Engine timing, valve train,  M110

Replacing valve stem seals

 

 

05—270 Replacing valve stem seals

 

Valve clearance
Cold engine (ca. 20 °C)
Warm engine (60 °C ± 15°C)

 

Intake
0.101
0.151

 

Exhaust
0.25
0.30

 

1) 0.05 mm more for consistent outside temperatures below —20 °C.

 

Tightening torques
Nm
Cylinder head cover bolts and capped nuts
5
Cylinder head bots M 12 x 1.5
100
Bolts M 8 for camshaft housing to cylinder head and crankcase
25
Necked-down screws for camshaft sprockets
80
Ball locating ring in chain tensioner
25
Special tools

 

 

Depressor for valve spring
m110 - 0172-1.jpg
110 589 04 61 00

 

Socket 27 mm, 1/2″ square for rotating engine
001 589 65 09 00

 

Impact extractor for bearing pin (basic unit)
m110 - 0172-2.jpg
116 589 20 33 00

 

m110 - 0172-3.jpg

 

Rail to hold down valve springs

m110 - 0172-4.jpg

»11004-7002
110 589 00 62 00

 

05.2-270/1 F3

 

 

 

Chain tensioner holder
m110 - 0173-1.jpg
110 589 02 31 00

 

Assembly mandrel for valve stem seals intake and exhaust 9 mm dia.
Installation mandrel for exhaust valve stem seals 11 mm dia.
m110 - 0173-2.jpg
116 589 00 43 00
116 589 01 43 00

 

Magnetic lifter for valve collets
m110 - 0173-3.jpg
116 589 06 63 00

 

Valve adjusting wrench 17 mm
m110 - 0173-4.jpg
110 589 01 01 00
11004-7003

 

Note
m110 - 0173-5.jpg
Remove camshaft housing with camshafts (01—470) and pertinent valve springs (05—250) to replace valve stem seals.
Valve stem seals are supplied in a repair kit with assembly sleeves.
The exhaust valve stem seal with 9 mm ID for engines starting April 1978 (emission-controlled engines start­ing model year 1980) has a holding bead inside (arrow) Do not mix up with intake valve stem seal without holding bead.
Valve guides, which are worn at the groove for the valve stem seal, must be replaced.
Valve stem seals
Repair set 123 586 03 05 (up to April 1978 or up to model year 1980 (@)).
Repair set 110 586 03 05 (starting April 1978 or starting model year 1980 (usa)).
m110 - 0173-6.jpg

 

Replacing
m110 - 0173-7.jpg
1 Press off valve stem seals.
Attention!
Don’t damage valve stem and valve guide.

 

05.2-270/2 F3

 

 

 

2   Deburr valve stem at groove (arrow).
3   Replace dented valve cones and spring retainers.
4   Check Rotocap and replace if necessary.
m110 - 0174-1.jpg

 

5 Lubricate valve stem seals and install with installa­tion mandrel.
Use assembly sleeve on intake valve.
m110 - 0174-2.jpg

 

6 Install valve springs (05—250) and camshaft hous­ing (01-470).
m110 - 0174-3.jpg

 

05.2-270/3 F3