Liner stand in question

[andyblackman777]

Hi all I’m wondering if someone could help me. 
I have an engine that has stood for some 20 years. I decided the other day to take it apart to see what condition it’s in. Remarkably the cylinders look in good shape, hone marks still evident.
All the liners are pretty much flush with the block. When rebuilding and dry fitting I understand that there is a small stand in where the liners are below the deck. My question is when sealant is applied and the head is torqued down, will the liners then be flush? Which would explain why that is the case on disassembly, or maybe this engine has previously been rebuilt incorrectly??
Thanks in advance 
Andy 

[Thartje]

The liners are slightly below the deck height because the head gasket makes up the difference in space. If replacing the liners you can order them slightly taller ones to avoid head gasket failures, especially if increasing boost. That is the route I went on my rebuild.

[jonwat]

8 hours ago, Thartje said:

The liners are slightly below the deck height because the head gasket makes up the difference in space.

Different to the four cylinder engines then where the liners always stood proud of the block in order to ensure head gasket sealing.

[andyblackman777]

Thanks guys. I was thinking that maybe the stand in was there when dry fitting so when the sealant is applied they are then flush. Maybe mine has been previously rebuilt that way 🤔

[Thartje]

The heads should be torqued down with a head gasket in place when the liners are installed. it will seat the liners all the way down so shouldn't be sitting on any of the sealant.

[ekwan]

I always thought the liners should be just a little proud of the surrounding block, so that there was a little crush when the head with the gasket was torqued down???

[Thartje]

5 hours ago, ekwan said:

I always thought the liners should be just a little proud of the surrounding block, so that there was a little crush when the head with the gasket was torqued down???

Not on the V8 Esprit engine.

 

[andyblackman777]

16 hours ago, Thartje said:

The heads should be torqued down with a head gasket in place when the liners are installed. it will seat the liners all the way down so shouldn't be sitting on any of the sealant.

Hmm wonder why mine are flush…..

[Thartje]

1 hour ago, andyblackman777 said:

Hmm wonder why mine are flush…..

Already installed and sealed? Or new liners are flush?

If the engine was rebuilt the block could have been decked down or taller liners maybe have been installed.

I used taller liners on my block to close the gap. I had them machined .003 taller.

.004 is a tiny amount. It may appear flush unless you're using a dial gauge to confirm.

For reference. This is the difference.

[mike_sekinger]

Westwood have an existing design for the taller liner - this was requested by Andrä some years ago

L5188 is the standard height in ductile iron.

 

[Thartje]

8 hours ago, mike_sekinger said:

Westwood have an existing design for the taller liner - this was requested by Andrä some years ago

 

L5188 is the standard height in ductile iron.

 

 

How much taller were Andra's liners? Mine actually have a different part number but were .003" taller.

[andyblackman777]

It’s an engine that I have that has been stood for 20 years. I have no idea of the history apart from 39k written on the oil filter and it has the early front cover.  I’ve not touched the liners just removed the cylinder heads so far. So Liners currently  installed and sealed. Just making a bridge so I can measure with a dial gauge. 
I’m debating what to do with it….

[mike_sekinger]

9 hours ago, Thartje said:

 

How much taller were Andra's liners? Mine actually have a different part number but were .003" taller.

According to Westwood:

L5188: OEM height above spigot - 61.05mm

L4893: Andrä spec - 61.20mm

Give the OEM stand-in of 0.10mm, the Andrä liners have a nip of +2thou proud of the deck face.  This was based on his experiences racing 900-series engines and has served well.

Your spec is -1thou below the deck face, right?

 

[andyblackman777]

 I’m interested to know why it’s designed like that if it works the same with no stand in or even some nip. ?

[Thartje]

14 hours ago, mike_sekinger said:

According to Westwood:

L5188: OEM height above spigot - 61.05mm

L4893: Andrä spec - 61.20mm

Give the OEM stand-in of 0.10mm, the Andrä liners have a nip of +2thou proud of the deck face.  This was based on his experiences racing 900-series engines and has served well.

Your spec is -1thou below the deck face, right?

 

Ah, this make sense. Yes, mines are just below the deck height. Interesting he had his above the deck.

[Thartje]

10 hours ago, andyblackman777 said:

 I’m interested to know why it’s designed like that if it works the same with no stand in or even some nip. ?

The gasket has some compression so would still be snug around the cylinder tops if there is a .004" gap. For mass production its probably safter to have the liners below the deck then above just for alignment and even clamping, just the first thought that comes to mind but I'm sure there are plenty of arguments either way. I had my liners raised as I'm running more boost but I don't think I would go above the desk height. I don't see the need.

[andyblackman777]

Well after sorting some more accurate measuring equipment I do indeed have a small stand in. Straight edge doesn’t cut it. An interesting topic though. 
 

[andyblackman777]

Is this to do with thermal expansion of the sleeve i wonder. Does alloy expand less than Iron/steel? I still find it an odd idea having the gasket take up a gap that's deliberately there. 

Also any tips on getting all the crusty old sealant off the block bores without damaging them 

 

[drdoom]

Try acetone for such cleanups, these sealants are polymer based as far as I know. Might do to cut that with some methyl hydrate in order to reduce volatility, increase working time. Nitrile gloves and absorbent filter mask highly recommended.

Cheers

[Chillidoggy]

15 hours ago, andyblackman777 said:

Is this to do with thermal expansion of the sleeve i wonder. Does alloy expand less than Iron/steel? I still find it an odd idea having the gasket take up a gap that's deliberately there. 

Also any tips on getting all the crusty old sealant off the block bores without damaging them 

 

Frost’s Strip Gel.