Thread: Replacing the flexplate on a GM ZZ502/502

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so "engine side" means face it towards the tranny right????

if it has a lip on the auto fly this faces the trans engine side faces the engine

LOLOLOLOLOL

Denny and Pat, your suggestion of using the long bolts on the bottom 2 bell housing holes was pure genius. It worked perfectly. I did not even need a tranny jack I just unbolted the crossmember from the chassis and slid the entire thing back. thanks a-lot guys

Here's another pic of one of the bolts. I used 2 really long alternator bolts, and they worked perfectly.

one last question (hopefully), is there anything special I should know about flywheel bolts? Is there a trade secret for removing these things? I cannot get any of them to budge. It's only supposed to by 65lbs of torque, but GM did not read their own manual, either that or they put loc-tite on them. Are they reverse thread by chance? I have spun a socket (6pt) on one already and have tried the Craftsman bolt out kit on one of them with NO LUCK.
Seems every time I think I have this thing licked, it bites back.

Thanks,

John

I was using a 6pt socket and 18" breaker bar. I managed to get 3 of them off, but cannot get the other three to budge. The socket keeps wanting to turn on the bolt head. When I got the other 3 out I did not see any loc-tite on them. I do not want to do any more damage to the bolt heads than has already been done. And, like I said earlier the craftsman bolt out kit is not doing much, I don't think it was designed for this kind of torque.

14mm is what i'm using, 9/16 is the right size I believe but is a little too loose, so I have been using the 14mm, this is the one I used for the 3 bolts that I got out.

okay, I'm off to wal-mart to get a torch. I don't have any 6pt wrenches though. Gonna have to keep using my 6pt socket with a breaker bar. I wish I had a welder so I could just weld a bar onto the head and get it off that way.

yes denny is rigth i think the heads are metric 17mm?they use to be 11/16 and i had a short socket for them. i learned the bolt trick over 20 years ago. dont tell NO one.it is killer

then it 14 mm you do not have to get it that hot to breake the locktite .BE CARE FULL NOT TO SMOKE THE REAR SEALWITH YOUR TORCH OR YOU WILL BE LOOKING AT REAR SEAL TO

Having some problems getting them cherry red, or red at all for that matter. I don't have acetalyne at the house and am using a propane torch designed for sweating pipes. I heated them up a few times, and sprayed them down with some penetrating oil. I do not have, and cannot find a 14mm 6pt wrench, so I am going to try a new type of plier that vise-grip has come out with. The jaws are specially designed to grip hex bolt heads. I'll get back with how well everything worked, or did not.

John

These are those Vise-Grips, anyone have any experience using these? I really don't want to have to get a flywheel bolt machined out of the head if I totallt F**K this one up. I already bought new flexplate bolts so I don't care if I destroy these, I just want to get the damn thing out

John

i can say i have not. but i do not likes the looks of them .they looks to thick ??try to find a six point wrench or try to fine one on line or snap off or mack??i have a 11/16 3/8 drive i used with a breaker bar .six point 14 mm 3/8 drive with a breaker bar ?? try hiting the side of the bolts with a drift punch don t they have a shoulder on them hit them at the base of the bolts if you got them hot the loctite is broke if not try heat them do not cool them heat one at a time look out for the rear main seal

great thanks for all the great tips. The vise-grips were too thick, I could not get a hold of the bolts. I finally said screw it and went for broke. I hammered the Craftsman #8 Bolt-Out onto the bolts and applied even pressure, while pushing the socket onto the bolt at the same time (to ensure it did not slip), well, between the heating, the hammering, the penetrating oil, and the bolt out kit, I finally got the three off. I got enerything reassembled. I am still having problems with the starter though. It will engage, but only cranks once, then I hear the motor going, but the cog on the starter will not spin. I am not sure if I need to shim the starter or not, since this is what caused me to have to replace the flex plate in the first place. I do not want to have to go through this again. according to GM, the starter should not require a shim, since it is a new motor.
Has anyone had problems using the high torque gear reduction starters from Auto-Zone?
Any idea what could cause the starter to engage, spin one revolution, and them just stop spinning the cog, opnce again, I can hear the motor spinning, and the cog stays engaged to the gear ring, but no spinning.

Thanks,

John