Westfield Megabusa Build Diary

23 Jan 2008
Final engine preparation

We plan to install the engine this coming Saturday, but there are a couple of things that need doing before this can be done.

The drive pulley for the scavenge pump must be threadlocked and torque tightened, and the chain sprocket must be removed and replaced with a propshaft flange since the car does not use a chain.

The problem is, the chain sprocket just spins freely, so how can you take it off? You need to find the gear shift leaver and place it on the gearbox selector. It attaches on the splined shaft which is virtually next to the chain sprocket. Now get the car into gear, and it will couple the gearbox to the engine giving some resistance to push against. You have to remove a securing bolt with an Allen head socket. Now you need an impact wrench to shock the chain sprocket bolt off. With the bolt removed, the sprocket just pulls off.

Now you can put the output flange in its place and refit the securing bolt You need to threadlock it and torque tighten it, but you will find that the flange will begin to turn before you can get enough torque to the bolt (as it exceeds the engine resistance). You need to fit an M8 bolt through one of the holes in the flange and lever off it with a pry bar against the rotation of the flange and then you can tighten the bolt. Now refit the securing Allen head bolt.

You also need to threadlock the drive pulley bolt that you installed for the oil pump. This is done in an almost identical way, except for one small problem, I had the engine in 1st gear, so 10Nm of torque on the bolt gave about 30Nm on the output flange, so 50Nm was giving about 150Nm on the pry bar my Dad was holding. The solution is to put the engine in 6th gear where the gearbox gives hardly any torque multiplication. The bolt could be torqued easily now.

Engine preparation done - bring on Saturday!

(Didn't take any pictures - sorry!)