318 balancer on a 360 crank advice needed

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str12-340

str12-340

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Please pay no attention to the balance issues that are inherent here. I am trying to mock up some pulleys and spacers to solve a custom accessory issue on a car that is 3000 miles away that has a 318, so I was going to use an engine that a friend has on a stand. The engine is a externally balanced 360 and all the stuff I was using for the mock up is from an internally balanced 318. When I put the 318 balancer on the 360 and tightened it up it doesn't seem to want to get as close to the timing cover as needed. It seems about a quarter inch off and that won't work because then the crank pulley would not be in the proper location. Is the 'snout' of the crank on a 360 longer or somehow different than on a 318 crank???
 
360 Balancer, of course they are going to be different.

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str12-340 said:
Please pay no attention to the balance issues that are inherent here. I am trying to mock up some pulleys and spacers to solve a custom accessory issue on a car that is 3000 miles away that has a 318, so I was going to use an engine that a friend has on a stand. The engine is a externally balanced 360 and all the stuff I was using for the mock up is from an internally balanced 318. When I put the 318 balancer on the 360 and tightened it up it doesn't seem to want to get as close to the timing cover as needed. It seems about a quarter inch off and that won't work because then the crank pulley would not be in the proper location. Is the 'snout' of the crank on a 360 longer or somehow different than on a 318 crank???
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Not to my knowledge, no. Since I have KNOWN of actual cases where people installed the wrong balancer on both 318s and 360s I am almost 100% certain that they will interchange physically. Now, what I AM unfamiliar with is the early setup to the late. The early setup used different timing covers and water pumps, so I am unsure about the balancer's physical interchangeability with the early stuff, but I think they will physically fit, too. Let me ask you this. Are you 100% SURE what you have is a 318 LA balancer?
 
yes, sure it's a 318 balancer (I don't own anything that is externally balanced). This should mean that installed on a 360 with a 1970 318 timing cover and balancer, the distance to the timing marks on the cover should be the same as a 318 and therefore the face of the balancer where the crank pulley mounts should be correct for our mock up if I can get it to pull up in place)?
 
str12-340 said:
yes, sure it's a 318 balancer (I don't own anything that is externally balanced). This should mean that installed on a 360 with a 1970 318 timing cover and balancer, the distance to the timing marks on the cover should be the same as a 318 and therefore the face of the balancer where the crank pulley mounts should be correct for our mock up if I can get it to pull up in place)?
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I would certainly think so. You say in your first post that it's being held off like 1/4". Is that right? .....and what do you have to compare to? Now, I have seen where some balancers are larger in diameter and actually hit the timing mark on the timing cover and that stops it from installing all the way.
 
might want to pull the balancer back off , make sure that the keyway didn’t go catty wompis on you , stopping the balancer from going on all the way !
 
RustyRatRod said:
and what do you have to compare to?
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I have a different 318 that is complete and running in a car. The balancer is quite close to the timing marks cast in the cover, but when I installed this it sets a bit more than 1/4 inch from the marks
 
I'll pull it back off today and see if there is an obvious problem, I just didn't want to keep fiddling with it if this was a square peg in round hole issue.
 
str12-340 said:
I have a different 318 that is complete and running in a car. The balancer is quite close to the timing marks cast in the cover, but when I installed this it sets a bit more than 1/4 inch from the marks
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Ok and have you compared it to haw far back another balancer sits, or are you just "feeling like" it doesn't go back far enough? I'm sorry I don't have any small blocks to compare to. The closest thing I have is my 331 Hemi which does have a small block balancer (340) but it has a custom timing cover. I don't think comparing to that would do you any good.
 
This is a difference that is easily discerned by the naked eye, and when measured is about 1/4 inch which, if wrong, would throw off all of my efforts to figure out spacers for excellent belt allignment
 
Just throwing a thought in here, but have you measured the distance from the pulley mounting surface to the inside flat surface of the hub that the seal rides on and the keyway groove is cut into. See if the 318 and 360 are the same distance, then measure to see if the outside rings are the same distance out. On my engine I use the thick 360 damper with the groove machined into it for counter weight, but the ealy 360 used a thin damper with a counter weight. My from the outside of the ring to the flat part with the 6 holes to bolt the pulley on is recessed deeper than the early 360 damper but the pulley still lineup the same. So I guess what I am saying is maybe the ring on your 318 damper is further out on the hub but the pulley mounting surface is the same. Like I said just a thought.
 
Allz I be sayin' is ah um... ida wanna um uh check and er um see if the 318 part would even press on all the way own... emmm-hmmmm....(burp) :lol:
 
Yes the crankshaft damper hub journals on all the LA small blocks crankshafts are the same dimension. Mr Master Mechanic even Uncle Tony know that!
 
19DART66 said:
Yes the crankshaft damper hub journals on all the LA small blocks crankshafts are the same dimension. Mr Master Mechanic even Uncle Tony know that!
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Yes and I'm pretty sure the early Hemi and polys are too.
 
turned out to be a tiny burr on the balancer inside diameter - along the keyway - glad I didn't force it... I think that 19DART66 is correct, at least for all the LA cranks 318, 340, 360

Thank for the help!
 
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