V8 engine build part 2 – (more) new main bearings, crank and piston fitting

V8 engine build part 2 – (more) new main bearings, crank and piston fitting

New year, new… main bearing shells. The genuine Land Rover bearings arrived, so I didn’t waste any time in finding out if they solved my problem with the crankshaft clearance. A visual comparison with the aftermarket ones didn’t show any difference in thickness of the thrust faces, so I wasn’t overly confident, but the tolerances are pretty tiny so it was worth a try!

Aftermarket upper bearings out, genuine ones in, and… the crankshaft dropped straight in and span freely – success! I quickly fitted no. 1-4 bearing caps and set them to the initial torque as per the overhaul manual.

For the rear bearing cap, the manual specifies a bead of Hylomar jointing compound, so that’s what it got. I then refitted it with new genuine “cruciform” side seals. Since this is a 4.6 block, all of the bearing caps are also cross-bolted, so those bolts went in next with brand new dowty washers to seal them, and then I did the final torque down of all the bolts in the correct sequence.

With the crankshaft buttoned down and still rotating freely, I moved straight onto fitting the pistons and big-end bearings. Since I’d already cleaned the pistons and pre-fitted the new rings, this didn’t take very long at all. The pistons are all clearly marked with an arrow pointing to the front of the engine, and a distinctive dimple on the con-rod to indicate fitting direction, so it would probably be pretty difficult to mess this up. A decent piston ring compressor and plenty of engine oil on the rings and around the bore made quick work of it.

Working in pairs as I put the pistons in, I fitted new big-end bearing shells, and torqued them down in 2 stages to specification. And this just about gets me back to where I was before I decided to mess with the crankshaft in the first place – hooray!

Whilst I was here it was another good chance to liberate some more parts from storage, so I dug out the original oil pickup assembly and windage tray that I had bought with my SD1 sump and cleaned them up for fitting. Here they are with a new gasket for the pickup pipe, new sump gasket, oil drain plug washer, and a new set of stainless sump bolts. Rimmers SD1 parts catalogue helpfully includes a very useful diagram of how all these pieces fit together, which I printed out for reference.

The bracket that will support the oil strainer bolts onto this stud, which screws into a hole on the no.4 main bearing cap. It was super helpful of Land Rover to make sure the late engine castings were still compatible with these superseded older parts like this!

The windage tray then locates over the stud and is attached to the block with 6 bolts, before the pick-up pipe and strainer can then be bolted on themselves.

I didn’t properly fit the sump at this point since it will need to come off again when I fit the timing cover, but I’ve loosely secured it in place with a couple of bolts for now to help keep things clean until I get to it.

Really pleased with the fast progress on this, and a good lesson learned on the occasional false economy of aftermarket parts. I did finally start work on the rear wheel arch replacement in the midst of all this, I will focus on that and get it finished before any more engine work, so look out for an update on that shortly. Hopefully I’ll have all the remaining engine parts in hand by then too, so there will be lots more to come on this.

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