Hi Mario, glad to meet you here and that you actually signed up after our nice 'conference' this afternoon. I hope, the questions will come. Of course I have immediately documented your recommendations about liner protrusion adjustments and block/head tolerances in my WSMs for a future engine rebuild. And noted all the other interesting insights. Since you told me, that you regularly visit Ferrari UK (Maranello Concessionaires), GTO Engineering in the UK, regarding gasket topics as well as the factory jn Maranello; Are you responsible for the gasket supply for the Maranello based Classiche department too? Best Regards Martin
Mario Welcome to the board. What recommendation do you have for the "liner protrusion" issue with regard to the use of Elring head gasket?
Hello all, THX for the warm welcome. I want to introduce myself in a short way, so that you have an idea about my Ferrari activities for Elring. I´m with Elring Aftermarket since 2001 as a Technical Trainer. Meanwhile I´m Director Technical Marketing (do not understand wrong) and responsible for a lot of technical issues and the technical communication for our Division. In deed I travel UK regularly and visit some engine rebuilder there, some on regularly base, but at Maranello I was just twice and at GTO just for one visit - to avoid misunderstandings. I have been in Maranello / Italy to discuss one topic and had some internal mail-traffic with my Elring colleague in UK the engineers in Italy. Due to the fact that I´m not in response for the Sales, I have to clarify the question whether the Ferrari Classic Center is our customer. My contact mostly is our Business Unit in UK, Elring Parts, they have a good customer base for the "red brand". I´m on a business trip in NL in the moment followed by a journey to UA. During the travels I will read the tread in detail and comment all the discussed facts. To start the conversation, you asked for the topic "liner protrusion" - this is difficult to explain in short words, I will come back later. Basicly, we should think about all the engine families and types, old 12 cylinder, newer 8 cylinder, etc. - if we talk about CHG in general, we have to have in mind that we talk about gasket development from the 60th, 70th and 80th. Material changed several times, you all know the asbestos topic in the 90th (from Elring view) which is very popular, but through the decades there have been more significant material changes. Our topic are the "Metal-Soft-Material" CHG, made of a perforated steel carrier with rolled-on soft material and mostly some silicone screenprint in addition. The soft material was always based on cellulose with a kind of stabilizer and additional bond inside. These recipes changed from time to time due to different reasons like raw material availability and prices, environmental and worker protection laws and simply the fact that decade old material production machines has been shut down. NOT part of the discussion are so called "MLS" versions, multi layer steel gaskets of today, established since beginning of the 90th, depending on development. Of course a gasket manufacturer and an engine manufacturer are always in close contact for development and changes. That means the material specs like temperature and chemical resistance or material settlement for example, are nearly equal in comparing the different materials. Nevertheless, the CHG periphery is more important like before, because sometimes the tolerances of the replaced materials are slightly different. In fact of this clamp forces and the technical specs like part distorsion, surface roughness, thread quality, bolt or stud condition must be perfect, otherwise problems can occur and affect the complete system - in some case. Give me a chance to read the post history first, but I suspect "CHG not fluid tight (oil / coolant) after tightening" - to solve this problem you have to create a higher backland or periphery pressure. How and what to take care I will post soon, but it´s obviously - you can influece this by adjustments of the liner protrusion... I know, general and basic Know-How so far, but I will go more in detail with my next post. All the best Mario
Hi John, something went wrong with your quote Regarding liner protrusion, with those modern gasket materials it's recommended to approach the lower limit of the tolerances one can find in the WSM for the 2V-engines and even go slightly below for the 4V-engines. The voodoo priests may disagree. Best from Germany Martin
When ever I do a head gasket job, no matter the car, I allow a rest period between torques. I will set an initial torque of say 20nm..rest, then 40 nm, rest, then set factory initial torque, rest again. I call it crush time. I then work my way up to the factory spec in stages in 20nm increments. If the spec requires degrees, I split the number in half. If 90 is final, I will torque all at 45, rest, then another 45. Never had a leak yet. Process is just as important as torque. Time consuming for sure..and I hate it.
Hello all, Sunday - some time to give more facts… Generally - the production plants for Ferrari CHG in the "Elring World" Gasket production is global business. ElringKlinger as the concern and Elring as the IAM brand have in total more then 50 plants around the world - reason is clear, wherever engines and cars are produces, the supplier of spare parts should be near. As a matter of this our plant in Brazil delivers to VW do Brazil, our plant in China to VW in China and so on. Ferrari gaskets are treated different because of the quantity. The MLS CHG of today we deliver to Ferrari from our HQ in Dettingen / Germany as so called "small series" production - this we do in our prototyping department. Not so the "old" metal-soft material CHG! In that case some honest words are necessary - for all of you the Ferrari you own is a kind of treasure, for us it´s a car and we have to calculate like all the others. We have to answer questions like profitability, labour costs, factory costs, turnover and much more - short a business case calculation. As a matter of this we made the decission to stop the production of the soft-material in Germany and we scrapped the production machine in our HQ to use the space for development of alternative and future solutions. The HQ is development Center for future High-Tech and production line for actual High-End CHG. ALL the metal-soft material CHG and periphery gaskets has been sourced out to our European Business Unit plants. This can be the plants in Spain, France, Italy and UK. They all source the same material. The question which gasket comes from where has to be answered on reference base, it depends where the toolings went trough. Not all Ferrari IAM gaskets are coming from just one plant. Summary - yes, in comparison with elder gaskets (used or new), the actual parts coming from our stock might look different (material) and can have a different country of origin. But all are original and the functionality is guaranteed. Technics - Liner Protrusion The CHG we are talking about are made of metal-soft material as explained before. This material is pressed to the surfaces of Cylinder-Head (simply - head) and Engine-Crankcase (simply - block) on the full gasket body. We are talking about a full surface contact. This is completely different to the todays CHG with a so called "line contact" along a flexible bead. The old CHG generation was a static material plate in a full dynamic system, the dynamic comes from the vibrations of the sealing gap in a range of 2 - 10µm. This sound like nothing, but has an incredible influence of CHGs function and the durability. The most critical fact are the setting rates, the decrease of gasket thickness during the engine life cycle and caused by this the loss of clamp forces of the bolts or studs. With the liner protrusion - we make a difference in between dry slipped or pressed liners and wet liners - you have a significant influence on the pressure in the system and on the gap-vibrations as well. In case the engine reconditioner sets a liner protrusion on the max., more clamp force is necessary to torque down the gasket correctly. To torque the gasket down to the best possible full contact pressure, to make sure that pressure force is perfect around the combustion bore and, also important, in the gasket periphery, the gasket backland around coolant channels and oil bores. As more line protrusion you have, as more pressure you have around the combustion fire ring, the so called "eyelet", but as less pressure you have in the backlands. If you remember the material changes, now - it should be understandable that there are some smaller changes because of different material tolerances. We as a gasket producer can guarantee that the gasket will work 100% if all necessary requirements are fulfilled - so we need the flat surfaces (Distorsion max 0,05mm in lenght / 0,03mm in width), we need the correct roughness (Rz 20µm, Rmax 25µm, no flat areas _____/\____/\_____ - we need exactly defined peaks /\/\/\/\/\/\/\/\/\/\ ) which means no grinding paper allowed on aluminium. Be strict to yourself, sometimes we saw corrosion, this must be removed. We recommend to replace stretch bolts (tightened with angles), standard bolts (tightened with torques) and studs can be re-used according the Ferrari specs. In case of wet liners the liner protrusion must be equal from liner to liner and along one liner flange as well - tolerances are important. Last not least - the clamp forces… Technics - Clamp Forces Mostly we are talking about aluminium blocks without tie-anchor for the bolts. Both views of the technics are similar, doesn´t matter whether bolt or stud - from the view of clamp energy and the transmission of pressure power. Have in mind, that this transmission is completely different in grey casted iron blocks and aluminium blocks without tie-anchor. The thread of the bolt / stud and the thread of the bore hole doesn´t fit 100% - contact is on smaller areas first. The addition of all this single areas gives the total area to transmit the bolt power in NM/mm2. Threads in grey casted iron are strong enough for this transmission - the alloy threads sometimes not. As a matter of this the bolt power will cause a smaller deformation of the thread flanges in the engine housing until there is enough contact to transmit the bolt power. As a matter of this threads in aluminium housings get weak after some usages and get bigger deformation, simple words the flanges are bent to above until the bolt pulls out the thread. Re-cutting of alloy threads is NOT recommended! This meets exactly what tbakowsky mentioned - sometimes it´s necessary to give the bolt / stud - crankcase screw joint a relaxation time. This can bring even better results… Summary Technics If you combine all these facts - you will easily understand that the conditions of surfaces and the influence of the engine periphery is essential, especially after all that changes in the past. If really anything is ok, then the gasket works with the recommended liner protrusion - if the clamp forces are as recommended as well. If you meet any problems with leakages, especially a loss of fluids after torqueing down the head (shortly after repairing) you can solve the problem with a reduction of the liner protrusion. In doing so, you reduce the pressure along the eyelet, but you can increase the pressure in the backlands. This will definately increase the vibrations of the gap a little - honestly speaking the durability as well - but to solve problems this can be a good recommendation. Normally the Motor Reconditioners know about that fact and they have a lot of experience in finding the correct compromise. Example - on an old 12cyl Ferrari engine we found out that the recommended liner protrusion of 0,09mm is too high to create the perfect gap pressure. Smaller compromises were necessary, because there was worn on the block and a 100% surface work wasn´t to guarantee. So we reduced the liner protrusion down to 0,05mm and the engine is still running. (Just an example - valid just in that case) Why not an official statement? A lot of different gaskets in the shelves of the dealers, all facts based on experience, not valid measures or test-bench runs. In fact no reliable base for an official global statement - the risk to fail is too high. Try to bring the engine in the best possible condition in case of the change of the CHG, then there is nearly no risk of failure. In case there are some compromises to do - check the threads and reduce the liner protrusion carefully - this will bring success in work. In case of any details to ask, feel free to contact me directly. Unfortunately I´m not able to do Forum business every day, so I prefer eMail contact. You can meet me in FB ( Mario Rauch Elring-Trainer ) and use the Messenger or [email protected] Hope you enjoy the offer... All the best Mario
So what I got is: ... there is no global statement that can be made ... ... if there is a leak, reduce the liner protrusion ... ... sneak up on the final torque in steps ... experience counts. OK.
Hello Mario welcome to the chat and a million thanks for the explanation. I would also like to thank FC members who have expressed their opinion on this thread, specially Martin, who invited you to the chat and made this happen. Have to say that me old Elring gaskets did not fail, the block where the heads sit and the heads were warped by 0.15mm both. After shaving block and heads, protrusion was adjusted to 0.05mm (manual states from 0.03mm to 0.07mm...decided to stay in the middle). Using, once again, Elring gaskets(nothing said in this thread convinced me that Elring was a "bad" gasket or was prone to fail). Now comes the torque issue... on one part of the manual it states 4.5 Kg/m + 120 degrees, on another part of the manual it states 10 Kg/m. What did I do? I torqued first to 4.5 Kg/m, waited a couple of days(because the tool broke ) and finished tightening at 10Kg/m. Last week I performed a hydraulic test...filled the block with water a pressurized it to 4Kg /square cm for 20 minutes. The manual says 8 to 10 Kg, but at 4Kg bubbles were coming out of the thermostat housing... don't know how they came up with that figure??? End result...Not one drop of water leaked from the gaskets, inside (cylinders) nor outside. Also to say that the o rings between the liners and the block didn't leak either. Did not replace the studs to 11mm as recommended by someone on this tread, stayed standard 10mm. When I start it up, may or may not hold, I'm pretty confident that it will...more to come. Thanks and best from Spain. John.
Hi John, disable it. I disable all those disputable "additional useful features" on all of my devices. Those just bother me. I was at school once. That's sufficient for my needs Best from Germany Martin
Hi Robert, let me try to explain the reason based on german habits. If you disseminate a written bulletin here and something goes wrong, the mechanic will blame the bulletin author -supplier here- for it. Even, when he did a hack job, first thing is trying to blame others for it. The courts are overly busy with such BS. (this contains parts of sarcasm, and parts of truth ) Best from Germany Martin
Totally understand but still unacceptable. How many countless hours and dollars spent until this is found out? Proper explanations go a long way like what we just got.
Yup!!! Totally agree!!! If we went to school to learn how to read and write, why would we need correctors? I'm not against technology, but some times it makes me feel dumb. Like if I needed a corrector to write my name...for heaven's sake! John.
I've been following this thread with some interest as I'm currently reassembling my own engine (308 QV) and of special interest is the subject of liner protrusion. For one thing the 308QV/328 Workshop Manual shows a value of .03 to .05 in the drawing (Fig 3 on page B3) and then .03 to .07 in the table on the next page (B4). I have accepted this as just another example of a number of errors or conflicting data in the WSM, it's not a perfect document. But regardless, in following this discussion I'm left wondering how one would go about "adjusting" the protrusion if one found it to be out of spec? For reference the allowable range is .04 mm and a standard sheet of paper is .11 mm or nearly three times as thick. In my case all of my liners measured .002" which equals .05 mm so I'm not faced with this dilemma but since it's being mentioned here I'm curious as to how it would be done. These are very close machine tolerances and it would seem the only thing that could be altered might be the liner base o-ring which doesn't seem like a very accurate method of achieving this.
Cometic are not composite they are MLS gaskets (Multi Layer Steel) I researched this and asked around, you cannot (or should not) use MLS gaskets with protruding liners.
Has this ever been done? My assumption on liner protrusion check is that it could possibly be under if the base 0-ring were damaged but how could it be over unless an error was made during manufacture? Seems unlikely. Regardless, we are talking about a range barely over one thousandth's of an inch. This is very minute.
