Cylinder Liner Height

[mhyphenl 10 1 Cars]

I'm just rebuilding the short engine and got to the point of putting the head back on and noticed that there is some variation in the protrusion of the liners above the block. The liners are transplanted from another block, all have new rubber seals. Anyone got any ideas?

[smithy 1]

have they been clamped down or just pushed down in to the block?

 

could just be they need to be clamped down so they are in to the block fully?

 

if you get a haines manual it gives protrusion checking procedure.

[Sandy 189]

How clean the liner seats are is the main issue usually, but the blocks distort like hell too. You really want to try and get it right to baseline it and massively reduce the chances of problems.

[mhyphenl 10 1 Cars]

How clean the liner seats are is the main issue usually, but the blocks distort like hell too. You really want to try and get it right to baseline it and massively reduce the chances of problems.

 

Thanks for the replies,

 

The block is mega clean as I had it aquablasted in and out, the finish is excellent. Also I thoroughly cleaned the liners and seats and put new seals on. It was cylinder 4 that was about 0.3mm higher than the others while cylinder 3 was too flush. I've swapped them over and the problem has moved suggesting that the liner itself is deeper!? Is there a grading system that pertains to depth? If the block was at fault surely the same cylinder would still be proud!? I'm going to take the pistons out and shuffle the order, (making sure the piston to cylinder pairing is kept) to see if it improves the relative level but if anyone has experienced this of knows somthing please say, even if it seems obvious.

 

Cheers,

 

Martin

[Sandy 189]

0.3mm is a massive difference! I'm not aware of liner height grading, but with Peugeot... you never know! Perhaps consider a new set, at least you can be sure they match and KS aren't hugely expensive.

[lagonda 41]

If you're rebuilding the engine, presumably you've had the liners honed, in which case moving them about shouldn't be an issue, & it wouldn't then be necessary to keep the piston assembly with its original bore. You can also turn the bores through 180 degrees....I had to do a lot of shuffling with mine, but managed to get everything reasonably even.

 

One of my bores had rusted too badly to re-use, so the machinists sold me a new barrel. It was only £30 odd, & I regretted not buying 4. One of those cases where the professionals' kindness was misplaced! Needless to say, the new barrel was prouder than the others wherever I put it...sorry I haven't kept a note of the difference. Torqued everything up according to Forum recommendations (not Peugeot/Haynes) with new head bolts, & it's still running fine 35,000 miles & 5 years later.

[mhyphenl 10 1 Cars]

Ok then,

 

Took the liners and pistons out again, a right pain in the arse as i had all the sump, oil pump etc installed. I've moved the proud liners around the whole engine and its the same at any position, i'm tempted to put them back in the old block just to see what they were like. I even took the seal back off and gave the seat on the liner a really agressive clean with a wire brush but to no avail, made sure the seat in the block was clean too. I'm presuming the idea of having the liners proud just 0.1mm is to make sure the seal is being slightly squashed when the head is torqued up!? I can only think that the liners were adjusted in height to fit the old block and so they dont fit the new, there's no other way to explain it! I guess proud is better than short as they could be skimmed back a little.

If I were to get new, where is the best place and how much do you think it would be?

[wicked 103 3 Cars]

Indeed the liners could be decked before; on the top of the liners sometimes there is a A, B or C mark to indicate there size. If they are still on, they are not decked.

 

Second thing; shouldn't you measure protrusion without the seals on it?

Edited July 4, 2011 by wicked

[mhyphenl 10 1 Cars]

Indeed the liners could be decked before; on the top of the liners sometimes there is a A, B or C mark to indicate there size. If they are still on, they are not decked.

 

Second thing; shouldn't you measure protrusion without the seals on it?

 

Can anyone confirm for definate measuring the liner protrusion without the seals on!? if this is the case I'm screwed as two of the liners will be short! My liners don't have any marks on them, all my pistons are B! I did wonder why there were no marks! This is going to turn into an expensive disaster isn't it!

[wicked 103 3 Cars]

I donno if (aftermarket) liners always have the markers on the top...

 

Can you put both blocks side to side to compair their heights?

Edited July 4, 2011 by wicked

[wicked 103 3 Cars]

Elsewhere on the forum:

 

Take another 0.0015" off the block. The gasket will take up the difference in liner heights. They will still all be within spec. Protrusion should be checked without seals and block & liners squeaky clean. Provided they are square I think all will be fine.

[mhyphenl 10 1 Cars]

Elsewhere on the forum:

 

Quick favour, can you post the link to that conversation, I'll have to get something done overall as there's no point spending a load of money on barings and seals, honed liners etc and then not get a proper seal from the head gasket! Looks like I'll need to get the block shaved and two of the liners to get it spot on!

Damn it, I knew things were going far too well!

[pug_ham 241 3 Cars]

Can anyone confirm for definate measuring the liner protrusion without the seals on!?

Yes, you definately measure the liner protrusion from the block without the liner seals fitted.

 

Even the haynes manual tells you this is the way to measure the liner prostrusion.

 

g.

[mhyphenl 10 1 Cars]

Yes, you definately measure the liner protrusion from the block without the liner seals fitted.

 

Even the haynes manual tells you this is the way to measure the liner prostrusion.

 

g.

 

Thanks so much guys, massive help as usual. Was just reading through the manual as you replied! That means I have 2 short liners not 2 long ones. I'll measure by how much tonight and post tomorrow just to get opinions on how far to go or wether its just worth getting new! Where would you go for new??

[mhyphenl 10 1 Cars]

Many thanks to Pug_ham. Your very clear instructions to measure the protrusion without the seal solved the mystery. The manual clearly states that for the early engines you measure without seals but on the XU section its more vague, it tells you to replace the seals then insert the liners then measure but im sure now that it's just lazy writing having described in more detail in the previous section.

 

Pug_hams knowlege solved the problem because without seals everything was spot on but with seals the height were all over the place. Turns out that Pug had sold me 4 seals but 2 different sizes!! Causing 2 of the liners to stick up by more than 0.6 of a mm!

 

Yesterday I had visions of needing some skimming of the block and 2 liners ground down, now i just need a set of liner seals that match. Peugeot have replaced the part number for these and it looks like they now come in a set of 4 so hopefully they'll work out fine. The only pain is they'll take a week! Did someone on here say they were selling them that might get them quicker??

[pug_ham 241 3 Cars]

Glad its not as bad as expected & you've sorted it easily.

 

I'd be surprised to see a mixture of liners causing such great differences that you had to get the block decked for them to be within range with good seats, the manufacturing tolerances surely wouldn't be that bad.

 

g

[Duroc 2 1 Cars]

The reason the liner height is measured without the rubber seals in place, is because the seals sit on a beveled (45deg) edge on the block. As the head is clamped down onto the block, the seal compresses to a certain extent, until the outer edge of the liner flange (that the seal sits under) makes contact with the block. Take a look at this

[Sandy 189]

The seals don't hardly need any clamp... the protrusion is there to provide good fire ring clamp over the whole temp range, because the block will grow slightly more than the liners at normal running temp. Over doing it gets you into block and bore distortion.

[lagonda 41]

Glad you've got it solved. Wouldn't have thought using different thicknesses of the "O" ring liner seal would cause any problems...provided both are correct for the engine, they'll compress to the space available. The only pressure they have to withstand is that in the cooling water system....10-12psi?

[smithy 1]

Many thanks to Pug_ham. Your very clear instructions to measure the protrusion without the seal solved the mystery. The manual clearly states that for the early engines you measure without seals but on the XU section its more vague, it tells you to replace the seals then insert the liners then measure but im sure now that it's just lazy writing having described in more detail in the previous section.

 

Pug_hams knowlege solved the problem because without seals everything was spot on but with seals the height were all over the place. Turns out that Pug had sold me 4 seals but 2 different sizes!! Causing 2 of the liners to stick up by more than 0.6 of a mm!

 

Yesterday I had visions of needing some skimming of the block and 2 liners ground down, now i just need a set of liner seals that match. Peugeot have replaced the part number for these and it looks like they now come in a set of 4 so hopefully they'll work out fine. The only pain is they'll take a week! Did someone on here say they were selling them that might get them quicker??

 

 

the liner seals i got from pug came as set of 4 under different part number than before,total cost is around same as one seal under old number.

 

0112 A7 is the number if you do need it?

[mhyphenl 10 1 Cars]

the liner seals i got from pug came as set of 4 under different part number than before,total cost is around same as one seal under old number.

 

0112 A7 is the number if you do need it?

 

Yup got them now! The guy at Peugeot wasn't totally sure if it was a pack of 4 or not so i ordered 2 to go with the 2 correct ones i had. I now obviously have another 8 as it was 2 packs of 4! Good to have spares though, I'm putting it all together again tonight so the next step will be the head, what will that throw at me!!?

 

Once again cheers everyone.

Edited July 11, 2011 by mhyphenl