Thread: Disco 1 3.9 V8 motor. Rebuild or not?

Number 7 & 8 lower head bolts can be a real PITA.
I found using a single hex impact socket with a uni joint 2 500mm long extension bars fed in the most direct rout as possible to the head bolt and then a 1metre long breaker bar and work out side the engine bay. And Wait for the big bang as the bolt lets it's grip go. They go off like a shotgun blast.
They are also a pain to torque up also due to access.

OK, I have some progress. I've pulled the motor and dismantled it. In the end I got the last head bolt off with a 5/8ths impact socket and a 600m breaker. The sleeves all look intact, no signs of slippage. The only real concern is the cam, which seems to have a very worn lobe. The follower/lifter for that lobe also has a matching concave surface. So...new cam and lifters. As with everything else I think I'll go for the standard items, not to expensive and likely to provide an adequate level of reliability (please let me know if I'm way off here).
The timing chain and gears look OK, but I might replace them too. The crank also seems to be in pretty good shape, though I haven't taken the micrometer to it yet. End float is exactly 0.1mm, so within spec.
I haven't removed the valves yet, so might still find some drama there, but overall I'm pretty happy. I think replacing the rings, bearings, cam and timing gear should give me a good runner for a while.

One question though: this engine number is 38D31351B. I can't seem to find the proper designation for it on the web. The CR stamp is 8.13:1 and the block casting numbers are WYF 10 and HRC 2411 (2411 is supposed to be a 4.0 or 4.6). Are the Australian numbers different or perhaps missing from the online lists? Any ideas about where I could find the right info?

Here are pics of the cam lobe and timing chain:

I wasn't aware of this thread going on while I was looking at the same things.

I'm a few weeks ahead of you.

Having flanged liners fitted. There were no clear signs that mine were moving but I only wanted to do this once. I'm being charged about $1400 to have the liners fitted and crank machined. New cam, main and conrod bearings, cleaning and some labour are another few hundred.

I've bought a JP Rollmaster timing chain and gear set. Even though my pistons came out looking excellent, I've decided to go with new 9.35:1 standard diameter pistons and new rings.

Heads have been done. Needed 5 new inlet valves because of corrosion and 8 new exhaust valve guides. All new stem seals. With a VRS gasket kit we're up near the $900 mark.

I have to admit, that with the prospect of spending another $800-900 on the last few bits I have mixed feelings about taking this path. I nearly bought a 200,000km old complete Disco for $1500 that was going to serve as a donor for multiple parts and before the rest went on ebay. I'm sure the engine will be lovely once done, but it would want to be for near enough $4K - and that's with me doing essentially all the labour apart from the head reco, crank and block machining. I now have a very good understanding of why Disco's owned by non-spanner twirlers are generally discarded these days as soon as a significant problem crops up.