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Old 09-23-2016, 07:34 AM   #1
Grumpy old man
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Location: Gods country East,Tn
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Wink Re: black coolant

Pull the plugs , if you find one that looks steam cleaned you found your leak .
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1967 Factory short bed - Old school
'71 - 350 / 4bolt / 487 heads / Edelbrock C3BX
Muncie M-22 4 speed / Hurst Comp plus
Factory 12 bolt posi 3.73 / 255-70-15
Smoothed firewall / Factory cowl induction
Power disc brakes / power steering / 3.5-5" drop
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Old 09-23-2016, 05:27 PM   #2
merlin3
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Re: black coolant

well,i pulled the plugs and found #1 plug almost white and the rest very dark with carbon,[still need to adjust carb.]then i took the spill free funnel off, looked in the radiator and could see perfect green coolant,so when running with the funnel is the only time i see black coolant [in funnel]i have all holes in the intake and water pump for heater hoses plugged because i do not have the heat hooked up,very confused here-thanks for the help.
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Old 09-24-2016, 04:45 AM   #3
Grumpy old man
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Re: black coolant

Switch the "white "plug with one of the dark ones and drive it a bit and pull those two plugs again , if the #1 plug is white again you have found your leak in that cylinder , be it a Crack or bad head gasket . Before getting too crazy dump some Bars head gasket sealer in the radiator and see if that solves your #1 cylinder problem . Just a very small amount of water/coolant will give that steam cleaned / white plug look .
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1967 Factory short bed - Old school
'71 - 350 / 4bolt / 487 heads / Edelbrock C3BX
Muncie M-22 4 speed / Hurst Comp plus
Factory 12 bolt posi 3.73 / 255-70-15
Smoothed firewall / Factory cowl induction
Power disc brakes / power steering / 3.5-5" drop
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