Harmonic balancer are all external balanced all the same?

[71monacomoparmechanic]

Im putting a new harmonic balancer on my engine. It's originally a 71 dodge 383 2bbl
so I think it's externally balanced engine.
It currently has a balancer off a 77 chrysler 400 4bbl engine which should be external too. First are all those extetnal balancers weighted the same. My engine seems to vibrate too much. Second I'm putting a cam in it and want to replace the balancer while I'm in there and am looking at a professional products 80013 from summit racing that comes with bolt on weight for external balance. Any thoughts or reviews on that. All input much appreciated. Thank you.

 

[4spd300J]

The cast crank balancers were different for each engine. Some of the later ones for cast cranks actually had "use with 400 or 440 cast crank only" on the front. They were usually much thicker than the earlier ones and some had what looked like a crankshaft weight cast on them. Check out this site, it has some info that might help you find the correct one. Harmonic Dampers 440 Source.com

 

[Davea Lux]

Im putting a new harmonic balancer on my engine. It's originally a 71 dodge 383 2bbl
so I think it's externally balanced engine.
It currently has a balancer off a 77 chrysler 400 4bbl engine which should be external too. First are all those extetnal balancers weighted the same. My engine seems to vibrate too much. Second I'm putting a cam in it and want to replace the balancer while I'm in there and am looking at a professional products 80013 from summit racing that comes with bolt on weight for external balance. Any thoughts or reviews on that. All input much appreciated. Thank you.

See www.440source.com/dampers.htm they have a good list of the various dampers. They are not all the same and in '71, the 383 could have either a forged or a cast crank, so you need to be sure of what you have.

Dave

 

[71monacomoparmechanic]

Hey dave. How are you. We spoke about this engine before and determined it is a cast external balanced crank already Engine confusion may need decode

 

[71monacomoparmechanic]

The crank number was 3462923. It's all in that post. I still have the original damper for that engine. Like 300 j said that 400 damper that's on it looks different with that big counter weight on it that looks different from the 71 damper. The question now is should I buy the aftermarket damper, buy a new oem damper or save the money and use the original one I have. The one off the 400 will go. Some people recommend replacing them on old and high mileage cars cause the rubber gets hard or rots so figured I'd do while its off.

 

[Davea Lux]

Hey dave. How are you. We spoke about this engine before and determined it is a cast external balanced crank already Engine confusion may need decode

In that case, the 383 or 400 external balancer will work. Note that the bolt pattern for the lower pulley is different on most of the 400 engines so if you use that balancer you may need to change the lower pulley and that can run into problems because the offset on the pulley is different on the later 400 engines. Check your lower pulley to see if it is an asymmetrical bolt pattern, that is the early style pulley used until '72, if all the bolts are evenly spaced, that is the later style symmetric pulley used in '73 and later, the offset changed about '76. The engine should be properly balanced with the 400 damper, just a matter of finding the correct pulley. Have you checked to be sure you have a weighted torque convertor, that is also part of the external balancing. If the rubber on your existing damper is tight and does not appear to be cracked or rotted, you probably can still use it. I am fine by the way.

Dave

 

[71monacomoparmechanic]

The torque convertor is weighted. I took the 6 bolts off the pully and it's seized on now so I havent pulled the damper yet. I'll have to check the pattern when I get it off. Not sure if I should remove the damper and pulley as a unit if even possible and use a separator or try to air hammer it a little bit. Tried a rubber mallet already. Any tricks? But anyway the cast 383 and 400 are weighted the same then as far as converter and damper?

 

[Davea Lux]

The torque convertor is weighted. I took the 6 bolts off the pully and it's seized on now so I havent pulled the damper yet. I'll have to check the pattern when I get it off. Not sure if I should remove the damper and pulley as a unit if even possible and use a separator or try to air hammer it a little bit. Tried a rubber mallet already. Any tricks? But anyway the cast 383 and 400 are weighted the same then as far as converter and damper?

The pulley will not come off until the retaining bolt for the damper is removed. 383 and 400 use the same convertor. If it is still stuck, spray the hub with some PB Blaster or other penetrating oil and it should come off. Try not to get any on the rubber for the damper.

Dave

 

[71monacomoparmechanic]

Yea I took the damper bolt off as well and sprayed it with rust penetration oil. Still wouldn't pry off or hammer off. Didn't use a lot of force as to not screw up the pulley. Its been soaking for a couple days I'll have to give it another shot when I get back to the job.