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Dead cylinder

  • Thread starter Thread starter rc4mike
  • Start date Start date Apr 18, 2012
R

rc4mike

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Oct 10, 2006
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Apr 18, 2012
#1
  • Apr 18, 2012
  • #1
I need some help. My 351 has been running rough. So I ran a cylinder balance test and found #2 cylinder is dead. Ran test 3 times same result. So I switched injector w #1 but # 2 still dead. Switched plugs, still #2 dead. Checked spark on #2 by grounding plug on block and I have spark. Tested injector leads with noid light and have power. Cylinder has compression. Valves and rockers move as they should. engine was built 4 yrs ago and has maybe 3 hrs run time. Alumin heads.

I've run out of options. Any ideas?

Thanks
 

jrichker

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Apr 18, 2012
#2
  • Apr 18, 2012
  • #2
Spark tends to blow out under pressure, so parts may seem to work when not subject to the increased stress of firing under compression. That means you have to look carefully when inspecting for problems and defects.
Check the cap for carbon tracks and cracks.
Check spark plug wire resistance: recommended resistance is 3000-8000 ohms per foot of length.
 
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rc4mike

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Apr 19, 2012
#3
  • Apr 19, 2012
  • #3
3k to 8k? I'm getting 50 ohms per foot on the three wires I checked.
 

jrichker

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#4
  • Apr 19, 2012
  • #4
rc4mike said:
3k to 8k? I'm getting 50 ohms per foot on the three wires I checked.
Click to expand...
That's OK for the coiled wire type spark plugs. Taylor and Accel both make spark plug wires with a coiled metal wire core.
 
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rc4mike

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Apr 19, 2012
#5
  • Apr 19, 2012
  • #5
Mine are msd red wires. I think 50 ohms is about right for the better wires. So now what? I'm thinking I'll go back and check compression on all cylinders. Prob also re-gap my plugs as I didn't check the, when I installed
 
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WashingtonS87

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May 3, 2012
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May 3, 2012
#6
  • May 3, 2012
  • #6
jrichker said:
That's OK for the coiled wire type spark plugs. Taylor and Accel both make spark plug wires with a coiled metal wire core.
Click to expand...
I totally agree with you..
 
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