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what are the chances that a liner would recide into the block, thus being to low to seal to the head gasket and head.
 

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How about the seal between the liner and base of the block not being installed properly, and letting the liner drop.

But then you'd have water from the jacket in your oil.
 

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They don't get shorter, or sink into the block by themselves. You may have always had one short liner, particularly if the engine was rebuilt. At sometime someone may have cut one seat slightly deeper cleaning corrosion. Warped blocks in 750 and 101 1300's will sometimes do this when the head, sump and crank are removed, but in 45 years I've only seen that once. The actual design is such that the liner "O" ring does NOT prevent the outer liner lip from contactin the aluminum block ledge. The "O" ring is completely compressed into the corner of the flange and seat. Without "O" rings, there should be uniform liner protrusion above the block deck.
From my experience.
 

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Richard Jemison
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liners

The liners don`t have to be "proud"of the block surface. The thickness of the fire ring will seal them even if they are a couple of thousandths short.

If they are short either the liner is short or the base was machined differently as to distance fron top of block/crank centerline whichever is the set up point.

You can`t measure them without removing the o ring and clamping all of them down on both sides.
 

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Thanks Richard. Your answer is better than mine!
 

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while we are on the subject; I am at the point of having the sleeves of my 72/2000 mic-ed/measured by a mechanist to see if they are uniform all around. Reason being(?) you ask: the motor has 90K on it and had not been driven in 20 years. Most of the miles were highway miles. When my mechanic tore down the motor he was amazed at what good condition it was in(I changed the oil every 3k miles religiously). He said the valves in the guides were impeccable given the age. I believe that if the sleeves measure even all around I can probably get the motor back in good shape by honing the sleeves, new rings, grind and lap the valves, new valve seals and call it good. I hope I'm not fooling myself by my economy approach to rebuilding this motor rather than going with new sleeves and pistons etc. Now, with that said, I am wondering if my scenario works out if it would be a must that the O rings at the base of the sleeves be replaced? Thanks for your expertise....
 

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"O" rings at liner base are a replacement item with engine disassembly. Further liner seat cleaning and examination of block liner seat ledge is wise as this is an area where corrosion can be an issue.
 

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corrosion?

"O" rings at liner base are a replacement item with engine disassembly. Further liner seat cleaning and examination of block liner seat ledge is wise as this is an area where corrosion can be an issue.
I drained the block before I put it to bed way back when(I'm a one owner/me). Wouldn't antifreeze be the source of corrosion?
You may not know this but would those liner O rings come in a complete gasket set from most of the parts places?
 

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Unfortunately, even with anti-freeze, there is still sometimes corrosion found on the block (aluminum) liners seats from exectrolysis. This is also a goor reason to use distilled water in non-premix anti-freeze, use a top quality anti-freeze for aluminum blocks, and change it every 2 years or less. Anti-freeze itself is not a corrosive.
A good quality gasket set should include liner "O" rings. Inquire before purchase.
 

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In industrial applications, true "distilled" water is considered very corrosive. "De-ionized" water is essentially a vacuum for donor ions from whatever it is touching. De-ionized water can do a number on stainless and aluminum.

Now, whether what is sold as distilled is really pure is another question.
 

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What you are looking for Don is water without dissolved minerals. Anti-freeze tends to create an ion nuutral solution. I an NOT a chemist, but racers traditionally choose whatever passes for distilled water to avoid mineral deposits on liners that does interfere with heat transfer. As you know, a 50/50 antifreeze / distilled water solution has better heat transfer qualities than either 100% distilled water or 100% anti-freeze. On many racing venues, anti-freeze is not permitted as spills cause a slippery track condition. Racers want the best heat transfer pissible, using water. Ideally water without disolved minerals.
From my experience, and only my opinion based on that experience.
 

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Centerline usually has the individual O-rings in stock. However I can't imagine you don't need the entire gasket set. How do you get the liners out without taking the pan and the head off?
 

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gasket set

Centerline usually has the individual O-rings in stock. However I can't imagine you don't need the entire gasket set. How do you get the liners out without taking the pan and the head off?[/QUOTE

As stated above the motor is torn down.
 

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If torn down, the "O" rings are a "must-replace" item. They should be in a quality gasket set. Ask before you buy. They are available from many sources.
 

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WRT corrosion from coolant in these motors. Speaking from a position of a complete lack of knowledge I can speak authoritatively on this...

I use my local tap water in my race motors. With a healthy dose of Redlines "water wetter" I am prohibited to use antifreeze by the rules.

But, every time I drain down my motor I empty its coolant into a freshly cleaned drain pan, then store it in a sealable 5 gallon jug. I do this because in my experience the things that make water corrosive are dissolved gasses (oxygen) and its thirst to dissolve the metal and salts of your block and put them into solution.

So I consider the coolant I take out, "Full" or saturated. I use a paint style filter when I put it back in to finely filter any contaminants and then don't pour in the last bit where any detritus lies. I use makeup water to top off the coolant.

I have also started using "zincs" somewhere in my cooling system to give the coolant something to attack that is not my block. This was after taking apart a 2 liter Nord that had one and noticing the complete lack of corrosion on the inside.

The engines I have seen that are corroded the worst internally are the ones that someone drained most of the coolant out and left them open, they are horrendous.

Greg
 

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I have also started using "zincs" somewhere in my cooling system to give the coolant something to attack that is not my block. This was after taking apart a 2 liter Nord that had one and noticing the complete lack of corrosion on the inside.
IAP used to sell zinc water passage plugs that replaced one of the ones that screw into the top of a cylinder head and acted as sacrificial anodes. I don't recall seeing them in the past few years.
 

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IAP used to sell zinc water passage plugs that replaced one of the ones that screw into the top of a cylinder head and acted as sacrificial anodes. I don't recall seeing them in the past few years.
That's exactly what the motor I referred to had on it.

Greg
 

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Sounds like a business opportunity for someone.
 
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