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Sleeved Blocks

6K views 38 replies 15 participants last post by  Lonewolf 
#1 ·
As some of you may remember I had my engine rebuilt at Geoff Steel Racing in the North East of England. The engine had now failed with less than 20k miles, the bores are oval and there are cracks extending down to the crank. Geoff Steel have not shown any interest in the engine now that I have returned to NZ. The car has been off the road now for several months and I really miss it but I'm having trouble deciding what to do.

I'd like to build another engine but I'm reluctant to fork out another telephone numbers worth of cash for an engine that won't last. So I was wondering, what has been the experience of others in over boring or sleeving?
 
#3 ·
And how much power were you making? Did you have a supercharger? Boost level?

I'm surprised to hear the sleeves cracked under normal use. Do you track the car?
 
#8 ·
Someone ran too lean?
 
#9 ·
By 'oval bores' do you mean tapered? And by 'cracks extending to the crank' do you mean cracks in the cylinder wall? What was done during the rebuild? Is there a thread on it?

To your question, I think sleeving has been successful on higher-powered forced induction builds so if you're staying NA, as I would, you should be fine if it is done properly. I can't help you on the proper way except to suggest a search of the forum. I know there are threads that talk about it.
 
#10 ·
Been running a sleeved engine since 2006 w/o problems, ca. 65000 km on it.
 
#11 ·
Blue Thunder, how many miles on your build? I made 20k miles after sleeving until it began to lose compression.

The bores were oval, not tapered and the cracks were between the cylinders in the parent material that was left. We pulled the liners out to see this, they extend all the way down into the 'webbing' supporting the crank.

No obvious signs of either detonation or lean running.
 
#12 ·
65000 km is approx. 40.600 miles.
 
#14 ·
It was done in Sweden, not sure by which shop since it was subcontracted from the company that built the engine.
 
#15 ·
The block machining required to fit sleeves properly has to be very precise. It requires a level of competence alien to most automotive machine shops. I wonder if Geoff Steel Racing farmed it out to one of those. The press fit of the sleeves in the bores may have been too heavy. Can you measure what is was?

Here's a pic I found of an S62 block being sleeved by RK. Was yours cracked down the thin walls separating the bores?

Malcolm

Auto part Metal Steel Engine Pipe
 
#21 ·
Yes there are two measurements, this is the second of the two with the first set to zero.

The block is toast and my car is dead although it ran amazingly well right up until it was torn down. I wonder how many sleeved S62 engines are on this forum?
 
#22 ·
That bore gauge seems to be showing the bore in line with the crank is ~0.013" LESS than the bore 90 deg to the crank. That is horrible. And it's hard to see how it could have degraded to that point in service so it's like the block was assembled like that.

So are the incompetent/crooked bastards going to get away with it? Pretty hard to hold their feet to the fire from NZ, I guess.

Malcolm
 
#29 ·
Peter, the pistons are from CP but I'm not sure what the material specification is.

68Fb, your comments are the same as the engineers who stripped it, they were surprised it still ran and hadn't seized.

So I'm wondering how other sleeved blocks are standing up? What other options are there for rebuilding the S62?
 
#31 ·
Thats what i thought although i was really trying to find out about longevity with these builds. My engine ran strongly for 20k miles before developing a misfire and i guess I'm gun shy about spending on another rebuild if it won't last any longer than this!
 
#33 ·
The stock block is capable of 600 hp and maybe a little more. You were running a little less than 500. So what was the thinking about going with sleeving in the first place?

Regards,
Jerry
 
#35 ·
I appreciate that. But I was wondering WHY you sleeved the block? That is generally done for high horsepower applications because the cylinders are so close to each other, the walls are very thin. This was partly a consequence of punching out the 4.4 liter block to 4.9.

But since the stock block has proven reliable for over 600 crank horsepower and you were running less than 500, I was wondering what the purpose was for sleeving the block? Did you plan on forced induction later? If not, it seems you can easily run a stock block and not worry about sleeving in the future.

Regards,
Jerry
 
#36 ·
Jerry if you or anyone else have got a good used short block - let me know!

Sleeving was simply the only way to salvage the existing block. And with many used blocks having scratches in the bores at even low miles I wonder what other good options exist for reconditioning these bores.
 
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