Livio928

Anybody know of a shop with a Sunnen machine capable of honing a 928 S4 Alusil block? I have two actually that I would like machined and honed after rod bearing failure. There are scratches in the side cylinder walls that need honing. My contact for diamond hones, couldn't get a hold of them so now I am back to looking for a shop that can machine them.

I am in Hamilton, so closer the better, but not opposed to travelling to Toronto or surrounding area.

My final option would be to purchase another bare block in decent condition (least favourite)

JimV8

I don't know what equipment they have but it's an automotive machine shop with a good rep.

Beatty and Woods Ltd
1980 Boylen Rd Malton, ON L5S 1P5‎
(905) 405-850

Ernie J

Livio, you can not hone out scratches in the bores. You must bore and hone the bores and fit oversize pistons. We have this issue with 944 blocks. Bore and hone ,fit new pistons is wht we do.

Livio928

Hi Ernie,

That is what I was lead to believe. Who does this type of work on the Alusil blocks? If the scratches are light, can you go with oversized rings instead or after the boring process it that already too big?

justaguy

This has been discussed on here before. the type of hone and procedure is in the WSM. You have to hone the block and then there is solution that has to be used to etch the aluminiumn and expose the silicone particles. Its complicated there are some guys in California who have experience with this. I'm interested if you can find some one North of the border because I have a couple of engines to do as well.
I was thinking of buying a hone but hav'nt had time to look into it.

Livio928

As you said, there are others who want to get their blocks done as well. I have two available for honing, I was thinking of keeping one as a spare or selling it as a newly machined block.

The problem that I am afraid of is that I would need to purchase oversized pistons. With 8 pistons at $500 each, it is getting pretty darn expensive to do all cylinders. Obviously, i would only machine the cylinders that need machining and leave sleeping dogs lie on the the other o.k. cylinders.

Not sure if there is a benefit to honing good cylinders anyway. Ernie, do you have any input on this through your experieneces with the 944s et al?

Ernie J

Livio, If the engine is apart, if the bores are in reasonable shape then a light hone can be done. IF the bores have heavy scratching then you must fit new oversize pistons.Do it right once, the bores do not heal themselves.For all the work of taking an engine apart $500 per piston is about right. Boring the block is $575 for 4 cylinder engine. block must be clean.

Livio928

Ernie, the 928 engine is notorious for the #2/#6 rod bearing failure. I was visited in the #6 cylinder. My question is this - do i have to bore all of the cylinders to oversize or can I limit it to just the scratched cylinder. From my understanding the oversize pistons are the same weight as the standard pistons so on the surface I don't see a problem, but I have never done this before. The other cylinders look quite good.

Who is capable of doing this work in the Hamilton or GTA area since the block is made from Alusil?

Livio928

Cool. Can I send you photos as a preliminary and if all looks good, then I can bring you the block? The piston was going to be purchased from one of the big three(four) 928 suppliers. If you could supply me with a price of the piston, that would also be great. PM me when you have a chance. There are a few of us that need to bore blocks, so this could work out to additional work for you Ernie.