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Engine Questions about a front main seal leak and a possible cause

  • Thread starter Thread starter 93silverlx50
  • Start date Start date Jun 16, 2018

93silverlx50

Member
Jun 12, 2017
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Jun 16, 2018
#1
  • Jun 16, 2018
  • #1
I was going to drive my car for the first time since putting the new motor in. Its a 347 with an S Trim.

Ive let it idle and then today I gave it some gas, only to about 2K to 2500 RPMs. After that I noticed an oil leak that looks like it is coming from the front main seal directly behind the harmonic balancer. It only leaks after Ive reved it a bit, it doesnt leak at idle. Im going to get a new pcv tomorrow and see if it still leaks after that. Could a bad pcv cause that and actually fix the leak by properly venting the crankcase?

Also, I have a 7qt Moroso pan but I did not install a dipstick yet. My stocker ended up on the floor under the motor I pulled out and was smashed. I know dipstick tubes dont vent the motor but would that be a backup venting method which would prevent the motor from venting and leaking from the front main seal? (My last motor, the dipstick was always sticking out of the tube)
 
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