Removal
1. Remove the camshaft timing chain cover as described in paragraph 6.
2. On a carburetor engine, remove the fuel pump as described in Chapter 4A.
3. Remove the camshaft sprocket as described in paragraph 8.
4. Using quick-drying paint or a scraper, make marks on the camshaft sprocket and on the corresponding link of the drive chain.
5. On single chain models, pull off the lower guide rail.
6. If necessary, rotate the auxiliary shaft so that the shaft lock bolt is visible through the holes in the sprocket.
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7. Working through the hole in the sprocket, loosen the retainer bolt, then remove the auxiliary shaft retainer (see Fig. 9.7, a, b).
Fig. 9.7, a. Loosen the auxiliary shaft retainer bolt...
Fig. 9.7, b... and remove the retainer
8. Separate the drive chain from the sprocket, then remove the auxiliary shaft from the cylinder block (see fig. 9.8).
Fig. 9.8. Removing the auxiliary shaft
Examination
9. Check for wear or damage to the shaft surfaces (especially on the driving surfaces of the fuel pump and distributor). If defects are found, replace the shaft.
10 Check the wear on the sprocket teeth. Each tooth forms a reverse "V". If they are worn, the stress side of each tooth will be slightly concave when compared to the other side of the tooth (i.e. the teeth will look like a hook). If the teeth are worn, the sprocket should be replaced.
Installation
11. Insert the shaft into place in the cylinder block, then install the retainer and tighten the retainer bolt to the required torque.
12. Place the chain on the auxiliary shaft sprocket.
13. Where provided, install the lower guide rail.
14. Make sure that the marks on the chain and crankshaft sprocket are aligned before removal. Install the camshaft sprocket as described in paragraph 8.
15. On carburetor models, install the fuel pump as described in Chapter 4A.
16. Install the camshaft timing chain cover as described in paragraph 6.