Need Help With Flywheel Thread

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blewbyoutobad

blewbyoutobad

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The 3/8-16 thread for the pressure plate pulled out when I was installing a new clutch assy. Can I HeliCoil it. If yes does it have to be balanced afterwards.
Thanks FABO
 
If it were mine? And I had room, I would drill and tap all the pressure plate bolts to the next largest size. I don’t think I would rely on a heli coil here. But that’s not to say that it wouldn’t work.
 
A heli coil would work fine if properly installed, no need to rebalance.
 
TT5.9mag said:
If it were mine? And I had room, I would drill and tap all the pressure plate bolts to the next largest size. I don’t think I would rely on a heli coil here. But that’s not to say that it wouldn’t work.
Click to expand...
The problem with that is there's not enough clearance for the head of the next size up.
 
blewbyoutobad said:
The problem with that is there's not enough clearance for the head of the next size up.
Click to expand...
Helicoil will be fine, no rebalance. But if you do want to go to the next bigger size.... you could use socket head capscrews (automatically grade eight) or specialty bolts with smaller size hexes (aircraft, or bolt specialty houses)
If i were you... helicoil and fly it!
 
The problem with "next largest size" is I don't know if they will fit the pressure plate. Clutch cover -to- flywheel bolts are special. They have an enlarged area, a special "shoulder" which snugs them so to say, into the cover holes and into the tops of the flywheel holes. Do you REALLY want to tap that out to 7/16 and then maybe have to ream one cover hole out, thus creating a "special" clutch cover?
 
67Dart273 said:
The problem with "next largest size" is I don't know if they will fit the pressure plate. Clutch cover -to- flywheel bolts are special. They have an enlarged area, a special "shoulder" which snugs them so to say, into the cover holes and into the tops of the flywheel holes. Do you REALLY want to tap that out to 7/16 and then maybe have to ream one cover hole out, thus creating a "special" clutch cover?
Click to expand...

No way not happening. Going to Heli coil all 6 bolts. The flywheel is 52 years old. Should not be a balance problem if I do all 6. DO NOT want to drill out pressure plate.
 
blewbyoutobad said:
No way not happening. Going to Heli coil all 6 bolts. The flywheel is 52 years old. Should not be a balance problem if I do all 6. DO NOT want to drill out pressure plate.
Click to expand...

What are you doing with this car? Not building a high Reving, more than stock HP output and not hitting the drag strip right? If so, buy a new flywheel. Last thing you want is for this all to come apart. A new Ram Clutch kit with Fly is like 450, way cheaper than a fly through a floor board...
 
blewbyoutobad said:
No way not happening. Going to Heli coil all 6 bolts. The flywheel is 52 years old. Should not be a balance problem if I do all 6. DO NOT want to drill out pressure plate.
Click to expand...
I neglected to add I agree with helicoil. I see no reason however to do all of them unless you suspect they are damaged. No need to do all 6 for "balance."
 
67Dart273 said:
The problem with "next largest size" is I don't know if they will fit the pressure plate. Clutch cover -to- flywheel bolts are special. They have an enlarged area, a special "shoulder" which snugs them so to say, into the cover holes and into the tops of the flywheel holes. Do you REALLY want to tap that out to 7/16 and then maybe have to ream one cover hole out, thus creating a "special" clutch cover?
Click to expand...

I’m not familiar with the 833 flywheels but arn’t the pressure plates doweled to the flywheel? The clutches I am familiar with are. The bolts should not be used in shear on a flywheel IMO.
 
Another thought, how thick is the flywheel? Could you tap the existing 3/8-16 deeper and use a longer bolt?
 
blewbyoutobad said:
No way not happening. Going to Heli coil all 6 bolts. The flywheel is 52 years old. Should not be a balance problem if I do all 6. DO NOT want to drill out pressure plate.
Click to expand...
You don't need to heli-coil all of the holes to prevent a balance problem. Heli-coil the bad hole......there will be no balance problem!
 
TT5.9mag said:
I’m not familiar with the 833 flywheels but arn’t the pressure plates doweled to the flywheel? The clutches I am familiar with are. The bolts should not be used in shear on a flywheel IMO.
Click to expand...
Never seen a factory old school Mopar doweled. Maybe the newer pickups/ diesels are don't know. Ford, GM, Mopar back in the day, the clutch bolts are a special taper deal No dowels

Just a random B&B off Jegs.......

798-414.jpg
 
Mr Gasket bolts. May not be evident, but these are not "standard" bolts/ cap screws. Those shoulders are specifically designed for clutches

M154655455.jpg
 
install lawson keemsert instead. far better over a helicoil. they have thin wall or thick wall serts, they are one piece repair insert.
 
I have a lakewood blowproof BH. I have the car since 1974 and is now just street use, cruising. Im older now and it is such a B to take this stuff apart. That was one of the reasons for the 6 helicoil, although I guess if its going to lose another thread Hopefully it will do it while I am torquing the bolts.
 
Scody21 said:
What are you doing with this car? Not building a high Reving, more than stock HP output and not hitting the drag strip right? If so, buy a new flywheel. Last thing you want is for this all to come apart. A new Ram Clutch kit with Fly is like 450, way cheaper than a fly through a floor board...
Click to expand...
Street cruiser, solid cam, ported X heads. Lakewood BH.
 
I dont run sticks anymore, but if i did, i would want an sfi flywheel. The ram clutches is sfi, is the 440 source?
(I have seen the results of several flywheel explosions, in person. Its not pretty).
 
TT5.9mag said:
Thanks. Same thing I found after looking at brewers site. Seems crazy to me to purposely put the bolts in a shear load but it’s worked for this long so......
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Well FLYWHEEL bolts are under shear load and a much smaller bolt circle. CONVERTER bolts are under shear and there are only 4 and some of them are only 5/16
Flywheel bolts are on a quite large bolt circle, so the torque/ sheer "out there" is much less than nearer the center........
 
33IMP said:
I dont run sticks anymore, but if i did, i would want an sfi flywheel. The ram clutches is sfi, is the 440 source?
(I have seen the results of several flywheel explosions, in person. Its not pretty).
Click to expand...

So is the factory flywheel cast or billet?
 
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