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Engine Guru's Strut Your Stuff

  • Thread starter Thread starter mustang 88
  • Start date Start date Nov 12, 2014
M

mustang 88

Member
Oct 21, 2012
60
4
9
cleveland ga
Nov 12, 2014
#1
  • Nov 12, 2014
  • #1
I need real help. I have a brand new z363 boss short block with 200 miles on it. I have AFR 185's (1 year old) with 1.72 scorpion rocker,x303 cam,and new trick flow R series upper and lower intake. Today was the first day that I notices it smoked at low rpm's just for a couple of seconds then stopped and then did it again about 20 mins later. I do have a burn off hose from the valve cover to header collector. Also smoked very heavy after setting for 3 hrs ,again just for a couple of seconds.
 
L

Lscam580

Active Member
Aug 27, 2014
119
18
28
Grand Rapids Mi
Nov 12, 2014
#2
  • Nov 12, 2014
  • #2
Check your valve seals, see if they are pushed up to the top of the valve. #2) while you have the valve cover off look at the oil return holes running through the head to the block, with a flash light shine down the oil hole to see if you can see the head gasket overlapping the hole. Which in turn will restrict the oil flow and will back up in the head and can have drainage along the valve and leak into the cylinder creating smoke which you are experiencing.
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
8,859
214
In the garage
Nov 12, 2014
#3
  • Nov 12, 2014
  • #3
smoking on start up is usually valve seals. Does is smoke at all on deceleration?
 
J

jka

5 Year Member
Jan 17, 2010
339
23
29
Nov 13, 2014
#4
  • Nov 13, 2014
  • #4
It could be the pcv valve/crankcase breather. Also could be the baffle in the lower intake causing it to suck oil and cause it to smoke.
 

RacEoHolic330

I like to dress like a pretty girl
15 Year Member
Mar 4, 2003
4,014
1,698
203
Allentown, PA
Nov 13, 2014
#5
  • Nov 13, 2014
  • #5
A leak down test confirmed the source of my smoking on decel issue. It was worth the $60 for the tool.
 
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