I have looked around on here and found most of the info i need. I am putting on a EC 172. I know the torque spec is 148 ft lbs + 90*. My question is, loctite or no? If yes, then red or blue? Thanks in advance.

Eurocharged recommends 275lb-ft + 90* not the oem recommendation of 148+90.

I used red loctite the last time I did it just in case.

^ I have seen people say 275 + 90* but when I asked Adam from EC, he said torque to factory specs.

You asked him recently? I don't know what to say, if he said this recently then go ahead and do so. Jerry told me 275+90 on mine.

275 is waaaaayyyyy to much for the stock bolt. It will lose its authenticity at that level, 148 plus 90* is the correct spec.

It's what EC recommended and it's what I've used when installing my pulley's ( the two times it hasn't fallen off....lol ).

^ I saw your thread where you made your own woodruff key. What is the woodruff key used for on our cars anyway? The EC pulley has no timing marks on it so why did you feel the need to even fix it? Couldn't you have just put where the key would have been at 12:00 and then just line your pulley key way up at 12:00 as well then torque it down?

I am glad my expensive misfortune could serve as entertainment for you bro. Hopefully you come to an event in the US sometime, so you can "LOL" to my face.

Damn that was a low blow

+1. Not sure if that was meant to be a low blow or not but well actually have our pulleys installed correctly to begin with and not really "have" to put woodruff key's in to attempt a fix. Because of our misfortune buying junk crank pulleys we're both out of pocket several thousand dollars and my engine isn't even close to back together.

Well my woodruff key did not completely shear off. It just broke a lil piece. I can still see where the key is but just a lil piece missing. Can I just align the pulley up with the piece of the key that is still there then torque down correctly? Or do I need to put a whole new woodruff in there?

WTF? That wasn't meant as a low blow for you, if you recall my first pulley fell off...I meant it seriously.

Touchy?

My first pulley spun off and damaged my crank snout. The key I made was so that they pulley would not fall off again.

My question is if this is a Mercedes/AMG bolt, brand new, as per their spec, it is 148 fl-lbs + 90*. They know what spec this bolt is built to. Now, if you torque it to 265 ft-lbs +90* you are exceeding the design spec of the bolt. I know that there are bolts built with this capability, but I would think that the grade of hardness of the OEM bolt is set up to yield at the 148+90* spec. It seems logical that the 275 spec will exceed the elastic limits of the bolt and the 90* turn will put the bolt into excessive stretch/failure zone.
If one wants the higher torque figures, then provide a bolt that is of sufficient grade to deal with the increased torque. All this assumes that the crank nose can handle this level of torque. I'm sure EC's research shows that it can. My purchases from EC demonstrates my confidence.

With this uncertainty as to proper torque of the crank bolt I am reluctant to tear into the crank pulley. Perhaps I am timid, but lets go over this again, hopefully with some engineers chiming in. A great man once said:
"Number of times over equals certainty and results."
Jon

Can only comment on my own car. On my 7th pulley without problems (on install anyway) and always 150 plus 90. Big ole breaker bars used to get that 90 too.

Stock to Kleeman to German Pulley to ASP (pulley faulty...welded backwards) to new ASP to EC Aluminum Pulley to final 200mm EC/ASP.

How does the key help to ensure the pulley won't fall off again? I thought the woodruff key was only there to help align the pulley for timing marks. Am I incorrect about that? Does the woodruff key have another purpose?

The woodruff key is there for alignment, and to prevent the pulley from spinning on the crank should the bolt come loose. That bolt was designed for 148+90 specs, sure you can tq it down harder, it can actually be tq down much harder. As you do this, you are stretching the bolt more and more, and it was only designed for a specific amount of stretch before it loses its authenticity.

As for your woodruff key been damaged, get a new one, they are cheap and worth the extra effort. I would also mic and check the runout of yoyr crank snout if you can to make sure it is ok. Let me know if you have any further questions brotha.

Much thanks man & to the rest of you that have chimed in. I appreciate the help and I am not questioning your knowledge, I am just trying to understand this 100%. BUT, if the woodruff key was not intended to bear any load how would it prevent the crank from spinning? If the bolt came loose, and there was a load put on the key, wouldn't the key just break again?

The woodruff key DOES bear some load. It's a small percent, but it is enough the keep the pulley from STARTING to spin off.

^ Ok got it. Thanks again

I saw a crank diagram in one of these pulley threads somewhere but now I cant find it. Anyone have that diagram or know what thread it was in?

Doesn't EC provide a crank bolt with the kit? Is that an OEM bolt or I would think more likely that it is one tha can handle the TQ specs they are providing? Not sure, I better call EC because I have a new 172 kit on they way and am starting to question what it should be tq'ed down to now

It still amazes me how some tuners come up with stuff that differs from the OEM spec for no apparent reason when the OEM spec has had significant resources put into it to derive the values... they arn't just plucked out of the sky and we are not talking small magnitude here its nearly a factor of 2 FFS....

I mean why isnt it 220 or 200 ? Why 265 then ?

Tuner companies know it all attitude sometimes just pi$$es me right off.

While I can agree to a certain extent, the oem pulley doesn't apply the amount of stress to the woodruff key and bolt as the larger pulleys do due to their leverage which kinda nulls the whole argument. How they got the 275+90 number is beyond me...lol

Well for my 168 it was the oem specs and even called Renntech and said the same