I have the cylinder head at the machine shop. Its from my 83 300sd.

The head is from another car because I had the camshaft and pedestals destroy themselves due to the vac pump bearing getting stuck in the timing chain.

Anyway, the head is at the machine shop and I want them to do a full rebuil.
I got them new seals and guides.

The thing I need to know is, the machine shop says Mercedes recommends putting in NEW valve and not to gring them. Is this true? What has everyone else done for a valve job. I told the machine shop owner, that I would get on the forums and find out.

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1983 300sd 150,000 miles on her (wifes)
1997 dodge ram 2500 cummins turbo diesel 550rwhp with a set of twins ready to go on.
2005 Audi A6 2.7T Sline Quattro
1998 30' Four Winds

The manual states that you can grind the valves if they meet the specs. If they are still in spec then have them reground , if not just buy new valves

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1986 300SDL, 211K,Dealership serviced its whole life
1991 190E 2.6(120k)
1983 300D(300k)
1977 300D(211k)

Any warning on the Vac Pump?

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

Any experienced machinist can measure the valve and see if it is too thin to grind.

Thanks thats what I was looking for.

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1983 300sd 150,000 miles on her (wifes)
1997 dodge ram 2500 cummins turbo diesel 550rwhp with a set of twins ready to go on.
2005 Audi A6 2.7T Sline Quattro
1998 30' Four Winds

Nope NONE! I rebuilt it about 1000 miles ago. It was just a weak piece that broke.

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1983 300sd 150,000 miles on her (wifes)
1997 dodge ram 2500 cummins turbo diesel 550rwhp with a set of twins ready to go on.
2005 Audi A6 2.7T Sline Quattro
1998 30' Four Winds

I was wanting to know. He said he could grind them, BUT since they are sodium filled he wanted to make sure, I was comfortable with it.

Anyways according to a couple of other guys these valves can only be ground once before you are starting to take to much metal away.

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1983 300sd 150,000 miles on her (wifes)
1997 dodge ram 2500 cummins turbo diesel 550rwhp with a set of twins ready to go on.
2005 Audi A6 2.7T Sline Quattro
1998 30' Four Winds

Only the stems should be sodium filled. You can grind the heads until they are out of spec. A machinist should be able to visually see if they are or not.

OK,
When you grind the face of the valve you also need to grind the stem so that the valve is the correct assembled length.

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1983 300sd 150,000 miles on her (wifes)
1997 dodge ram 2500 cummins turbo diesel 550rwhp with a set of twins ready to go on.
2005 Audi A6 2.7T Sline Quattro
1998 30' Four Winds

You fail to make mention of the diameter of the stem. This is what typically caused the valves to be replaced. If you ignore the diameter of the stem and insert new guides, the oil consumption will stay on the high side.

couldnt you just shim the spring and adjust the rocker? would you need to grind the stem?

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1982 300CD Turbo (Otis, "ups & downs") parts for sale
2003 TJ with Hemi (to go anywhere, quickly) sold
2001 Excursion Powerstroke (to go dependably)
1970 Mustang 428SCJ (to go fast)
1962 Corvette LS1 (to go in style)
2001 Schwinn Grape Krate 10spd (if all else fails)

There is no sodium filling in the Threaded ends of the Valves and only the Exhaust valves have the sodium filling.

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84 300D, 82 Volvo 244Gl Diesel

I have ground a god awful lot of Valves and you can not always tell by looking if the valve will have enought meat left on it until you have actually regound the valve face.

One V-16 Detroit Diesel with 4 valves per head has 64 exhaust valves in it.

I think the Mechanic is just trying to find a way to save his time=$. If he can talk you into buying new ones he will not lose money grinding some vlaves only to find out some valve faces may be too thin after they are ground.
If you are not supplying the parts he may be looking forward to taking a percentage on the parts sale.

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84 300D, 82 Volvo 244Gl Diesel

The mechanic may not have the skill to grind the valves. Unlike traditional valves, these have three faces that need attention. If the shop is not competent, you don't want them to touch the valves.

Doing these heads by folks that are unfamiliar with M/B is fraught with risk.

Thanks guys.
This machine shop has been around for along time and was recommended by another diesel shop.

I am going to find out tomorrow what he wants to grind the valves.
He actually wants me to replace them vs. grinding them.

Arizona ******** has intake and exhaust valves for $25 a piece. Anyone know if they can be had for cheaper?

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1983 300sd 150,000 miles on her (wifes)
1997 dodge ram 2500 cummins turbo diesel 550rwhp with a set of twins ready to go on.
2005 Audi A6 2.7T Sline Quattro
1998 30' Four Winds