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fuel or oil leak at mid-high rpm?

6

67resto-coupe

Member
so, on top of my rich carburetor (still unresolved, btw) issues, i have discovered another issue of more serious concern. while i rev the engine by hand, i'm standing next to the driver's side fender, i can see some type of fluid squirting out from somewhere near the #7 cylinder. this "mystery" fluid squirts out then immediately gets vaporized on the header. ***POOOFFF*** it's a whitish colored smoke - smells like oil, but i can't tell. would this indicate some type of fatal head gasket issue? my oil is still as clear as honey, so i'm ruling out a head gasket. the only thing i can think of is unburnt fuel squirting out of of the plug socket, somehow, and burning off. i can't really see any type of residue either on the header, so maybe gas?

as for the carb problem, i've replaced the gas tank and have installed a new hi-torq mini starter....car turns and starts better, but still fat once it gets warmed up. i'm going to check the butterflies, choke and acc.pump, after i remove the carb and clean it.

thanks.
 
White colored smoke: water
Grey or blue colored smoke: oil
Fuel probably would immediately vaporize or flash-burn upon contact with a hot header.
 
This may be a stretch but, do you have a 5.0 in the car. The old dipstick hole is right there around the #7 cyl. I just went thru your past posts and noticed you have the 5.0. Did you plug the OEM dipstick hole down below the #7 cyl? It is on the block just above the ol pan.
 
To help with determining the fluid, how about holding a sheet of paper or a Kleenex where it's going to squirt, in front of the header. Then rev the engine and let it squirt on your paper or Kleenex. Then you can quickly move it away from the heat, and examine it for color and odor to help determine what it is.

My guess is that it's either coolant or fuel. Oil would be leaving a residue on the header, no matter how hot the header is.

If it's coolant, you have either a blown head gasket or cracked head. Might want to do a pressure check on the coolant system, listening and watching in that area for a leak.
 
6t6red - dipstick hole? really? huh, never even considered that. that would make total sense, too. i'll do some internet research to see where or what it may look like and give it a check. what size plug? that would make sense, as the "spurt" is directly related to the rpm....the more rpm, the more squirting/splashing....excellent! i'll keep my fingers-crossed. thanks.
 
67 I found an old pic of mine and it shows the hole. It is below the freeze plug on the right. You will see the radius cut-out just above the oil pan and the dip stick hole is in that radius. You can use a wooden dowel to fill the hole. I haven't had any leaks using the dowel.
DSC00197.jpg
 
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you are spot-on. thank you, sir. i ended up cutting a 3/8 bolt to about 1" total length, spread a nice thick film of blue silicone gasket material and pushed it in. i think that'll do it. AWESOME!! for a minute, i thought my "new" crate motor had a bad assembly...whew! now back to carburetion tuning....
 
I've heard some people use a 3/8 dowel to plug the hole. It will soak up some oil and swell up so that it's a tight fit.
 
"67resto-coupe" said:
you are spot-on. thank you, sir. i ended up cutting a 3/8 bolt to about 1" total length, spread a nice thick film of blue silicone gasket material and pushed it in. i think that'll do it. AWESOME!! for a minute, i thought my "new" crate motor had a bad assembly...whew! now back to carburetion tuning....
Click to expand...

You'd better look at those headers again. They probably look like shart underneath there. Oil will not burn completely off. It will leave a very nasty stain that is very hard to get off of certain finishes, like nickel, ceramic, etc.
 
"66gt350" said:
I've heard some people use a 3/8 dowel to plug the hole. It will soak up some oil and swell up so that it's a tight fit.
Click to expand...


That's what I've done with my 5.0. Cheap and effective.
 
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