Note
The following engines are provided with a thermostat in oil filter:
Engine 615 in model 123.1 on vehicles with air conditioning system.
Engine 616 in model 123.1 up to August 1978 generally and starting August 1978 on vehicles with air
conditioning system only.
Engine 617 in models 115.1 and 123.1 generally.
Remove functioning thermostat only at temperatures below 60ยฐc, since otherwise the thrust pin (a) willbe pushed out.
Never pull thrust pin (a) out of wax thermostat, since otherwise proper function will not be guaranteed any longer.
A. Engine 61 7 in model 1 15.1
Removal
1. Unscrew closing plug (arrow).
2. Remove thermostat with control valve and compression spring.
Installation
3. Insert thermostat with control valve and compression spring.
4. Screw-in closing plug with new sealing ring
5. Check oil level
B. Engine 615, 616, 617 in model 123.1
Removal
1. Remove oil filter (18-110).
2. Unscrew valve seat ring ( 17) with wrench socket.
3. Remove start valve (16), spring retainer (13) and compression spring ( 15).
4. Remove thermostat ( 11) with control valve (12) and compression spring (10).
Installation
5. lnsert thermostat (11) with control valve (12) and compression spring (10).
6. Insert spring retainer ( 13), compression spring (15) and star valve ( 16).
7. Position valve seat ring and tighten to 40 Nm (4 kpm) with wrench.
8. Peen valve seat ring in both recesses on oil filter housing (arrows) by means of a crosscut chisel.
9. Install oil filter with new gasket.
10. Correct oil level.