Balancer bolt holes dont line up with factory pulley holes

[Garrick 1959]

Ordered a new harmonic balancer 'PRW' brand, all the bolt holes seem to be 1 3/8" on center the factory balancer has one set of holes at 1 1/2" on center... why i dont know ive tried clocking it all the way around gets worse or better but one hole never lines up. On the new one.
Ive seen the offset holes on flywheels and flex plates. Had to turn them till all holes lined up.
Trying to find a balancer that is made correctly any input appreciated.
Had to replace timing cover and water pump thought id put a new balancer on since the old one already has a repair sleeve on it.
See picture

 

[Kern Dog]

There was a short time where ONE bolt hole was offset from the others.
It looks like you have one of those. Just file the hole oversize and move forward with it.

 

[TN Mopar]

There was a short time where ONE bolt hole was offset from the others.
It looks like you have one of those. Just file the hole oversize and move forward with it.

This is exactly what I had to do

 

[Vaanth]

Ordered a new harmonic balancer 'PRW' brand, all the bolt holes seem to be 1 3/8" on center the factory balancer has one set of holes at 1 1/2" on center... why i dont know ive tried clocking it all the way around gets worse or better but one hole never lines up. On the new one.
Ive seen the offset holes on flywheels and flex plates. Had to turn them till all holes lined up.
Trying to find a balancer that is made correctly any input appreciated.
Had to replace timing cover and water pump thought id put a new balancer on since the old one already has a repair sleeve on it.
See picture

View attachment 1981550

View attachment 1981551

1964 - 1971 harmonic balancers and the lower pulley have an asymmetric pulley bolt pattern with one bolt offset (except the 361 and 413 heavy truck engines). This was changed in 1972 to be symmetric. As advised, elongating the bolt hole allows use of that last bolt hole on the pulley and balancer.

 

[1 Wild R/T]

71 and earlier have the asymetrical pattern... elongate the hole

 

[MoparLeo]

Welcome Wagon
Introduce you self and car if any to the Welcome wagon.
What are you working on ?
I ran into the same problem trying to use 318 pulleys on a 340 engine..

 

[pnora]

Ordered a new harmonic balancer 'PRW' brand, all the bolt holes seem to be 1 3/8" on center the factory balancer has one set of holes at 1 1/2" on center... why i dont know ive tried clocking it all the way around gets worse or better but one hole never lines up. On the new one.
Ive seen the offset holes on flywheels and flex plates. Had to turn them till all holes lined up.
Trying to find a balancer that is made correctly any input appreciated.
Had to replace timing cover and water pump thought id put a new balancer on since the old one already has a repair sleeve on it.
See picture

View attachment 1981550

View attachment 1981551

What engine? Internal or external balance? You need to know that or else you could be installing the wrong balancer.

 

[BeepBeepRR]

Assuming you have rotated the pulley 360 degrees checking hole alignment? I have installed a factory pulley and it only went on one way. Check that there isn't one particular way they line up.

 

[RemCharger]

If my eyeballs aren't lying to me,, I'd say we're looking at an old poly with the weird setup. Where's the new rubber bonded part?

 

[Garrick 1959]

To everyone,
Thank you for your input and suggestions, what a great group of folks!
It looks like the consensus is, Chrysler/Dodge did the asymmetric hole thing on the original damper and the pulley. Not sure if an actual Mopar balancer is even made anymore. Classic Industries has one for $516 (out of stock) and don't know if holes are asymmetric on that one. So looks like I'll set up the pulley on my X Y table on the drill press with a rotary cutter bit and elongate the hole for the new balancer, is the best value to keep her on the road. This car will never be a Concours type show car. She's nice but I like to drive her and not just look at her. ;)
I have attached a picture of what started this whole journey. Along with prep for new TC. Went to move the car out of my shop for another project she sprung a leak... Notice the top bolt boss is almost gone and the groove to the left of the boss I did with my finger nail... New timing cover fixes that. At the bottom of the picture is the factory damper and pulley... Not sure if the correct coolant was used in it. Certainly will flush and put the correct in to help the new cover not corrode. Not sure by the time the new one does Ill need to worry about it. ;)

 

[33 IMP]

Everyone above covered it. Oval the offset hole on your pulley.

 

[Garrick 1959]

Everyone above covered it. Oval the offset hole on your pulley.

I agree with the Face Diaper comment ;)

 

[pnora]

To everyone,
Thank you for your input and suggestions, what a great group of folks!
It looks like the consensus is, Chrysler/Dodge did the asymmetric hole thing on the original damper and the pulley. Not sure if an actual Mopar balancer is even made anymore. Classic Industries has one for $516 (out of stock) and don't know if holes are asymmetric on that one. So looks like I'll set up the pulley on my X Y table on the drill press with a rotary cutter bit and elongate the hole for the new balancer, is the best value to keep her on the road. This car will never be a Concours type show car. She's nice but I like to drive her and not just look at her. ;)
I have attached a picture of what started this whole journey. Along with prep for new TC. Went to move the car out of my shop for another project she sprung a leak... Notice the top bolt boss is almost gone and the groove to the left of the boss I did with my finger nail... New timing cover fixes that. At the bottom of the picture is the factory damper and pulley... Not sure if the correct coolant was used in it. Certainly will flush and put the correct in to help the new cover not corrode. Not sure by the time the new one does Ill need to worry about it. ;)

View attachment 1982093

View attachment 1982094

I sure hope you replaced the timing chain being that far into it and looking at the overall condition.

 

[Garrick 1959]

I sure hope you replaced the timing chain being that far into it and looking at the overall condition.

Indeed, doing a LOT of clean too

 

[69Bee]

Here are 5 in stock at Summit Racing under $200...

1) www.summitracing.com/parts/pqx-2331841/make/dodge/model/dart/year/1970
2) www.summitracing.com/parts/sum-c4277/make/dodge/model/dart/year/1970
3) www.summitracing.com/parts/sum-163273/make/dodge/model/dart/year/1970
4) www.summitracing.com/parts/pbb-pb1004n
5) www.summitracing.com/parts/pbb-pb1004ss

 

[Garrick 1959]

Here are 5 in stock at Summit Racing under $200...

1) www.summitracing.com/parts/pqx-2331841/make/dodge/model/dart/year/1970
2) www.summitracing.com/parts/sum-c4277/make/dodge/model/dart/year/1970
3) www.summitracing.com/parts/sum-163273/make/dodge/model/dart/year/1970
4) www.summitracing.com/parts/pbb-pb1004n
5) www.summitracing.com/parts/pbb-pb1004ss

Yup the 1st one on your list is the one I bought from PRW 2331841 Their tech support also said what the contributors here said... "Elongate the one hole"
thank you for the information!

 

[Garrick 1959]

Project update,
Elongated hole, cleaned and prepped pulley ready for Paint!

 

[Milo]

You have to turn it so only one hole dont line up then put some chalk on the side of the hole you want to elongate with a file. I have done a few

 

[Garrick 1959]

Exactly, This is my 1st im just glad can still get parts for the car and able to fix it!

 

[1danc]

Glad you didn't ask that question at Thanksgiving , might have been a food fight - General Treatment , Oval the hole !