21 August 2016
Motor take two.
The balancer puller arrived on Wednesday and on Friday I whipped the balancer off. Pretty straightforward and will clean up well. A friend was telling me that Wagga hosts one of Australia’s leading harmonic balancer manufacturers, Precision Parts the makers of Powerbond. Their product is apparently world class- there you go.
The PO mentioned the engine had a sticky lifter and so I was keen to check this out. Loosened off the rockers and removed the push rods. I had pre-drilled a series of holes in a block of timber so I could keep the rods in their original spots. The inlet for No 6 piston was different to the others. This one had no ball on the ends, was slightly shorter and I suspect was the reason this cylinder was not running correctly.
With the push rods out I could use the magnet to remove the lifters. All came out really well and look to be in great nick; no overly concave bases or signs of wear.
With the balancer off and lifters out, I could remove the timing cover. Hold on, remember I was saying the PO used 12 point ARP fasteners, well he used them on the timing cover but I only have a single hex/6 pint ¼ socket. Fortunately, only one bolt was a little tricky but I got that off. Had to remove the sump to get the cover off.
With the sump off, I could see the PO did a bit of ‘tweaking’. The two humped sump has a baffle swing ‘gate’ dividing the two ends of the sump. In effect, the gate stops oil moving away from the oil pick up under heavy acceleration. When the car settles, the oil returning to the rear hump builds up and pushes the gate open, thus allowing it to flow into the larger hump awaiting for pick-up; effectively a gated baffle.
The other thing he appears to have done is used a shit load of assembly lube OR the bearings have completely disintegrated and are now sitting as very fine mud in the bottom of the sump. I am hoping for option 1. Scraped the mud away with the oil (what had not covered my floor).
Sump off and timing cover removed to reveal…a double row timing chain. Love that!
But, the top sprocket was attached with three 5/16 12 point bolts. You guessed, it, my 5/16 sockets are all single hex and I was left to use my baby ring spanner. Leveraged on that little guy and they came free. PO had used Loctite to secure these in; like he should have. I did some searching and it appears to be a Comp Cams set with a Rolon chain. Photos taken to ensure correct reassembly. Just on that, you might notice the bottom sprocket has three key-way locations. Research has revealed these allow for TDC, 4deg advance or 4 deg retarded. Mine was on TDC. If you zoom in on the image below you can see the A and R adjacent to the other keyways.
Carefully slid the cam out of its home in the valley. Everything looks nice and even across the lobes with no signs of wear. Confirmed by my cam consultant, JBB. Unfortunately, there were no signs of part number or manufacturer either.
With the cam out, I was in a position to inspect bores and overall condition.
Compression was clearly still good (read springs are seating the valves well) as I was having trouble turning it over. Hold on, take the plugs out you goose to lose the compression. With the plugs out, the crank spun freely. Rotated it so that I could inspect each bore with the torch. They look good with some of the honing marks still visible. Pistons are alloy, consistent with the PO saying they were forged. The brand was not clear but the logo is a triangle with a what looks like a T inside it. Now identified as a DnB piston
Oil pump is a Melling high volume unit. The whole rotating assembly feels solid with no slop, play or odd movement/notchiness.
Went to Total Tools and picked up a ¼ and 5/16 12 point sockets; got the quarter in a deep ¼ drive as well.
Back home and it was bench grinder cleaning time. Cleaned up the inlet, timing gear and cover bolts together with the cross member bolts and rear quarter window ball studs.
Cleaned out the sump with kero and will strip this ready for reassembly with new gaskets etc. back on the motor. Still undecided on what to do for induction.
