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Motor Still smokes at 200 miles. Maybe a Doofus

568 Views 7 Replies 7 Participants Last post by  mod9
Everytime I go to start my motor a big plume of smoke comes out of the pipes, and when I rev her up a little little puffs come out of the drivers side while it just pours out of the passanger side. When I broke in the cam you are supposed to run the motor at 30 min to break it in. At 15 minutes I shut her down and adjsuted the valves and forgot to hook The #1 cylinder plug wire back up and broke it the cam for another 15 min. could I have damaged something?? I rea feel like an idiot. I also am running Forged pistons with moly rings a cam with 236 duration at .050 and .571 lift with standard style valve seals, hope this helps any. Thanx a Bunch
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ok, first things first. What color is the smoke? It is normal to have a little white smoke and drips of water from condensate when you first fire up. Tends to come more from one side than the other. If that is not your situation, then run your finger round the inside of the tailpipe. OUch, hot wasn't it. Wait for the car to cool (haha). If your finger is dry and sooty with black soot, that is unburnt gas. Carb could be rich - You could have a dead cylinder - be it from improper valve adjustment, a fouled plug, bad electrical to that cylinder. Are you getting any clackity clack from the valve train or all nice and quiet? Go back to the "doofus" clyinder and pull the plug? What does it look like? If you have not changed the plug from when you broke in the cam, that might be your sole problem. The plug is too fouled to ignite the fuel mixture so you are blowing the unburnt mixture out the tailpipe. It's coming out of both cause of the cross over pipe on your dual exhaust.

If this does not define your problem, then pull all of your plugs and check for oil fouling. This is a black crusting deposit on the center electrode, plus black crud and maybe even a little oil, around the thread area. It is not unusual for your rings to take 500 miles to seat and stop leaking oil.

Lastly, you can check the spark. One way to do this is to start the car, pull the plug wires off one at a time at the plug (using something INSULATED, not your bare hand, especially with an MSD or Jacobs ignition - ouch). First of all, if everything is ok, when you pull a plug wire, the engine should run noticeably rougher. IN theory, if it runs the same, that is the bad cylinder. I would try grounding the plug wire to the shock tower or some other convenient area to see if you have a spark jumping that cap between the plug boot and ground. Might have to stick something like a wire, piece of coathanger, screwdriver, etc, up the plug boot to contact the metal connection up there. I would check these one at a time, and that should eliminate a misfire due to electrical malfunction.

In my inexpert opinion, you did NOT damage your cam by runnign it with a dead cylinder during break-in. What damages a cam at that point would be lack of lubrication, a bad lifter (hydrolic lifter collapsed), improper valve adjustment, improper valvesprings, incorrect pushrod length. In other words, you have to have a mechanical problem to mechanically damage the cam. The cam is a "bumpstick" and has no moving parts to get messed up. AS long as it has lubricant, it can only be damaged by "impact" or bad cam bearings, improper torque on the reainer bolt (should be 45 ftlbs) that lets it walk in the bearings.

Bottom line, I think you have a fouled plug that needs replaced, then everything will be ok. Little smokey till your rings seat.

good luck. Write us back and tell us what the problem was and fix that worked, ok? Thanks,
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Are you sure it's smoke, and not steam?
Did you run the motor at 2000 rpm during break-in? Running the motor at idle may destroy the cam during break-in.
Do you have an aluminum intake manifold?

One thing that can cause smoke is an incorrectly installed intake. If it isn't sealed properly, oil is sucked into the heads and out the tail pipes. Did you use RTV between the intake and block or the cork pieces that came with the gasket kit? Which intake gaskets did you use and did you put any sealant on them? Did you properly torque the intake bolts and recheck them after run-in and a couple times more after run-in?

Also, would help to fill out your bio.

Good luck.
When you get things sorted out, keep in mind that forged pistons are supposed to be a bit loose in the cylinder, and chrome-moly rings don't seat quickly. I too have that combination, and it seems like the initial mild oil consumption has gradually decreased as time has passed. Down to a quart every 2000 miles now.
Did you have the piston-to-valve clearance checked? Not certain what motor you have, but I had a simular problem with smoking that was a result to too little clearance years ago on a Ford 427MR motor. Bent a few pushrods, and damaged a few valve seals.

good luck
I don't think you have a problem. Damn moly rings take forever to seat. If your car runs cold it makes it worse. What I like to do with moly rings is to block off the radiator and start the car and let idle until it reachs 220 degrees and shut it off and let cool. They seam to seat faster that way.

69 Mach 1 427 Windsor
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