Author Topic: Need help with harmonic balancer  (Read 685 times)

Offline 7212Mopar

  • Full Member
  • ***
  • Posts: 595
Need help with harmonic balancer
« on: November 22, 2013 - 11:53:28 PM »
My old water pump blew a few weeks back. After I took it off I found the water passages of the timming cover was badly corroded so I picked up an aftermarket version. Everything bolted up good until I got to the balancer. I pressed the balancer in until the edge almost touch the degree mark on the timming cover. I then started the crankshaft bolt but as I tightened it the balancer got pushed in further and jammed against the timming cover. No way I can torque the bolt to 135 ft lbs without causing damage to something.

The engine is a 70 340 with a forged steel crank and the bolt is 2-1/4" long which I verified to be correct for small block. The crankshaft bolt hole bottom to face of balancer is about 2-3/4" deep. The diameter of the balancer is about 7-1/4" and it looks like correct for a forged crankshaft. Did I do something wrong or is it another way to tighten the crankshaft bolt? I don't understand why the old cover did not have a problem.
1973 Challenger Rallye, AT with 1971 340
2012 Challenger SRT8 392 YJ,  6 spd




Offline hemiken

  • Sr. Resident
  • ******
  • Posts: 8785
  • Hemi-fied Mopar in Australia
Re: Need help with harmonic balancer
« Reply #1 on: November 23, 2013 - 12:48:03 AM »
can you post up a picture please, sounds like you may have left a spacer out or something that is easily done. It does sound like the bolts are going through the harmonic too far to hit the timing case cover.
1970 Barracuda   (O^--^===|===^--^O)
1971 Barracuda   (O O {]{]{]|[}[}[} O O)
1970 Challenger  (O O [======R/T=] O O)
1971 Challenger  (O O ===== ===== O O)
I pay homage to the best Mopars ever built.

Offline 73EStroker

  • Sr. Member
  • ****
  • Posts: 1343
Re: Need help with harmonic balancer
« Reply #2 on: November 23, 2013 - 10:20:34 AM »
I would measure the depth of the new timing cover compared to the depth of the old one. Otherwise it could be what Hemiken said and you left/there was a spacer left out or something. What about belt alignment when the damper is in too far? Try putting the bottom pulley and belt on. That will tell you where to look.
Barry (Salmon Arm)

Offline 7212Mopar

  • Full Member
  • ***
  • Posts: 595
Re: Need help with harmonic balancer
« Reply #3 on: November 24, 2013 - 02:42:10 AM »
I think the problem was a combination of the timming indicator casting and a tad too much RTV sealant. I ended up doing some grinding to the timming tab on the cover and the balancer seated on the crankshaft. The bolt was then torqued to 135 ft lbs. There was no spacers.
1973 Challenger Rallye, AT with 1971 340
2012 Challenger SRT8 392 YJ,  6 spd