A few days ago I posted a picture gallery of a portal axle conversion. Here's another photo gallery, this one showing a V8 engine overhaul on a Bentley which has a similar design block to a Land Rover.
I've shown a Bentley because it's an example of a motor for which we can no longer buy repair parts, or for which parts are unreasonably expensive. As Land Rover V8s age we'll see these same things here . . .
Until last year Land Rover supplied inexpensive short blocks for repair. Now the supply of blocks is drying up, and costs are rising. The conventional wisdom had been that when Land Rover engines overheat the liners drop and the blocks are junk.
Given a $1000 new block as a replacement that statement made sense. But for $4000 (the cost of some new blocks today) it's possible to repair those dropped liners.
In addition, the new blocks do not have the same balancing as the original ones and we have had several complaints from finicky owners that untimately led back to balance of the replacement engine. When we rebuild an engine we can balance it properly, avoiding this issue.
I think repair of dropped liners is going to become the norm in the future, and these images show how it's done. I'll explain in brief before sending you into the photos.
1 We strip the block and tank clean it.
2 We bolt plates to the cylinder head surfaces and pressurize the oil and coolant galleries with air, and we check for leaks. That allows us to identify cracks.
3 We also use chemical crack check on accessible areas.
4 We pull any slipped or damaged liners, and we pull liners from any locations where we find cracks
5 We bore the liners if needed, or just hone them
6 We crack test, shot peen, measure the crank and rods and grind or rebuild as needed.
7 We refit liners and fit the pistons, either standard or oversize
8 We continue with assembly
Pulling all the liners is a big job, a day's work. But is new blocks are costly or unavailable it makes sense. Cranks can be ground to undersize, or they can be welded up and then cut back to standard. Rods can be rebuilt by shaving the big end cap then reboring to ensure perfact length, straightness, and bore. Blocks can be trimmed flush on the deck and we can install flanged liners that can't drop. We can linebore the main bearing journals to correct slight twists.
Given one of the responses to my last photos . . . I'll close by saying that we are not putting these images up as a means of soliciting work. I've put quite a bit of effort into supporting the Land Rover community because they are my favorite vehicles and I am fortunate to have a shop where I can watch all sorts of work being done and I have time to write about it. We currently answer questions for Land Rover owners worldwide, and I publish articles about things like this in many Land Rover magazines. If you'd like to try a rebuild like this in your area drop us a line and we'll try and provide more concrete advice for your local machinist. The techniques shown here are within the capabilities of any good well equipped machine shop and master machinist.
The pictures are here: http://www.pbase.com/robisonphoto/bentley_overhaul