Engine timing, valves,  OM617

Checking and machining valves



05—280 Checking and machining valves


Intake valve
Exhaust valve
Valve retainer dia.
Valve stem dia.


Valve length


Code number on stem end
E 617 00
A 617 00 27
Filled-in sodium
Valve seat plating
valve seat nitride-hardened



when new


Height “h” of valve retainer


limit value


Adjusting angle for machining valves
30 + 15′


Permissible runout at valve stem and valve seat max.


Valve shaft wear (wear limit)


Conventional tools


Valve cone grinder
valve cone machining tool
e.g. made by Matra-Werke GmbH
D-6000 Frankfurt/Main 8
e.g. made by Hunger, D-8000 Miinchen




Exhaust valves are filled with sodium.
When scrapping valves, pay attention to safety rules. Do not melt valves filled with sodium, since there is a risk of explosion, and do not use such valves for making tools (punch, etc.), without first removing filled-in sodium.


05.8-280/1 F 2




Be careful when removing sodium from valve, since sodium mixed with water and watery solutions reacts heavily explosive, while the resulting hydrogen gas may cause fires.
Sodium from cut-up or broken-up valves can be neu­tralized in a mixture comprising 2 liters of spirit of alcohol and 1 liter of water put into a vessel and placed in the open air.
Valves filled with sodium can be collected and ship­ped for neutralizing to: Garantieprtifstelle Werk Stuttgart-Unterturkheim.


Checking and machining
om617 - 0183-1.jpg
1 Clean valves and check visually.
Valves with a burnt valve retainer, with insufficient height “h” of valve retainer and valves with worn out or scored valve stem should be replaced.


2 Measure runout on valve stem. If runout exceeds 0.03 mm, replace valve.
om617 - 0183-2.jpg


3   Machine valve seat.
Refer to operating instructions of machining tool and make sure of a 30° adjusting angle.
4   Measure runout on valve seat and height “h” of valve retainer.
As soon as the limit values are attained, replace valve.
om617 - 0183-3.jpg