Cylinder head gasket water leaks

[rogermark]

Hello Everyone
I have re-built my Flavia engine and when filling with coolant I found the water leaks on the top side of the engine on both sides. The engine has not been started yet.
I used new gaskets ( from Emporio Ricambi ) new seals under the liners and with the liners having .05 mm raised above the block.
I cleaned the threads and bolt faces as recommended in the manual and torqued them in stages to the recommended torque and sequence.
I also used a gasket sealant ( Loctite No 3 non hardening )around the water passage faces on the block and head
I will have to take the engine out again and find the problem and get new gaskets but I am looking for any tips or advice.
Why does Lancia recommend fitting the head bolts free of lubricant..?? Does anyone know of a stud conversion…my son cured the head gasket problem in his Toyota Cressida by going to studs

Any help or advice would be much appreciated

Regards
Roger Michie
Newcastle Australia

[flavia1800]

hi Roger,

just a few things you should check...do they only leak at the top side? Is there water in the heads? have you had the heads checked by a revision company? When checked for cracks they are put under pressure. Have they been flattened? Are you sure they are free of cracks?

I do seem to have the same issue with my spare engine: water was in the heads. These have been dismounted and are at the revision company for a check-up now. Iµm still waiting for the result.

regards
Gunther

[gcarenini]

Hi Roger,
have you checked the planarity of crankcase?
Kind regards

Giovanni

[LanciaFin]

Hello Roger,

Have you skimmed to heads and/or blocks? I don't know what's the length limit for bolts when skimming the heads of Flavia's engine, but in some engines such a case sometimes causes the bolts to reach the bottom of the threads before correct torque. This can be cured with additional or thicker washers (don't use the regular soft washers) or shortening the bolts if possible.

I'm not sure, but I don't think that Loctite no 3 is in its right application on head gaskets. If you want some additional sealant, VHT Copper gasket cement is the one that has commonly been applied on head gaskets. I've been using it succesfully on both stock and turbo-charged engines, and so have some more serious engine builders here in Finland.

I don't know either why Lancia has recommended unlubricated installation. Any ideas?

[FL30]

Aluminium threads are sensitive to overturning, The recommended torque for fixing a bolt is related to the required tension of the connection. The torque needed on the other hand is influenced by the friction of the threaded connection. If you reduce the friction between the two threads (bolt and hole) you run danger to overcharge the aluminium thread, dragging the thread out of the aluminium part.

When I remember correctly, fixing torque values are always given for dry connections, aren´t they?

Hubert

[gcarenini]

Hubert,

the threads in the crankcase are Helicoil type, but, in any case, you are correct, the fixing torque values are always intended in dry conditions, not only for Lancia engines.

Kind regards

Giovanni

[rogermark]

Hello Everyone
Thanks for your comments and advice
I've got one head off so far and now that it is cleaned up I can report that the head is still flat and that the liners are 1 to 2 thousands proud of the block.
I've been researching these issues on the net and have found that the consensus is that the composite gasket supplied by Emporio-Ricambi should be installed on clean dry surfaces. That means that I should not have used any sealer .
And that it is adviseable to use plain distilled water for the first fill of the coolant. This is because of the low surface tension of the anti corrosion additives which enable the additive to find any tiny way for the water to leak out.
I'm trying to find out if the gaskets I am using are the type which is classed as "torque once" meaning no re-torque is required after first running the engine.
I look forward to your futher comments and thank you all for your interest
Roger

[Michael Findlay]

Hi Roger

I found a similar leak on the top side of the head as indicated in your picture. It was not as extensive but worrying nonetheless. I ran the engine for a hundred KMs or so and watched the leak which did not get any worse. I then re-tourqued the heads and the leak was banished forever. I guess the lesson here is that the open deck wet liner block is a little flexible and may distort when the heads are tightened down. The heads themselves are very solid and I do not image they would twist much.I measured the liner protrusion with feeler gauges and a straight edge with the heads off and detected no variation but this did not appear to be the case when the engine was assembled. I do not recall what brand gaskets were used as it was a very old set that came with the car. All has been good for 6000KM so far.

Best of luck.

Michael

[rogermark]

Thanks, Michael for your input

I re-checked various points of interest while I wait for the new head gaskets

I did find that the liner protrusion is between 3 and 5 thousands of an inch in various places. The book says it should be between 1.5 and 2.5 thou.
I did put a smear of non hardening sealer on the liner gasket faces after cleaning the liners and seats in the blocks

Not sure if this is a major problem

Any experience or comments gratefully appreciated...I don't want to have to take out the liners again..!!

Roger

[LanciaFin]

Hello,

My experience is, that this kind of leak is "normal" with the modern gasket material. My gaskets, from Emporio Ricambi as well, had this problem too. Initially it was very bad, I had to place a bucket under the right side head, the leak was so severe. The engine had been over 1 1/2 years sitting unused after putting together. On left side head there was also a smaller leak. I retightened the head bolts, and the leak on the left stopped, but on the right side only diminished. After checking for cracks (leak detecting spray and little air pressure in the cooling system) and waiting for two days I retightened the bolts again, and finally the leak stopped (there may be some very minor "sweating" still, but I won't do anything until the engine has been in use some time.) The head gasket seems to compress over time more than the originals did, so the bolt tightening sequence defined by Lancia does not work as easily. After the leak had stopped, the valve clearances had lost over 0.10 mm.::o

In my case, both the heads and crank cases had been skimmed to very good quality surface, and bolts and threads throughly cleaned. Should I need to take the heads out some time, I'll use VHT Copper Gasket in installation of new gaskets.

Regards,
-Miika