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Hey all is there a way to convert 37 foot pounds and final pass at 140 degrees. could I make a mark on the bolt once at say 12 O'clock once its at 37 foot pounds and figure what another 140 degrees would be. This is to install the harmonic balancer. ---------Danfigg
 

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Harmonic dampner is 240 ft lbs. It's nearly impossable to get that 140 degrees with the engine in the car.
 

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Hey all is there a way to convert 37 foot pounds and final pass at 140 degrees. could I make a mark on the bolt once at say 12 O'clock once its at 37 foot pounds and figure what another 140 degrees would be. This is to install the harmonic balancer. ---------Danfigg
If that's the torque spec, (140 degrees past 37 ft/lbs) sounds odd but don't mark the bolt. Instead, after you hit 37 ft/lbs make a mark that corresponds to one point of the 6 point bolt hex... rotation of each flat past that mark equals 60 degrees, so your going to go almost 2 1/2 flats (2 points and almost mid way to the 3rd point) for 140 degrees.
 

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This method seems flawed to me. They say this is more accurate than
a torque setting, BUT their starting point is a TORQUE SETTING???

Larry
 

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This method seems flawed to me. They say this is more accurate than
a torque setting, BUT their starting point is a TORQUE SETTING???

Larry
:confused

GM does this with all the TTY bolts. I bought a torque angle meter and haven't used it once. I use Rukee's methed when I torque them. I'm not sure if the torque setting seats the bolt then the addentional degrees is the one the sets the bolt and calculates for bolt stretch.
 

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Discussion Starter #9
re

Yes I have a new GM bolt and no its not 240 ft pounds. But that is strange that You can't reuse the old bolt but you can use the old bolt to seat the New balancer and torque it to 240 ft pounds to assure its seated properly. The reason I thought of using 12 oclock as the spot for a mark on the bolt would be to make it easier to judge 140 degrees from the 12 o clock position. So I think you would actually have to mark the socket at 12 oclock so you can see the movement and make a mark somewhere to show where you have to stop.Rukee sounds like you got it so I will go with your method. Even if I went a little more than 140 degrees the fact that the old bolt is torqued to 240 ft pounds to seat the balancer in the first place, I dont see any harm if im off a few degrees.---danfigg
 

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I used 240ft lbs on the old and new bolt. I think I've done this before. And yes I have the service manual. The balancer is pressed fit without a keyway, have you seen damage a balancer would do if it comes off, I have. I also have mine pinned to the crank something that GM should have done.
 

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Angle is far superior to a simple torque spec. Torque is based on friction in the system. Every bolt and thread are different and thus, friction is different. Angle relates directly to thread pitch. By turning a bolt X amount of degrees, it guarantees that X amount of displacement in the vertical direction which ultimately creates clamp load which is what you want. Torque is an indirect way of achieving clamp load. Half the reason they give an initial torque spec is - can you imagine the backlash from service departments when you tell them to hand tighten the bolt and then go X amount of degrees. They would pee themselves...hand tight? I actually design a torque spec on a commercial diesel engine fuel system called out as HT+120. aka...hand tight plus 120 degrees. Everyone freaked out...until you explain....
 

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Although this tread is starting to sound heated, I find it educational and I hope others are paying attention. It is not as easy as say a small block chevy to change to balancer. This LS2 is serious business. I will repeat the directions so everyone gets a clear understanding of what going on here. The LS2 balancer is a pressed on fit. The directions say put it in an oven for 15 mins then put it on (lining it up of course). Heating it will allow it to slide on easier when torqued into place and when it cools down it will be a pressed fit. I think if you dont heat it and just press it on it will not duplicate the pressed fit process that is required for this type of balancer. I dont think I would want to remove the balancer more than a few times. I would imagine that material is being removed from the crank snout ever time its removed which would create a loose fitting balancer and evenually the wobble and spin on the crank since there is no key way such as the small block chevy. GM4life states he also "pinned" his balancer on which sounds like a good idea to prevent the balancer from spinning in the crank (why is there no keyway on this crank). What ever case then the torque spec is equally important. The explanation Stealthy4 gave is an eye opener thanks all---------Danfigg
 

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Although this tread is starting to sound heated, I find it educational and I hope others are paying attention. It is not as easy as say a small block chevy to change to balancer. This LS2 is serious business. I will repeat the directions so everyone gets a clear understanding of what going on here. The LS2 balancer is a pressed on fit. The directions say put it in an oven for 15 mins then put it on (lining it up of course). Heating it will allow it to slide on easier when torqued into place and when it cools down it will be a pressed fit. I think if you dont heat it and just press it on it will not duplicate the pressed fit process that is required for this type of balancer. I dont think I would want to remove the balancer more than a few times. I would imagine that material is being removed from the crank snout ever time its removed which would create a loose fitting balancer and evenually the wobble and spin on the crank since there is no key way such as the small block chevy. GM4life states he also "pinned" his balancer on which sounds like a good idea to prevent the balancer from spinning in the crank (why is there no keyway on this crank). What ever case then the torque spec is equally important. The explanation Stealthy4 gave is an eye opener thanks all---------Danfigg
The thread it not getting heated. There are very few people on this forum that has had hands on experiance with the LSx motors. I'm sharing my experiances and from what I've heard from others. Its not that easy to slap on the bolt and get 140 degreese hince my first post in the thread. Hell it was hard enough to get 240 ft lbs. Didn't say it can't be done. I've heard some people broken the bolt tring to get to 140 degrees. Some folks use a ARP bolt insted of the stock TTY bolt.

Heating is a common practice to use when press fitting anything that is metalic. You do the same thing when installing press fit pistion to connecting rods. When it cools the metal contrats and it is pressed fit. I guess GM decided to save a few pennies just not to key the crank. They only key the crank on the LSA and LS9 engines. Press on the crank pulley as much as you can without using the bolt, you don't want to srip out the treads in the crank.
 
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