corrosion in liner seal

[figleaf11]

Putting together a 1750 and I notice some slight corrosion in the chamfer of one liner seat, question is: can this be dealt with with a slight application of metal filler (dura seal etc) and hold? Anyone dealt with this?
Thanks board.
Ralph

[Gordon Raymond]

Yes indeed Ralph. Very familiar with this problem. Several questions. How deep are the pits? Where are they located? One or all four?
First, I had a friend make me up this VERY special Alfa tool, pictured below. He was going to charge me $17,000+ but decided to give it to me for my highly technical scratch pad drawings, and patent rights. All that's involved is a cut down and, in this case, bored liner, very slightly sanded on the bottom skirt, so it will slide in and out of the block easily. This is to reduce the weight of the tool, and allow ease of use. It is pinned across the top with a swiveling 1/2 inch drive. In use, the lip is smeared with a slurry or paste of borax, the tool inserted in the block and turned (a lot). It polishes the "O" ring surface with minimal material removal. You can tell it's working as the borax paste turns black. The advantage of using borax, is that it dissolves in hot water and leaves no abrasive residue in the block. Now, with deep pits located right at the "O" ring seat, a dab of JB weld, cut with a razor blade while still not completely set up, to close to the aluminum's shape, then an attack with the VERY special tool, will refresh the seat to like new. The pits must be 100% clean in the bottoms for the JB to stick in there for good, like a dental filling. I use dental picks, and a "Q-Tip" dipped in an aluminum welding prep acid, though my tool builder claims as good a result with a Peremetex Grey sealant in the pits. Either way, the tool is a long awaited blessing. Order YOURS now, form Alfar7 here on this board, (Richard Jemison).

[kengta]

Quote:

Originally Posted by Gordon Raymond Yes indeed Ralph. Very familiar with this problem. Several questions. How deep are the pits? Where are they located? One or all four? First, I had a friend make me up this VERY special Alfa tool, pictured below. He was going to charge me $17,000+ but decided to give it to me for my highly technical scratch pad drawings, and patent rights. All that's involved is a cut down and, in this case, bored liner, very slightly sanded on the bottom skirt, so it will slide in and out of the block easily. This is to reduce the weight of the tool, and allow ease of use. It is pinned across the top with a swiveling 1/2 inch drive. In use, the lip is smeared with a slurry or paste of borax, the tool inserted in the block and turned (a lot). It polishes the "O" ring surface with minimal material removal. You can tell it's working as the borax paste turns black. The advantage of using borax, is that it dissolves in hot water and leaves no abrasive residue in the block. Now, with deep pits located right at the "O" ring seat, a dab of JB weld, cut with a razor blade while still not completely set up, to close to the aluminum's shape, then an attack with the VERY special tool, will refresh the seat to like new. The pits must be 100% clean in the bottoms for the JB to stick in there for good, like a dental filling. I use dental picks, and a "Q-Tip" dipped in an aluminum welding prep acid, though my tool builder claims as good a result with a Peremetex Grey sealant in the pits. Either way, the tool is a long awaited blessing. Order YOURS now, form Alfar7 here on this board, (Richard Jemison).

[figleaf11]

Gordon, thats super! I have VERY slight pitting in only one liner bore, Block is clean. Had it tanked, thats when pitt showed up. Think a dab of grey will do it. That tool is Toooo much, how clever!
Ralph

[Graham D]

Veeeerry clever tool! But did you get a good look at Richard's toes?????

[Alfar7]

Correction! Did you guys notice Gordon`s toe nails?

[Gordon Raymond]

Those are Phoebe's toes, Gordon's wife. (Nice Huh?)

[figleaf11]

Are they Alfa or Ferrari Red?

[Gordon Raymond]

Quote:

Originally Posted by figleaf11 Are they Alfa or Ferrari Red?

[1750GT]

Gordon, does this tool have a chamfer at the root so that the chamfered edge on the block is also cleaned-up? My block has some pitted areas on the chamfer and I was wanting to clean this up somehow.

[Tifosi]

Sorta related query:

Rather than patching pits and corrosion, would it make even the remotest sense to overbore the sleeve bores, then refit to size with steel rings bonded in, thus all but permanantly eliminating the pitting issue? (unless of course the different expansion rates of the metals would make more of a mess than it would help)

[Gordon Raymond]

Darren, Many years ago, I was taught that Alfa wet liners are a particular alloy to move with the block and head. Ferrari uses a dry liner in the old 12's that was supposed to be the same alloy, and work the same way. Now, I don't know how true this is. When you subject an Alfa four to racing stresses, a grove in both the top of the liners, with a like grove around the combustion chambers, that the fire ring in the head gasket squishes into, forms an "O" ring like seal. This prevents changes in expansion characteristics between the liners and head from causing combustion chamber leaks. It does work. The old V12 Ferrari's all used relatively low compression ratios, but in racing, like work can be done. So, perhaps things don't really move "together". We have ALWAYS been cautioned to warm these engines up gradually, and there are an awful lot of threads here about head torquing. Also, beside the usual suspects, there are many other sources for custom liners. Some of these liners (if one wants to pay for them) are made of all sorts of strange sounding alloys. They must have equally strange expansion characteristics as wet liners in an aluminum engine. Finally, Alfa must have changed the aluminum alloy, blocks have been cast of over the years to keep up with new, efficient production techniques. It still seems like multiple sleeves might be a cause for more problems, who knows?
I have seen a rare Ferrari block repaired, after a blow up, with oversize dry liners after the aluminum was welded back together, and the dry liner bores cut oversize. No reason why this could not be done with an Alfa wet liner if you wanted to go to the expense of custom liners. It might even be possible to machine the lip seal recesses deeper and epoxy aluminum rings back into these recesses to bring dimensions back to stock. Many drag race engines run with different amounts of epoxy filler in the bottom of the water jackets. Never tried this either, but it may work, allowing use of stock liners.

[Gordon Raymond]

Quote:

Originally Posted by 1750GT Gordon, does this tool have a chamfer at the root so that the chamfered edge on the block is also cleaned-up? My block has some pitted areas on the chamfer and I was wanting to clean this up somehow.

[Alfar7]

Not everybody can afford my $17,750.00 tool. Yes everything cost more today
But for the rest of the Alfa world (all but Gordon) the easy solution is a thin wipe of "Super Blue" RTV around the block below the "O" ring sealing area.
Actually a thin wipe of it the day before in the "O" ring seat area, wiping so that it only is in the "pits", letting it cure, then the very thin wipe below (so it does not get on the "O" ring will absolutely seal the motor. No reason to get excited about a small amount of pitting unless it is excessive. If so you best look at your studs as well
You understand Gordon`s a "bit" "Anal"

[Gordon Raymond]

I have also found Richard's used chewing gum, the green breath stuff, NOT the pink bubble gum, also works well in the larger pits, but unfortunately, it is way too expensive for the average engine builder. The special tool, designed by ME, but manufactured by Richard, is less costly now that the prototype development and patent search ($17,750.00) has been completed. As the patent rights were only good for 10 minutes, or one tool use, (to see if, in fact, it worked) Richard can now manufacture these quite reasonably. You must understand, his production is necessarily crude, due to limited machining abilities and lack of proper tooling. My more anal production, will not be in full swing for several more decades, but is of MUCH higher quality. Meanwhile, if interesting Alfa tools that make irritating jobs easier are desired, I strongly suggest you contact Richard, at RJR racing for an economical example of my fine tool, as he IS in fact, a good friend!