Smoke everywhere!!
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From: Green Bay USA
Smoke everywhere!!
I'm looking for suggestions.
I have a '86 f250 w/351w. I know I have a dead cylinder. It still runs ok and has oil pressure. I will go down to Autozone and get a long block just as soon as I get the $. But the problem is this:
When you give it a little gas (2000-3000 rpm or so) It smokes like you wouldn't believe out of the oil fill cap as well the pcv valve and anywhere else it can. I think it is exhaust smoke, as opposed to pure oil smoke.
If it wasn't for the smoke, I could use it for 3 miles runs which is 80% of its use. I can't see where anything is plugged. One thing I should mention is that there is so much crankcase pressure that it blew the oil fill cap right off and put a BIG dent in my hood.
Can anyone suggest something to look for to make this thing go another month. If it ran bad I would throw in the towel, but the fact that it runs and drives ok just makes me think it's not dead yet. Asside from the smoke pouring over the hood it runs ok at 50mph.
Holding onto hope,
ScottyB.
I have a '86 f250 w/351w. I know I have a dead cylinder. It still runs ok and has oil pressure. I will go down to Autozone and get a long block just as soon as I get the $. But the problem is this:
When you give it a little gas (2000-3000 rpm or so) It smokes like you wouldn't believe out of the oil fill cap as well the pcv valve and anywhere else it can. I think it is exhaust smoke, as opposed to pure oil smoke.
If it wasn't for the smoke, I could use it for 3 miles runs which is 80% of its use. I can't see where anything is plugged. One thing I should mention is that there is so much crankcase pressure that it blew the oil fill cap right off and put a BIG dent in my hood.
Can anyone suggest something to look for to make this thing go another month. If it ran bad I would throw in the towel, but the fact that it runs and drives ok just makes me think it's not dead yet. Asside from the smoke pouring over the hood it runs ok at 50mph.
Holding onto hope,
ScottyB.
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Joined: Feb 2002
Posts: 1,712
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From: Atlanta, Georgia, USA
Smoke everywhere!!
Get a new PCV valve, and make sure the one you have isn't pluggd somewhere upline. If that doesn't work, you could always use a filtered breather cap instead of a solid cap.
Good Luck!
The TorqueKing
Good Luck!
The TorqueKing
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From: Green Bay USA
Smoke everywhere!!
[updated:LAST EDITED ON 28-Mar-02 AT 04:26 PM (EST)]PCV valve is new.
Oil fill cap IS vented. That's how much pressure was built up. Scary eh? All that pressure built up in about 20 seconds after starting it.
It's almost as if the exhaust is venting into the crankcase. But it runs too smooth for that.
Is there a plugged vaccuum line that would cause this. I gave the lines a once over, but really didn't know what I was looking for.
I also put a hose on the vented oil fill cap going into a (vented)coke bottle so I could see how much oil was blowing out. There is NO oil, just lots of smoke.
Is it possible that at low RPM everything is working fine, but at high RPM something is stopping the exhaust from going out the exhaust pipe. What would cause that?? Can I disable the thingy that restricts the exhaust when the engine is cold?
(I'm really not as stupid as I sound, really!!)
ScottyB.
Oil fill cap IS vented. That's how much pressure was built up. Scary eh? All that pressure built up in about 20 seconds after starting it.
It's almost as if the exhaust is venting into the crankcase. But it runs too smooth for that.
Is there a plugged vaccuum line that would cause this. I gave the lines a once over, but really didn't know what I was looking for.
I also put a hose on the vented oil fill cap going into a (vented)coke bottle so I could see how much oil was blowing out. There is NO oil, just lots of smoke.
Is it possible that at low RPM everything is working fine, but at high RPM something is stopping the exhaust from going out the exhaust pipe. What would cause that?? Can I disable the thingy that restricts the exhaust when the engine is cold?
(I'm really not as stupid as I sound, really!!)
ScottyB.
Posting Guru
Joined: Feb 2002
Posts: 1,712
Likes: 1
From: Atlanta, Georgia, USA
Smoke everywhere!!
I agree with CajunBronco, you must have excessive compression gasses escaping into the crankcase. This scenario would aslo cause the volume to increase linearly with RPM, since faster engine speeds draw more compression gasses in the same amount of time. I would look for a piston ring failure, but a new PCV valve can usually scavenge that amount of volume. You may have a hole in your piston, it's not impossible, and it would certainly put out a tremendous amount of gas into the crankcase. I would be very cautious in driving this engine, since the gasoline in the combustion gasses will break down the oil coating on the load bearing surfaces of your engine, and gasoline in the crankcase will slowly dissolve your oil into sludge. Be careful, and Good Luck.
John F. Daly III
The TorqueKing
John F. Daly III
The TorqueKing
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From: Green Bay USA
Smoke everywhere!!
Thanks guys.
I may have to face the facts that your diagnosis is right on. I'll check it out a bit more this weekend. Then I'll take a trip to Autozone.
Should I plan on new exhaust manifolds or will I be able to reuse the current? The exhaust system looks completely solid.
What else should I pick up with a long block? Keep in mind I will only use this as a weekend truck. Maybe 5000 miles a year.
Thanks
ScottyB.
I may have to face the facts that your diagnosis is right on. I'll check it out a bit more this weekend. Then I'll take a trip to Autozone.
Should I plan on new exhaust manifolds or will I be able to reuse the current? The exhaust system looks completely solid.
What else should I pick up with a long block? Keep in mind I will only use this as a weekend truck. Maybe 5000 miles a year.
Thanks
ScottyB.
