What I have: 87 v8(318) 2bbl 192K and here is what has happened.

About 2 weeks ago I started hearing an occasional clanking/grinding noise at startup that goes away as the engine warms and the thermostat opens. I thought oh great, water pump failure. I've had some unexplained coolant lossage, more than a half gallon, to back up that theory. The sound is coming from dead on center of the engine from the front. A friend had agreed to help me do the pump so when I arrive at his place, first thing we did was disconnect the belts and crank it over to make sure that one of the pulleys wasn't causing the problem. The noise is still there, some words were said! Without the belts the water pump isn't connected so the water pump isnt the problem, neither is the alternator nor PS pump.

Whatever it is it is robbing power from the engine. because since it started it has been a real bear to start though until now I had been attributing that to the single digit temps.

Since we had also planned on changing the oil, we went ahead and did that. Oil was very dark, but I idle the engine for a long time often when I'm out and running my computer off the inverter. I go though about 20 gallons of gas a week normally between driving and idling. My habbit has been to drive for an hour after work because the engine doesn't start well in the morning when it is cold if I don't.

Also we found the plug on cylinder 5 was so loose I could take it out by hand. so that was put back in.
The engine has been occasionally backfiring when it fails to start in the cold weather. Though that may be from the loose plug. The plug looked like the picture in the haynes manual for the carbon deposits which makes sense if the plug isn't firing all of the time because it wasn't fully seated in the hole and making good contact.

I still have been unable to get the computer to flash the CEL to see if there are any codes in it. Though the light is on before it cranks over when I start it and will come on if it stalls while I'm driving. I had assumed the stall was from low compression and really cold air since once the thermostat opens it never never idles down or stalls.

I've felt around the oil pan and determined that the noise is from something striking it, from the inside. The pan doesn't appear to be deformed, at least not yet. I was wondering if it was possible to drop the oil pan without lifting the engine off the engine mounts. The clearance looks tight. I know the oil pump pickup is in the rear of the pan,

I don't know what could be striking the pan without causing the engine to totally mangle itself internally. I have probably driven 60 miles with it the way it is. Though after the oil change it seems louder than it was though that may be cause im listening for it more. Also I have noticed that the noise is louder when there is no load on the engine as in neutral. There is no noise if the engine is off and the van is rolling either.

What I am looking for is things to check to narrow down the problem and if a single cylinder is affected to figure out a way to disable it so I can run on the other 7 without fearing immanent catastrophic failure. The thought I had on that was to wedge the intake valve closed, remove the plug and some how keep the piston head high in the cylinder.

Any goofy ideas are welcome, I could use a good laugh about now, some may even be tried.
edit was to fix a typo I missed

 

Sounds more like a starter to flywheel issue. You could check and see if the flywheel is loose and/or that the starter is disengaging after startup.

 

The starter is disengaging fine.I feel the the knock on the bottom of the oil pan the strongest vibration is around the front drivers side corner of the lower section of the oil pan.

Front
{__________ } transmission
cross \ |
member \ /
\_________+
^^
the knock is about here (^^) on the drivers side, as a guess it is under #3 #5 deffinately on the odd side of the block. The funny thing is tht Im not getting any misfire notes, or knock retardation. well let me rephrase that, I'm asuming that a regular misfire would set the CEL, but that as I've said is only on briefly while starting.

 

In 87 there are no misfire computer codes recorded in the computer. The closest you can come to that is if you get an oxygen sensor code to indicate that your air/fuel mix is out of whack.

Onto your knock, the only thing in the area you've mentioned that could be loose is the oil pickup tube. If you're 100% sure that your feeling a knock down there and it's not just traveling through the metal from somewhere else, then I'd start leaning toward a spun main bearing as the problem. A spun rod bearing noise would get worse has the engine heats up and load is applied, also your oil pressure drops significantly. A spun main bearing is just the opposite, it gets quieter as the engine heats up and load is increased and there is no noticeable change in oil pressure.In addition, if it's arear main bearing you will get noise if you manually downshift because the force from the tranny pushing the crankshaft to go faster stresses the bearing. The fact that the noise seems to have gotten worse after the oil change is another clue. Clean oil does not have dirt and other contaminates in it to help dull the knocking noise. Kind of along the lines of how sound will travel better in water than mud.

 

Yikes, after I posted it, the graphic looked correct, now that Im looking at it it is toitally in the wrong place. The ^^ should be right at the beginning of the lower part of the oil pan, closest to the front. of the lower section and deffinately on the drivers side of the pan. If it is the pickup, which I thought didn't move, then there is something else really wrong.

I have low oil preassure but the dipstick is reading full. I am blowing blue smoke all of the time, now that it has warmed up outside, that my be the 10w30 thin oil I use in the winter blowing by too easilly. I normally use HD40. When I did the oil last weekend I used 10W30, and threw in a quart of Lucas to top it off. This weekend the weather doesnt look like it will be cooperating for under car work outside. I'm currently debating if I want to go though the effort to drop the pan and look, engine mount bolts in my experince are never easy to remove. If I decide to gamble on breaking it further by dropping the pan and checking, I'll try to take some pictures of what I find. I will say that Im amazed that it still runs.

 

Blue smoke! Hmmm, using 10W-30 shouldn't cause that. With the blue smoke factor thrown in there, diagnostics could shift toward a cracked ring or piston. Have you pulled out the plugs yet to see if any one of them has heavy deposits or is oil coated?

 

I thought I'd update this, and may do so one more time if I get the chance to drop the pan and actually look.

I pulled it from the road towards the end of the month and started biking the 3 miles to work. Why? well not because of the engine, but because I nearly lost the upper ball joint on the drivers front. With all of the other things it just wasnt worth fixing it. I have started moving stuff over to an '85 Ramcharger 150 Royal SE 2wd that I picked up cheaply. It has some problems but runs, and that is important. It too has the 318. Most of the dash components are the same just in different places. I miss having the wheel well to rest my left foot on though.

Igadget