've adjusted the valves on my old '74 VW Bug, and I checked the valves on my old '80 IH Scout (they were all within spec), but I haven't dealt with adjusting the valves on an overhead cam engine.

So, why is the "special" wrench necessary? Or is it just to make life easier? Can it be done with "normal" tools? I don't have access to a torch, so bending a wrench by myself isn't much of an option (short of a vise and a BFH)...does this mean I'd have to go out and buy a special tool?

Just wanting to know...thanks!

JimSmith · #2 05-29-2002, 01:30 PM

The Warden,

I would put the special wrench in the category of mostly nice to have. It is an offset handle, right near the wrench section, and a thinner wrench section than is normally supplied with a Craftsman or other typical 14mm wrench. I have never tried with anything else, as I bought the wrenches back in 1975 or so. Still have them and have adjusted the valves dozens of times. I think they are worth the cost, which should be around $30 to $40 bucks. That gets you two identical offset handle 14mm wrenches and a special wrench I will not try to describe that is used to hold the valve spring retainer and valve and keep it from turning while you tighten and loosen the adjusting nuts. You will need some kind of offset handle and a thinner wrench or you will likely round the corners of the nuts off over time. Good luck, Jim

leathermang · #3 05-29-2002, 01:43 PM

Bill, you silly rabbit ! You were using them backwards..... don't dis my cheap homemade bent wrenches. I mentioned that you had them wrong one up but you were so engrossed in the process that you ignored me....

Not only do mine " nest " but they have room for your fingers to move between them.. and they have round hand holds that are not sharp on the edge like most wrenches....

#4 05-29-2002, 02:23 PM

I did a little search and found an excellent picture of the wrenches HERE

Man those are sweet looking tools.
It's not that hard to make your own and if you bought a very thin 14mm which is optimal anyways, you wouldn't need to use heat to bend it, just put it in a vice and reef on it.

I only made one bend in mine and it worked fine.

good luck

jim

leathermang · #5 05-29-2002, 03:25 PM

JimSmith, it is a small point, but might be helpful for those bending their own to note that they are not " identical " bent wrenches... otherwise they will not nest... the bend in the top one has to start a shorter distance from the wrench opening in order not to interfere with the lower thin wrench...

Greg

The Warden · #6 05-29-2002, 05:20 PM

I see now...thanks for the pic! That really helped with visualizing the wrench design...

wheelguru · #7 05-29-2002, 05:42 PM

I just adjusted my valves for the first time a couple weeks ago and some of them were way off. I had no idea how far to screw the retaining nut til I hit upon the idea of leaving the feeler gauge in place and then turning the nut until the valve came up to the gauge. At least then I knew I was close and could fine tune from that point.
I did not know about turning the valves to find the high point and working from there - makes a lot of sense. I will do it next time.
I recommend the special wrenches, they were easy to use and the retaining wrench was necesary. I attempted it once without and got some of them done but could not do all the valves as some turned when I tried to move the adjusting nut.
At some point this summer I plan to tackle checking the stretch on the timing chain. Should I take photos? -Andy

JimSmith · #8 05-29-2002, 05:49 PM

Greg,

Once again, you are correct. There is about .5 cm difference in the location of the knuckle in the handle, one being about 3.5 cm from the center of the knuckle to the end of the wrench and the other about 4 cm. The design of the wrenches, open end ones, allows quite a bit of manuevering room for the wrenches, and I have never really paid attention to the order in which I use them. I will from now on though. Jim

leathermang · #9 05-29-2002, 10:26 PM

Can rotators be placed on the intake valves ? I know of some engines which have them on both...

JimSmith · #10 05-29-2002, 10:49 PM

Greg,

My manual does not explicitly say they both have them, but in the instructions for replacing the valve springs it makes no distinction for the procedure on intake and exhaust valves. The instructions say "Insert the valve spring with the mark "unten" (bottom) toward cylinderhead (rotocap)." There are a number of cross section views of the valve, guide, rotocap, spring, spring retainer, cap nut and lock nut, and stem seal. None are labelled intake or exhaust, and all show the rotocap. I would conclude both valves have rotocaps based on this, but as you have demonstrated, I can be off target now and then. Must be aging.

Jim

sainttammany · #11 05-29-2002, 11:32 PM

I bought a handfull of 14 mm open ends at the pawn shop for a buck each. I have adjusted the valves about 15 times without any problems. Most pawn shops have a large inventory of tools, at low prices.