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Engine New 347 Smokes, Oily Plugs

  • Thread starter Thread starter s0lidllama
  • Start date Start date Aug 2, 2012

s0lidllama

Member
Nov 11, 2010
30
0
6
Aug 2, 2012
#1
  • Aug 2, 2012
  • #1
ok guys heres my dilema

i bought a prebuilt 347 never been run. swapped out my 302 and carbed it. pvc runs from valve cover to carb, and i have a breather on the other cylinder. put it all together and fired her up and she smokes like a banshee. im talking thick heavy smoke at idle and when you rev it. i drove it around the neighbor hood and you could tell which way i went by following the trail of smoke. pulled the plugs and all 8 were covered in oil deposits. cleaned off the plugs, tightened things down ran it again and the plugs got covered in oil again.

i checked intake gaskets, valve cover gaskets, seals are new, guides are good. no oil on the intake walls, pcv isnt leaking oil either.

all thats left are rings right?
any ideas?
 

a91what

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Apr 6, 2011
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Aug 2, 2012
#2
  • Aug 2, 2012
  • #2
Where did you buy the 347? It sounds like rings to me, did you break it in?
 

s0lidllama

Member
Nov 11, 2010
30
0
6
Aug 2, 2012
#3
  • Aug 2, 2012
  • #3
i bought from a guy not a shop.

havent broken it in besides the 5 miles. i didnt want to drive it any more than that in case the massive amount of smoke and oil on the plugs isnt normal
 

a91what

SendMeUrDataLog
10 Year Member
Apr 6, 2011
10,739
6,720
214
Hillsborough county
Aug 2, 2012
#4
  • Aug 2, 2012
  • #4
Well thats not normal, I have a feelin he did somethin wrong. Maybe put the rings on upside down (i dont really know what happens when you do this just my best guess) When I rebuilt my engine it didnt smoke not one iota. let her idle for about 10 mins then gave her hell she runs great.
 

s0lidllama

Member
Nov 11, 2010
30
0
6
Aug 2, 2012
#5
  • Aug 2, 2012
  • #5
ok well i guess that answers it then. my neighbor suggested the rings might be upside down too or the gaps not staggered. thanks for the help
 
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