v8 problems

spratty · Post by **spratty** » Sat Aug 04, 2012 5:38 pm

while prepping a replacement V8 for my disco today i found some worrying bits of metal in the sump, which looked a bit like they were part of a piston. so i looked up inside the block and found this:

i think thats bad

so i took the head off that side and popped the piston out. sure enough its broken.

on the other side:

then i noticed something else on the block:

it looks like this liner has slipped down slightly.

bit more info:
its a standard rover 3.9 removed from a Range Rover, its only done 6k miles or so since it had a rebuild.
it did run for a few seconds the wrong way up after the RR it was in tried to do a barrel roll and failed, but its done a few thousand miles since then in a different RR without a problem.

so my questions are:
1) are the other pistons likely to be cracked like this one?
2) can i use the block with that liner the way it is?

thanks

Ian

Darkspeed · Post by **Darkspeed** » Sun Aug 05, 2012 1:02 pm

I don't think that's a 3.9

That looks like a 4.0L unless you blocked up and milled flat the outer set of head retaining bolts.

And as its a 4.0L block the issue with a slipped liner is not a surprise as its a known problem.

As for the chipped piston - could be the result of a casting flaw but looking at the other side of the skirt I am wondering if the liner slip has pinched the skirt.

Andrew

spratty · Post by **spratty** » Sun Aug 05, 2012 1:35 pm

would the engine number tell me what it went in originally?

softdash3.9 · Post by **softdash3.9** » Sun Aug 05, 2012 5:18 pm

Yes the number will tell you

Not much hope for your block without fitting top hat liners I suspect

DEVONMAN · Post by **DEVONMAN** » Sun Aug 05, 2012 5:35 pm

It is possible to get an interim 3.9 block with 10 head bolts and these were made April 1994 on. The pistons in the photo are 3.9's and so are the conrods.

Unless you are going to have top hat liners fitted to the block it would not be worth the risk of using it. The liner could just move again when the engine temp rises,

Cheers Denis

softdash3.9 · Post by **softdash3.9** » Sun Aug 05, 2012 5:46 pm

My interim sepentine engine in my Range Rover Classic has 10 bolt heads, but the block is machined for 14 bolt heads (Engine No 38A low comp 8.13:1)n has crossbolt pads but no crossbolting, std small journal crank, etc.

36D were 9.35:1 Cr, what spec mine was rebuilt too