Sep 12, 2012

Fitting the camshaft, timing gear, distributor and oil pump

Fitting the camshaft is a very simple matter but you need to be very careful not damage the bearings with the sharp camshaft edges when sliding it in the block. So you need a steady hand, a beer and no coffee :)
There are several camshaft types, the engine I bought came with a sporty Type K camshaft in the box. When fitting a new camshaft, always use new cam followers (with a flat bottom) otherwise your cam will be gone in notime.

After fitting the K-camshaft I put on the flange with new bolts that came with the original timing gear kit. When I had a look at the exploded view in several part catalogues I saw some kind of washers being used between the bolts and flange. I assume the new bolts are self securing ones so I fitted the flange without the mysterious washers. After that I pushed in the woodruf key and hit it gently with a hammer.

Genuine Volvo 122S Timing gear set
Genuine Volvo 122S Timing gear set

Fitting the camshaft flange Volvo 122S B20B
Fitting the camshaft flange Volvo 122S B20B
You can't just hammer the new gear on the camshaft; it's made of fibre and will break. With a bit of oil on the cam it was possible to push the fibre gear on far enough to put on the big bolt. It such a big bolt (36 mm) that I didn't have the right size socket in my toolbox. But after spending 22,50 dollar I could finally thighten the bolt to 145 Nm. To prevent the gear from turning while thightening the bolt I put a high tensile bolt in one of the holes of the gear.
Thightening the 36 mm K camshaft bolt Volvo 122S
Thightening the 36 mm camshaft bolt to 145 Nm
Before fitting the steel gear you have to turn the crankshaft in the correct position. The marks on the steel gear and fibre gear have to line up (see picture below).
The little steel gear was a bit harder to push on the crankshaft, actually it was impossible. Somebody told me to heat the gear and sleeve so they would expand a bit. I put the gear and sleeve for 30 minutes in a 220C oven and, while still hot, I could easily slide them over the crankshaft. For the last mm's I tapped the sleeve with a rubber hammer.  Btw I didn't know that garden gloves could produce smoke...

New timing gear fitted Volvo 122S B20B
New timing gear fitted Volvo 122S B20B
With the gear in this position I put in the distributor drive gear ; Cylinder 4 (the one at the back of the engine) is now in TDC and the distributor rotor should point at plug no. four. Or you can turn the shafts so that Cylinder 1 is in TDC and the rotor selects plug number one (the rotor turns CCW and the crankshaft CW). Just an extra check: If you take a closer look at the drive gear you'll see that there is a small -and a big part at the groove on top. With Cylinder 1 in TDC put the gear in at an angle of 35 degrees. When you place the distributor on top of it, the rotor should select plug number one (see pics below). 

Drive gear at an angle of 35 degrees with cylinder 1 in TDC
Drive gear at an angle of 35 degrees with cylinder 1 in TDC

Rotor selecting plug number 1 with cylinder 1 in TDC - Timing gear Volvo B20B
Rotor selecting plug number 1 with cylinder 1 in TDC
See numbers corresponding with cylinder numbers

Bosch Distributor 0 231 146 078  JFUR4 1969 Volvo122S B20B
Bosch Distributor 0 231 146 078  JFUR4 1969 Volvo122S B20B

The distributor looks ok, so I only replaced the cover, rotor, points and leads. There's a cup on the side of the distributor (close to no 1 on the pic) in which I put oil for the lubrication of the shaft. To lubricate the advance system just put 2 or 3 drops of oil on the felt top of the shaft. After the distributor was bolted on I turned the engine on the stand and fitted the oil pump and pipe with new rubber rings. I had to buy a new pump because the tooth flank clearance was to big which will cause a lower oil pressure.

Old oil pump Volvo 122S B20B
Old oil pump Volvo 122S B20B

New oil pump installed Volvo 122S B20B
New oil pump fitted in the B20B

New oil pump installed Volvo 122S B20B
New oil pump and distributor