Removal & reassembly of cylinder liners

[LanciaFin]

Hello,

It's time to have the cylinder liners rebored, so they need to be detached from the engine blocks. According to the repair manual (for 815 engines), they should just slide off, but with my engine this is definately not the case. Are they just stuck in, or are the 819-engines different? Any hint for removal without causing damage? I'll probably have this done by the machine shop anyway, but if there is something to know about, I'd like to hear that.

[gcarenini]

Hi,

did you solve your problem????
I hope that...but if you still have to remove the cylinder liners, would you know that they are just stuck in By oil and lead deposit. My hint is to try to remove as mutch as possible the incrustations on the external side, where the liners is in contact to the block, then you have to rotate 90° the block, to have the cylinder axis in vertical position (remember to place a 20 or 30mm thick wooden list between the block and the floor), now, from th e inside of the block, place a mixture of 50% gasoline and 50% penetrating oil on the liner circumference. Repeat this some times, you have to be patient. After 2 or 3 days try to hit the liner, using an aluminium or copper tube (at least 30mm diameter x 30 cm lenght) in order to avoid any damage to the liner or block and a quite heavy hammer. If the liner is still blocked, avoid to hit again and repeat the first step with penetrating oil. Is a quite long work and you have to be very sensible in order to avoid any damage at the engine block.
When the liner slide off some millimeters rotate 180° the block and place the oil/gasoline mix also from the head side.
This process it work.

Good luck!!!

Kind regards

Giovanni

[LanciaFin]

Thank you very much for this advice! I haven't yet had time to do anything for the engine (have been doing repairs in our 61 year-old house before winter arrives), but actually I could leave the engine blocks to soak in some kind of oil (diesel fuel maybe) while they are waiting. Currently I have everything ready for a complete engine rebuild; new bearings, pistons, valves and guides, oil pump gears, gaskets etc. It's only the time, that I still need...

[flavia1800]

Hi Giovanni

Actuallly I'm very interested to know how to remove the liners as I recently got my revised engine back. Only with a big leak making water flowing into the engine. The leak itself has been localised at cilinder 1 but it is inside so the engine has to be rebuilt. I suspect the leak being between the liner and the block where there is the seal. Liners were not removed but all cilinders honed. Upper side of Cilinder 1 is still about 4/100 mm above engine side so this is ok. I only wonder when/if liners are to be removed or not in case of revision.

ciao Gunther

[gcarenini]

Hi Gunther,
normally, when you remove the cylinder heads, the liners have to be prctically free. If you take a look to the workshop manual, there is a note that prescribe to block, with a bolt, the liners in order to avoid any movement off of the block. I assume that in your engine the liners was stiked, otherwise was not possible to hone it without removing. In normal condition, in case of revision is better to remove the liners in order to change the thin seal between liner and block. If your suspect that the water leakage is between liner and block is true, probably your block is corroded and will be very difficult to repair it in that point. The only way to be sure, will be to remove the head, the liners and then carefully examine the contact surface. Which type of engine you have? 815 or 819/20?
Ciao
Giovanni

[flavia1800]

ciao Giovanni,

it's a 815.300 engine type. I've been told that normally these engines don't have this problem. However it's aluminium and as you say the block can be corroded as well.
But I still believe a leak between block and liner is more probable, because the engine was first cleaned ultrasonicly and secondly, apart from all the seals replaced the only ones that were not were these thin seals and thirdly I know that the liners were not blocked with a bolt when the cilinders were honed as the revisor didn't mention.

I'm actually preparing a 819.400 to start up. If it turns out to be good and to have good compression this one will be installed. The leaking 815;300 will be dismounted and brought back to the revisor as I had a 2year guarantee promised on invoice.
Keep you informed
ciao Gunther

[LanciaFin]

I just received my engine parts from machine shop today, and even though they seemed to have done good work (rebore for 0.6mm oversize, checking and polishing crankshaft pins, removal of oil plugs in crankshaft and cleaning of the passages) it was a bit of disappointment to see that they didn't remove the liners from blocks.

The liners sit very tightly in their places (I briefly tried to remove one, but without slightest success) and I'm now thinking of what to do with them: Reassemble the engine right away, or have some other shop (this was in another town, because local shop didn't "dare" to touch such a rare engine) to remove them to install new gaskets? Has anyone else been in similar situation and reassembled the engine successfully?

And, is there a risk (has it happened) to break the cylinder block when pressing the stuck liners out?

[Michael Findlay]

Sorry I have just caught up with this thread as I have been obsessed about gearbox bearings. I had my engine block treated much the same way. The liners were honed in situ and the protrusion carefully measured afterwards, The block is an open deck design and the liners are usually firmly stuck in place with corrosion making their removal a bit of a risk. My engineer was ready to press them out if there was any sign of movement. The action of the hone is fairly gentle and not enough to disturb the liner. After cleaning and honing the block was filled with water and left to sit but the paper seals appeared to be still in place and doing their job. If there was no leak beforehand, the engine is not likely to leak after this process is carried out. In the case of a leak the liner has to come out and the joint face checked. The badly corroded block in my Alfa GTV was repaired with epoxy and has been fine for five years and 30,000 miles.

[LanciaFin]

I decided to turn a bit creative with this, and took leak detector spray and compressed air. I sprayed the leak detector (which is probably just soap water in spray can) to the seams between liners and block (on the cooling side) ja blew air from the crankcase. With cylinder #1 and #3 no leaks were detected, but #2 revealed some air bubbles, and so I didn't bother with 4. It is of course possible, that the sealing of #2 would be tight after head installation, but I won't take any changes with it - they are all now soaking in penetrating oil.

[LanciaFin]

The liners are removed now. It was quite an effort for the shop I gave the work. At first they called me and told that only one liner was removed and others were too badly stuck. They had put 5 tons pressure and decided to not to press harder to avoid damages. However, a bit later they called that the liners were successfully removed. The trick was not the penetrating oil. Intrestingly, leak detector (Würth brand this time) was the key; they told that the leak detector goes deeper in tight gaps, than real penetrating oil. After applying, the liners got out with reasonable force.

However, keep in mind, that the leak detector is corrosive if left on for long time, and should be used like this only when all the needed means to have the job finished are available. Otherwise it is very likely to turn into glue.

There was no corrosion between the liners and crankcase, only unbelieveable amount of dirt (carbon, tar, whatever.) The liners seem to have kept their shape in removal (tested with new pistons), there was only a little sharp "step" on the bottom inner edge, which I sanded away. The old gaskets are yet to be removed from the crankcases - initially mechanically, because chemicals didn't seem to have any effect on them. Now that the top layer is removed, gasket removers may have a better effect.

Two questions yet: The gasket between liner and crankcase is paper. Should some kind of glue (like Permatex Form-a-gasket #3 which goes between the crankcases) be used? Is the protrusion of the liners measured with or without the new gaskets?