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Re-fitting the Crankshaft Pulley to all variants of the 'A' series engine can often be a problem which can be classified into the following two distinct groups:
Problem 1
This is often caused by the Woodruff key, it's locating slot in the crank pulley, or the pulley bore becoming damaged or burred during removal of the pulley. This often happens when the crankshaft pulley is removed whilst the engine is in place as, due to the restricted space, a puller is impossible to fit and the pulley must be 'levered' off with a 'rocking' motion. In addition, if the pulley nut has become loose, due to incorrect locking, then the key groove in the pulley can become widened, and the bore damaged by the key as, with the engine running, the pulley works its way off the crank. Before refitting a pulley always check the pulley and crankshaft as follows:
The pulley should be a good fit to the crankshaft, but must be free enough to allow it to turn by hand to locate the keyway, and the key and keyway groove must both be undamaged, and free from burrs
Check the fit of the crank pulley on the shaft, ensuring it engages easily and rotates smoothly around the crankshaft, but has no free side play
If necessary, use fine abrasive paper or a small oilstone to remove any burrs from the crankshaft, the Woodruff key and from the internal bore of the pulley until the required fit is achieved
Carefully clean all mating surfaces using a rag soaked in a suitable solvent before lightly lubricating the shaft with engine oil
If the engine is removed from the car and is re-assembled to a point prior to fitting the timing sprockets to the crank and camshaft, the following additional procedure will ensure a good fit of the crankshaft pulley and also ease the fitting of the crankshaft timing gear and chain:
Remove the Woodruff key from its location in the crankshaft by gently tapping the front edge of the key upwards, using a screwdriver. This action will raise the front edge of the key from its radiused groove in the crank and, with further careful levering; the key will be removed from its location
Using a fine oilstone, carefully remove any burrs from the sides and front edge of the key, without reducing its thickness. Also, de burr the periphery of the keyway groove in the crankshaft
Before fitting the Woodruff key, trial fit the crank pulley to the crankshaft, as detailed previously
Refit the de-burred Woodruff key in position, but ensure that the front edge is angled down at the front of the crank. This allows the lower timing sprocket to engage easily with the key, which will then rotate longitudinally into its correct horizontal position as the sprocket wheel is pushed inwards into its final position on the crank. This same keyway is used to locate the crank pulley
Problem 2
Oil leaking from the around the pulley is most often due to the timing case cover being fitted and secured prior to fitting the pulley to the crank. (As detailed in the Haynes Book of Lies.) Due to tolerances in the fixing holes in the cover, this invariably means that the cover is not centered directly around the crankshaft, resulting in the pulley seal not being centered on the pulley. This allows oil to escape around the gap on one side of the seal whilst the opposite side is damaged due to it being pressed too hard against the pulley shaft.
Oil leaks may also occur due to the seal being damaged by sharp burrs on the pulley shaft as the pulley is fitted, or by the seal lips locating in a groove that the previous seal has worn in the crank pulley shaft.
Both these problems can be resolved by fitting the seal, timing case cover and crank pulley as follows:
Remove the old oil seal from the timing case cover, then ensure that its location is clean and free from burrs
Examine the new seal carefully for any damage to the inner sealing lips and ensure that the peripheral spring seal is in position (this is best done before removing the seal from its original packing, or when purchasing, as the quality of manufacture of these items is often poor)
Lightly grease the outer periphery of the seal, to aid fitting, then with the flat front surface of the cover firmly supported on a 'Workmate', or similar, and the protruding seal location positioned in a suitable gap between the jaws, carefully offer the seal into position. It can be a very tight fit and is best tapped into position by using the old seal, a front wheel bearing outer race, or suitable socket as a drift
If the pulley shows signs of wear from the previous seal then, when drifting in the new seal, leave it slightly proud of the inner face, thus presenting a new area of pulley shaft to the sealing lips
You can fit a suitably thin (2mm) gasket in position before the seal, but I have never found this to be necessary. The seal is such a good fit around its outer edge that it is oil tight even when left with a gap at its front face
Fit a new timing cover gasket to the engine block adapter plate, if the original is damaged or has been leaking, holding it temporarily in place with a very small amount of red 'Hermatite' or similar gasket sealer
Fit the Oil Thrower plate to the crankshaft nose, so that the letter 'F', stamped on the outside face, is visible
Apply standard chassis grease (Castrol LM or similar) between the pulley seal lips and then, very carefully, insert the pulley through the seal
Offer the complete assembly to the engine and, whilst supporting the cover, engage the pulley shaft on to the crankshaft nose. Whilst pushing the pulley gently inwards, rotate it until it engages with the keyway (using this method, the cover seal is always centered on the pulley shaft whilst the securing screws around its periphery are tightened)
Secure the timing cover, ensuring that the appropriate screws are fitted in their correct location. The 'short' screws fit in to the threaded holes found in the adapter plate only, whilst the longer screws pass through the plate and into the engine block
Fit a new 'tab' washer to the crank pulley securing bolt, fit the bolt then tighten to 75 lbf.ft. (102Nm.)
Bend the tabs on the washer to engage both the location in the crank pulley and an outer flat of the nut
Pete Kay (ERA Mini Turbo)
(28/04/03)
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