The V8 Owners Forum -

Hi,
Can anyone recommend a good engine shop in essex.
I'm looking at a couple of options, my 350i has a bad crankshaft oil seal leak.
The compression is down on engine to around 130 psi so will take the oppertunity to get that sorted, hopefully only a hone and rings.
I also have a 3.9 bottom end in the garage which I was going to put in but ... I've read so much about slipped liners and water leaks on these its putting me off.
Whats a good pricefor top hat liners, I've phoned a couple of places and they are around the £900 mark, way to much for me.
Its looking like the only option I have is to stick with the 3.5 engine which seems from what I've read to be more reliable.
Thanks,
BBT.

I have 99% of my machining done here,
http://www.thurstonengineering.co.uk/

Bobbybedtime wrote:Hi,
Can anyone recommend a good engine shop in essex.
I'm looking at a couple of options, my 350i has a bad crankshaft oil seal leak.
The compression is down on engine to around 130 psi so will take the oppertunity to get that sorted, hopefully only a hone and rings.
I also have a 3.9 bottom end in the garage which I was going to put in but ... I've read so much about slipped liners and water leaks on these its putting me off.
Whats a good pricefor top hat liners, I've phoned a couple of places and they are around the £900 mark, way to much for me.
Its looking like the only option I have is to stick with the 3.5 engine which seems from what I've read to be more reliable.
Thanks,
BBT.

As a matter of interest, what sort of percentage of 3.9 blocks have problems with the liners? Trouble with this sort of thing is people talk about faults - but don't mention ones which are fine. 'Cause I've also got a 3.9 lying around, and can't decide whether it's worth the gamble.

ran my 3.9 for 4 years with no probs at all,
and ran 150bhp nitrous through it to,

also got my spare 3.9 still sat on an engine stand in my shed,
must get round to putting it together and sell her on now me thinks

I'm at the same place as you Dave, suppose you only hear about the bad ones. Just don't want to have a load of agro if it does leak.

3.5 and 3.9s have very little problem if any with liners, the 4.0 and 4.6 X bolts are the ones that seem to have the problem, I have been runing a P6 block linered to 93.5 for YEARS and only now is it starting to show signs of wear that will put it out to grass, so Im building a 340hp?? 4.6 using the heads and cam from the 3.9

As Ian says, it is my understanding that 80-90% of the slipped liners are problems are confined to the later large journal blocks and the bulk of the small journal blocks with problems were with 4.2 engines because of a batch problem with the blocks used on this line (cracked block wall castings rather than slipped liners resulting from cracked liner cores) I supose you could always stick a 4.2 crank in a 3.5 block and get something around 3,8 litres (with an overbore).
Best regards
Mike

Thanks Ian, just tried phoning Thurstons, must shut for the weekend, will try Monday, regards.

I have also found Thurstons to be very good they did a great job of metal spraying and re-maching the worn stub shaft on my elan. Gosnays are also pretty good.
I had a liner failure in a 3.5, it also had a twisted con dod in the same bore so I guess it may have hydrauliced etc in the past, in some ways you are better off sticking with the engine you know the history of.
The bores rarely seem to wear so you probably can get away with a light hone and new rings.