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For the Entertainment of Others, a Little Game

Horseplay

Horseplay

I Don't Care. Do you?
Donator
It's been slow around here for a while so I will share a tale at my own expense just to give everyone something fun to read and a game of detective mechanic to play.

A couple weeks ago I had a rare free weekend so I did a quick oil change, washed the car and took it out for a weekend cruise. Everything was going great until I came to a stop light. First car at the line. Love it when that happens. I survey the landscape, evaluating the cars about and looking for any cars with lights on the roof. Coast is clear so when it flashed green I hit the skinny pedal more than I should. It launches really strong and straight and stay in it a bit, letting off on the shift to 3rd so as not to go too fast. Glance up in the rear view expecting to see the cars that were behind looking like little specs in the distance. But I don't see any cars. Because the road is engulfed in an ugly, dense cloud of grayish-blue smoke. Yeah. Yikes.

So I pull off into the next shopping center parking lot and do an immediate assessment of what just happened. Oil pressure is excellent. Temp is good. Engine sounds really great. Maybe it wasn't me. Maybe there was some truck or something I hadn't noticed before back there. That must be it. I give the engine a quick rev, watching out back. Nothing. Cool. That scared the crap out of me, to be honest. Nerves calm down. All's good. I shift into gear and exit the lots onto the main road. Give it some gas, shift into 2nd more gas, third. Look in the mirror and see I am crop dusting the pavement. SOB!

Close to home I pull over again and phone the wife. When she answers I give her a quick run down of whats happened. Not sure why, its not like she can do anything to help me. I find out she and the boy are out and just a few blocks away. I decide to have her come over to where I am at and follow me home. Its not too far and I figured I could limp it on the side streets without causing any real issues. So as we are driving I call her and ask if she can tell me if it is smoking out one pipe more than the other. From what I had seen earlier it looked very much like the smoke was concentrated on the drivers side. I have an "X" pipe but that's more for scavaging affect than anything so not much would crossover, I figured.
She confirmed "when it smokes its pouring out the drivers side pipe". It only smokes though when I give it more than an off idle amount of pedal. And also, apparently only when in gear, actually moving and hitting the gas.

A bit about my car for those that may not know. The engine was completely built and installed last year by yours truly. It has just 1500 miles on it. It's a very healthy bored and stroked Ford block 302 (now 347) with nothing but the best in terms of parts. High compression, stupid big roller cam and fed by a FiTech carb style injection system. It has run flawlessly its whole short life and it is STRONG. Even when smoking :mad: It's all business and built to be abused.

So there are the clues. I've given you everything I had to go on when I started trying to fix it myself. Time to play detective mechanic. What do you think I'm up against? I will take questions about any other particular details and answer to the best of my ability with the information available. I will say this is not an open ended game. It took some time and effort but I have fixed my car at this point. Just thought it might be fun for all to try and figure it out. See who's on top of their game.

Hey {.}, you don't get to play since I've already told you. And no clues!
 
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You have power steering? I wonder if the engine/exhaust manifolds are hitting the PS lines while accelerating...
 
Midlife said:
You have power steering? I wonder if the engine/exhaust manifolds are hitting the PS lines while accelerating...
Click to expand...
I do have PS but an aftermarket set-up. I have the Borgeson power-box and a...forgive me...Saginaw pump. The lines, however, route directly out of the pump through the inner fender into the wheel well and then return back at the pump. They are not the culprit this time.
 
Good thought. That was mine too. Seemed to fit the circumstances. Plus, I did rush the change trying to get out of the house and using an old partial 5 gallon jug and a new one I kind of guestimated the amount I put in. So I checked the stick and it did read quite a bit over so I removed about 2/3rds of a qt. Figured I had it licked until I took the test drive and soon as it got warm I gave it some gas and smoke city again. Damn it.

Back to the garage. Sorry. Try again.
 
There are stem seals. But like you, I suspected them as well. Pulling the valve cover was like opening a jewelry box. Everything inside glistened with a light coating of clean motor oil. The Comp Ultra rockers perfectly aligned on the valve tips just as I had set them up during the build. What little I could see of the seals without removing the springs appeared to be in correct position and good condition. Nothing visually seemed a concern.

I can tell you now, though I didn’t know it at that point, the seals were not the issue.
 
Patrick Stapler said:
Misaligned or incorrect intake manifold gaskets?
Click to expand...
Nope. Not intake gaskets/leak. I port match my stuff very closely with includes marking the heads and intake for proper alignment during assembly. Done so many this way I've never had an issue. Well, now that I just jinxed myself...
 
Hmm maybe it's something crazy, like the pcv is hooked up wrong and it actually sucks oil back through the line into the cylinders. That's my stab in the dark.
 
I was waiting for the PCV guess. I thought it a prime candidate at one point but nope. Valve guides or even a head gasket at this point would have been acceptable to me. Slightly better than a broken oil ring, for example. So since all the "simple" top end stuff had been ruled out I went and did a full compression check of all 8 cylinders. Freaking perfect. Not even a half pound difference between any of them.

This has been going on for days now. Me wrenching on the car trying to find the issue. I'd steal an hour here or there each day and go chasing after it only to come up empty. If you review everything mentioned here you'll have to agree that at this point what the hell are we (I) missing?!

So I stepped back and went over it all again. It just didn't add up. So I took the car out for a cruise around the neighborhood listening and watching for anything which might help solve the riddle of the smoke. All I got was the same thing. Runs great. Sounds great. Clear exhaust. So I stabbed it and the damn cloud appears behind me again. Mother....! :mad: Fed up I wheel it home and pull in the garage. Pop the hood, stand by the driver's side fender and with it running reach over and manually give it some throttle and watch down the side of the car at the back for the ensuing cloud to form. Nothing. That's right, I thought, it only does it when moving. Again thoughts of an oil rush to the rear formulate in my head. But none of the resulting stuff has added up. This is beyond frustrating. And then I saw it. Out of the corner of my eye. A wisp of smoke. Burning oil. I turn back to the engine but there is nothing there. Hmmm. I blip the throttle again. A small puff of smoke comes up from what looks like the header flange right next to the #7 spark plug. Finally something tangible.I was on the trail.

That's my last clue. From there I finally solved the mystery. Who's got it now?
 
Only the left side of the exhaust (driver side) smokes , under load .................valve cover leak at the #7 sparkplug ?
But then the left exhaust wouldn't smoke .....or did it seems to smoke ??
 
Now you're scratching your head like I was, Bruno. What seemed pretty straight forward didn't lead anywhere we might expect. So I had to reevaluate things I thought I knew. If the smoke was pouring out of the exhaust (primarily drivers side, per eye witnesses) that would certainly confirm oil was finding it's way into at least one cylinder on the drivers side bank. It's possible a valve cover leak could be to blame, I guess. Oil seeping down to a poorly sealed header gasket and being sucked into the pipe where it would then burn off creating the smoke. But if that was the case why only when driving and under a fair amount of throttle? It all still seemed odd and a reach.

So I checked the cover and found it tight as a drum and no leaks. Same for the header. At this point I am losing my mind. So I fire it up and while running start looking EVERYWHERE for signs of an oil leak. Can't find a thing. So I hit the throttle by hand again and sure as shit a puff of bluish smoke arises around the #7 plug area. Again. Another puff. Try as I might I simply cannot see a cause. Beyond frustrated I walk away for a while. Let it and myself cool down a bit.

I return to the car with my new Harbor Freight inspection camera in hand. I start poking the small remote camera into the area around the spark plug area. It's not long and I finally get a clue as to what's happening. I almost had to laugh.

Last shot to see if you guys can figure it out. There are enough clues here, I promise. For those that might be actual mechanics or field techs or the like I can tell you what I considered my "rule number 1" in those days applies and would have helped if I would have remembered and followed it.
 
Blinker fluid found its way back through the wiring into the ignition system. Weak spark plug wire on #7 was path of least resistance. As each pulse of ignition came through, #7 plug was squirting blinker fluid into the cylinder causing the smoke.

Loose plug?
 
Yeah, this is a tough one to begin with but even harder trying to figure out just from my written clues. My Rule #1 as a field tech was always to question whatever the customer (witness) tells you. They are rarely reliable. Shame on me for forgetting.

In this case, my eyewitnesses were genuine in their assessment but allowed my question to steer their answer. I asked them, "Is it coming out more from the driver's side pipe or equal?". So they (wife and son) took it as a given the smoke was coming out of the exhaust and noted it appeared to be much more the driver's side. As I could hardly do my own inspection as I would need to be both driver and somehow rear view spectator I just rolled with what I was told. Should have had the kid take a video so I could see firsthand. Might have saved me not only time but a ton of stress brought on by my fears of complete engine rebuild.

Also, we are all a bunch of old, classic car type guys here and some may have very well never encountered this before. I know I hadn't.

LAST CLUE to try and help guide you. There is and never was any smoke coming out my exhaust. It may have looked like it but thatss because it was actually blowing along under the car while driving and exiting under and around the exhaust tip. It may very well have been so thick and engulfing they couldn't tell. I will never know now. One other tidbit to really make it easy. Remember, this is a newer 90s block.
 
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