How To Repair Threads On 327 Chevrolet Crank That Holds Harmonic Balancer

Username	Post: 327 Harmonic Balancer and Timing Chain help please (Topic#280489)
warpwr "15th Twelvemonth" Gilded Supporting Member Posts: 960 Loc: Santa Clara, CA Reg: 04-11-06 User Info Transport Private Topic View Profile	05-01-12 03:55 PM - Post#2221263 I took the 56 out for a ride concluding Sunday and went half a block or so and the harmonic balancer cruel right off. I managed to drive the old daughter dorsum into the yard and opened the hood. Information technology didn't shove the fan into the radiator so that was good news at least. I pulled the radiator (and the radiator support, I had planned on removing that Danchuk support anyway because it'south non made correctly, some other story). Anyway, the balancer had popped 1 of the woodruff keys out so there was still one in at that place holding the timing gear. I managed to pull that ane out too with some effort. I pulled the h2o pump and the timing cover and discovered that the timing gear was missing a tooth. Information technology looks similar information technology has been that fashion for a long fourth dimension and unrelated to this problem. Also the balancer itself was missing some of the rubber and the keyway was pushed out of shape. Hither's a movie of the onetime woodruff keys, look how messed up they are. I ordered and take received already (in one twenty-four hour period, standard UPS shipping from Summit Racing) a new ATI balancer, new Cloyes truthful roller timing gear set and new woodruff keys and gaskets for the timing cover and h2o pump. I also noticed that the crankshaft has the beginning of a drilled hole in information technology for tapping and adding a balancer bolt. I can't tell using my old eyes, fifty-fifty with a magnifying glass, if information technology's only partially drilled or if information technology is a broken off drill bit in there. There are no threads so it'due south not a broken bolt. Anyway, I'thou going to effort to continue drilling that hole and tap information technology. I take a couple of questions for the SBC builders out there (I'thousand not one, not all at in one case anyway). Kickoff, the two woodruff keys that got knocked out of the crank are about 3/4 of an inch long 10 v/16 inch tall. The new ones I bought are 1 3/8 inch long x 3/8 tall, about double the size. Which is correct? Are they interchangeable? I mean using simply one in place of the two that came out. 2nd, if I can't drill out that crankshaft volition information technology be ok to go without the balancer bolt? Apparently GM thought so. Third, what the heck caused this failure? Was it the balancer with it's missing rubber or what? Whatsoever ideas? Thanks in advance for your help. Vaughn 56 Delray 327, 5 spd Email Report

Allan In NE Frequent Correspondent Posts: 1990 Reg: 12-27-11 User Info Send Private Topic View Contour	05-01-12 04:34 PM - Post#2221284 In response to warpwr Y'all've got the wrong keys, out of balance dampner caused the dampner to shake and 'walk' foward and yeah, forget the lightheaded bolt; ya don't need it. Allan Lifelong GM automated transmission specialist E-mail Report
Rick_L Member #409 Posts: 27962 Loc: Katy, Tx, United states of america Reg: 07-06-00 User Info Send Private Topic View Profile	05-01-12 05:42 PM - Post#2221312 In response to warpwr Your old balancer is the earliest version they made. I don't know what yr they switched (maybe 64?), just afterward that the rivets were gone and to me the balancer and pulleys are much better. You will probably have to supplant the crank pulley as well, with a 64-up (or any the yr is) bolt on pulley. I don't think the keys you have will work, you lot'll have to find some shorter ones. Any car supply should exist able to help you there. I think you've described the pigsty in the crankshaft correctly, it'southward either not deep enough or there is a broken drill fleck in there. Just the "special high performance" 327s with 8" balancers had a commodities there. Never a 283. You don't actually need that bolt unless yous are turning a lot of rpm (say over 5500). I don't know what ATI damper you bought. If information technology's viii", yous'll need to cut and grind some notches in your front motor mountain brackets if you're still running those. Email Study
62chevy427 "15th Year" Silver Supporting Member Posts: 2213 Loc: laurens sc Reg: 04-xiii-06 User Info Send Private Topic View Profile	05-01-12 06:52 PM - Mail service#2221351 In response to warpwr if your creepo has ii places cutting for woodruff keys,you will demand two keys like the ones y'all took out. earlier installing the new balancer ot the new timing gear,check the fit of the woodruff keys. they should have to be tapped in. no play whatsoever. if at that place is play, sometimes making raised spots on the side of the keys with a eye dial works. the balancer also nedds to accept a pressfit, brand sure your crank is not worn. i ever drill and tap the hole in the crank,just for insurance and for installing the balancer without having to use a hammer. 56 bel air ((since 2002) 62 impala ss (since 1965) 65 el camino (since 1969) 66 nova (since 1987) 67 malibu convertible (since 1981) 72 el camino ss454 (since 1985) 83 gmc 4wd (since 1991) 95 impala (new) fifteen chevy equinox Email Written report
models916 Valued Contributor Posts: 4785 Age: 70 Loc: Addison, IL Reg: 05-28-10 User Info Send Individual Topic View Profile	05-02-12 08:19 AM - Post#2221533 In response to 62chevy427 Those look similar offset keys used to dial in a cam timing issue. Maybe I am non seeing them conspicuously? Email Report
warpwr "15th Year" Gold Supporting Member Posts: 960 Loc: Santa Clara, CA Reg: 04-eleven-06 User Info Transport Private Topic View Profile	05-02-12 08:57 AM - Post#2221551 In response to models916 I had ordered the wrong keys, I bought GM "long" ones. I will become the correct ones. Rick, the new balancer is an ATI 917781, vi.37 so no problem there. I will try to drill the crank but if information technology's a chip stuck in there I think I'one thousand out of luck so I'll just do without if that'south the example. Information technology would help to pull on the new stuff though. I have a two groove bolt on pulley and it'southward the one I had put on originally, it looks fine. The erstwhile keys do kinda look like they're starting time simply only whacked out of shape on closer inspection. So, thanks for all the reply'southward guys. I'll be back if (when) I run across whatsoever more surprises. Vaughn 56 Delray 327, five spd Email Report
rj_ly Honored Member Posts: 17575 Loc: Southwestern OH Reg: eleven-fifteen-02 User Info Send Individual Topic View Profile	05-02-12 11:06 AM - Mail#2221600 In response to warpwr Any balancer I've e'er seen only had one key to hold information technology in place. I fundamental for the balancer. One primal for the creepo timing gear. My '68 327 does take a drilled & threaded hole in the eye. But I bought the engine straight out of a '68 Biscayne and it never had a bolt in the end of the crank that I ever saw? STill, I installed one two years ago when I painted the engine. 57 Hrdtp(mine for 40 YEARS JULY 12) 57 210 4-dr Sdn(37 yrs Aug 12) 57 Hrdtp(32 yrs Jan 12) 57(windowed)S. Delivery(31 yrs Oct 12) 57 150 Wgn(24 yrs Mar 12) 57 210 ii-dr Sdn(8 yrs Oct 12) Edited by rj_ly on 05-02-12 11:07 AM. Reason for edit: No reason given. Email Report
Rick_L Fellow member #409 Posts: 27962 Loc: Katy, Tx, U.s. Reg: 07-06-00 User Info Send Private Topic View Profile	05-02-12 03:48 PM - Postal service#2221677 In response to rj_ly I've had one 283 crank that had 1 long key that located both the timing gear and the balancer. E-mail Report
models916 Valued Correspondent Posts: 4785 Age: seventy Loc: Addison, IL Reg: 05-28-10 User Info Send Private Topic View Contour	05-03-12 04:51 AM - Postal service#2221877 In response to warpwr You will need a new timing pointer for the ATI. Information technology will exist ten degrees different from your stock damper. In 1968 Chevrolet relocated the TDC mark on the dampers. New bolt on mark will correct the departure. Email Report
triplefive Contributor Posts: 700 Loc: Brisbane Commonwealth of australia Reg: 07-08-eleven User Info Send Private Topic View Profile	05-03-12 11:32 PM - Post#2222255 In response to models916 Another recent thread along similar lines that you lot might not have seen is here: https://www.chevytalk.org/fusionbb/showtopic.php?ti... Mike. Procrastination; the one thing I never put off until tomorrow. Email Study
warpwr "15th Year" Gold Supporting Member Posts: 960 Loc: Santa Clara, CA Reg: 04-eleven-06 User Info Send Private Topic View Contour	05-28-12 12:l PM - Post#2230815 In response to triplefive It turned out that I needed to use the ane long key after all. I managed to drill out the crank using a copy of an invention by cla55ic invention (aka Lloyd) to keep the drill bit lined upwardly with the eye line. Drilled direct into the crank about 2 i/2 inches from the front edge of the creepo. Information technology went a lot easier than I thought it would, there was no broken off drill fleck or bolt in there, apparently someone had started to drill information technology out before and given up. And so I tapped the pigsty 7/16-xx. Next came a new Cloyes timing gear and chain since the sometime i had a tooth missing. The new Felpro prophylactic timing cover to pan seal went on without much struggle, it wasn't as thick as the ane that came out so I put a layer or Black RTV on it first and then around the bottom of the comprehend as well. Hope she doesn't leak. I pulled the new balancer on with an installation tool and put an ARP balancer bolt and washer on with thread locker. Had my GM radiator support blasted and powder coated and installed it forth with the radiator and hoses. Filled it up with coolant and she fired right up. Runs a fleck smoother than information technology did with that messed upward one-time balancer, seems like. Mission accomplished so THANKS again to all who helped me out here. Today might be a great solar day to finish taking that ride... Vaughn 56 Delray 327, v spd Email Report
56sedandelivery Deceased Member RIP Posts: 5917 Age: 70 Loc: Everett, Wa. Reg: 02-26-08 User Info Ship Private Topic View Profile	05-28-12 03:32 PM - Mail service#2230864 In response to warpwr You practise know there are TWO different forepart pan to timing instance gaskets; a thick and a thin 1? It depends on the year pan being used which gasket goes on. Commonly, there are both gaskets in an overhaul or timing set. I've got my fingers crossed for you. Butch/56sedandelivery. Email Report
warpwr "15th Twelvemonth" Aureate Supporting Member Posts: 960 Loc: Santa Clara, CA Reg: 04-11-06 User Info Send Private Topic View Contour	10-fifteen-12 09:51 PM - Post#2280126 In response to 56sedandelivery 56sedandelivery Said: You do know there are Two dissimilar front pan to timing case gaskets; a thick and a thin ane? It depends on the year pan being used which gasket goes on. Usually, there are both gaskets in an overhaul or timing gear up. I've got my fingers crossed for you. Butch/56sedandelivery. The forepart seal leaked a scrap. I knew it went dorsum together besides easy, nothing works out that unproblematic. I pulled the pan and measured... (55-74 sbc's used the thin seal (felpro 34509t) and 75-85 used the thick front seal (34510t). If you're not sure what you've got, lay a directly edge across the front oil pan rails and measure downwards to the pan seal lip. 2 1/4" uses a sparse seal and 2 3/8 uses a thick seal)...this from another forum that I Googled... ...and then fifty-fifty though it's a '67 motor information technology does accept the pan requiring the thicker front seal for any reason. Anyway, information technology'southward all back together now, again, and leak free this time I hope. Maybe this info will help someone else in the hereafter. Vaughn 56 Delray 327, 5 spd Email Study