Engine Broke 2.7 Post.

[mepstein]

If you do not trust your mechanic, why are you using him? You will get lots of options on this site on how to build an engine but a good builder isn’t going to change the way they build engines just because you read it on the internet. Did you ever read the engine building books? They will help you understand what and why your builder is doing things the way they do. I’m not trying to be hash. I just know that building an engine “by committee” isn’t a road to success.

[RSTarga]

It is a little silly to do the bottom end and pistons and cylinders and not get new guides and the valve seats redone.
Your index, might as well do it right. In those books you will find a list of parts you will need to replace, quite long. You need to do a budget and wait until you can afford to do it correctly.

[_gonbau]

when I say the complete work on the heads it is the complete work. Seats etc... I'll call tomorrow so they can tell me the job, so far I'm doing the budget for the heads. Changed everything except valves. Springs, guides etc etc... The intention is to wait to have the pieces to carry the heads and do the work, nothing to wait with the stock in a place for pieces to arrive! I think it is the best method. Regarding the mechanic. I trust perfectly. He is quite well known here by people who drive in rallies etc... from my point of view today we offered him money in advance. I reject him because he has a lot of work...that from my point of view speaks to his honesty. So the issue of mistrust with that mechanic is totally ruled out.
Regarding the parts of the cylinder heads, I have budgeted all of the ones on the page except for the valves in the necessary quantities...piezas.jpg

And I don't know where you get that I'm going to make the engine? I think I have always said that I will go to a mechanic if we decide that this engine is the one we keep and for now that is the way. I took the engine to the mechanic today and after looking at it for a while he recommended that. When I have the cylinder heads ready and a crankshaft and he has time, he will take care of it...While it is time to look for the indicated parts and follow the procedure that he indicates to me.
*I am looking for the parts for the 74 2.7S
Another question that occurs to me is if I buy the "pack" of Mahle pistons + cylinders... Obviously the segments are included, etc. assembled? Rossepassion is where I plan to get supplies

[_gonbau]

I have left the cylinder heads at the mechanic. rectify valve seats, guides, align connecting rods! New cylinders and pistons will be purchased after verifying their ovality... the budget for the two heads is approximately 600e. I think it's a good first step for the engine

[RSTarga]

you are only doing 2 heads?

[_gonbau]

sorry, for me the head is the set of 3... let's say that then 6 and 12 valves are being made etc...
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Regarding the crankshaft breakage, according to the mechanic, it seems to be the cause of a bad ignition adjustment. explosion when not playing and subsequent fatigue.

[_gonbau]

I have been researching the engine type and engine numbers for a few weeks now. I hadn't touched or even looked at these prints until quite recently. And I tell you. The engine number appears to be stamped. Not because of the numbers (in the absence of seeing them well) but because of the "pentagons" that I found instead of the stars (I commented on this in another post in this forum)... The curious thing for me is that it coincides with the type of next to. the engine is 614XXX.... the type 911/92 despite the fact that my father believed it was that of an S, I have been able to verify that it is not, since the S 2.7 type was 911/93, correct? Therefore we have here a 150hp 2.7L engine.... The interesting thing here is also the fact that although the engine number coincides with the type in the type there is something else written....... ....... AT. AT I have not found anything. So I have to understand that something happened with this engine** while in Germany? The mechanics have seen that the engine does not seem to have many kilometers...so... Our engine according to stamps is a TYPE 911/92AT.
Something nonsense I guess?
"the at differs from the prints of the type"

[72targa]

A replacement case possibly?

[HughH]

AT stamped on a case means a factory replacement case with the original numbers stamped on it. Probably/possibly rebuilt at the factory given where it originally was and the person who owned it.
Also because it is obviously rebuilt you should be looking at the part numbers for all of the internal parts. Cams, heads, induction components etc to see what they are. It may have been upgraded to S spec when rebuilt and other changes may have been made making it very non stock ( especially given it’s supposed use in Germany) so the cause of the failure may have even been tuning it as a standard engine when it was not

[_gonbau]

as always... a pleasure to read your answers HughH*! I really... thank you very much. I haven't ordered certain things yet although I was planning to do so today. Having seen this... should I wait for the cylinder heads to be disassembled to see what parts they are made of? Very basic question but what is the difference between a 2.7 and a 2.7S? Camshaft? On the other hand your theory Huhg! I'll give you some information to see if it helps you. We have found 1 or 2 pistons with small valve marks. Carbon around time but not in the marks from what I have to understand that the valves were touching "minimally" After an adjustment until breaking since there is no carbon in the "mark" of the piston... I have seen the manual workshop, the difference in valve closure between the 2.7 and 2.7s. Is this the possible cause of our broken motor? What components do I check to see if it is a 2.7s? I was thinking of ordering the pistons and liners today (I think the 2.7 ones don't differ from the 2.7S ones) but just to be sure... I'm sorry I'm such a noob but I really like my doubts to be explained...poor very silly to make me seem.
and thanks72targa! Sometimes my messages are not clear!
I'm going to see if I can take photos of the marks that I mention so that it stays here for posterity.
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If this is still interesting ... I have no problem illustrating with more images and more questions. I've thought about trying to locate the wife of the previous owner of the engine .... but the truth. pff.....