Checking and machining valves

when new

2.54

2.49

Height “h” of valve retainer

limit value

2.0

2.0

Adjusting angle for machining valves

30 + 15′

Permissible runout at valve stem and valve seat max.

0.03

Valve shaft wear (wear limit)

0.05

Valve cone grinder

or

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.

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.

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.

05.8-280/2