Whats happening in #6 Cylinder

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straightlinespeed

straightlinespeed

Sometimes I pretend to be normal
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My engine only has 300 miles on it from the rebuild. I pulled the plugs to swap them to something different. This was #6 Cylinder on my 360.

View attachment #6 Plug (1024x576).jpg

What is causing this? I shined a light into the plug hole and the entire piston is carboned. I know I have a questionable set of plug wires on the car and I just ordered a good set up. It almost looks like the valve stem seals?? Whats your opinions?
 
Is it puffing at first start up? How about when the vacuum is high...throttle shut going down hill?
 
is it oil of fuel? looks like oil from the pic. did you seat the rings properly??
 
inkjunkie said:
Is it puffing at first start up? How about when the vacuum is high...throttle shut going down hill?
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I really haven't noticed a definite puff of blue smoke, but as I have been tuning it. It does seem to smoke more than what I think is normal. While driving it I have not noticed any smoke but then again I have not really paid attention behind me.
 
805moparkid said:
is it oil of fuel? looks like oil from the pic. did you seat the rings properly??
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It definitely smells like oil. I did break the engine in properly for 20 minutes and used break in oil. Then after break in took it for about a 10 mile drive. I got home and shut it off for about 15 minutes until a friend came over and wanted to hear it. I started it up and let it idle. Then gave it a quick rev to about 3k. We heard a loud noise from the engine area. I shut the car off, looked around and couldnt find any thing. I started it back up and ran fine. I did pull the first set of plugs and they were all carboned up and assumed this was because we didnt have the carb or timing set right yet. That is when I installed the set of plugs I just pulled out today.

All of the other cylinders looked good and the plugs looked normal. It was just this one cylinder that is still all nasty looking. Oh and I also did a compression check on all the cylinders. They all ranged from 140-150.

Could that loud noise have been a piston ring?
 
straightlinespeed said:
It definitely smells like oil. I did break the engine in properly for 20 minutes and used break in oil. Then after break in took it for about a 10 mile drive. I got home and shut it off for about 15 minutes until a friend came over and wanted to hear it. I started it up and let it idle. Then gave it a quick rev to about 3k. We heard a loud noise from the engine area. I shut the car off, looked around and couldnt find any thing. I started it back up and ran fine. I did pull the first set of plugs and they were all carboned up and assumed this was because we didnt have the carb or timing set right yet. That is when I installed the set of plugs I just pulled out today.

All of the other cylinders looked good and the plugs looked normal. It was just this one cylinder that is still all nasty looking. Oh and I also did a compression check on all the cylinders. They all ranged from 140-150.

Could that loud noise have been a piston ring?
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you need to let it cool all the way down over night. then take it out and load the motor, low rpm in 3rd, not lugging though. so take it from the shift point to 3 grand then slow back down and do it again a dozen times or so. this builds cylinder pressure and helps to seat the rings.

if I had a guess you didn't seat the rings and maybe popped an intake gasket.
 
805moparkid said:
you need to let it cool all the way down over night. then take it out and load the motor, low rpm in 3rd, not lugging though. so take it from the shift point to 3 grand then slow back down and do it again a dozen times or so. this builds cylinder pressure and helps to seat the rings.

if I had a guess you didn't seat the rings and maybe popped an intake gasket.
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By popped a intake gasket, I assume you mean blew it out? Should I pull the intake and take a look to see if its still good?
 
straightlinespeed said:
By popped a intake gasket, I assume you mean blew it out? Should I pull the intake and take a look to see if its still good?
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well I don't think your there yet... do a leak down test and see what you get, don't expect great as you havn't seated the rings
 
805moparkid said:
well I don't think your there yet... do a leak down test and see what you get, don't expect great as you havn't seated the rings
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Not doubting your opinion but just a question. I have driven this car for 300 miles and it turns 3K doing 60mph. A lot of the driving is around the cities so i am on and off the gas. Wouldnt the rings be seated by now?
 
Oh also for the leak down test I will have to improvise and since I dont have the actual tool. What pressure should I be using to try this? I see 100lbs is popular online. Just want to make sure
 
How is your oil consumption, any blue smoke out of the exhaust? You said that you have crappy plug wires. It is possible that that plug just isn't firing and is pulling oil past the rings. Put in some good wires, new plugs and run it for a while, then see what you have.
 
d55dave said:
How is your oil consumption, any blue smoke out of the exhaust? You said that you have crappy plug wires. It is possible that that plug just isn't firing and is pulling oil past the rings. Put in some good wires, new plugs and run it for a while, then see what you have.
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Oil Consumption sucks!! Im down a quart in that 300 miles. I attributed most of it to a leaking pan gasket at the back of the engine. Although still not sure if its the pan or rear main. I need to get it on a hoist to find out.

I have noticed some smoke when Im tuning it in the garage, but Im messing with the timing and carb settings. So I really cant answer that yet. When Im driving it I dont notice any smoke.

I have a new set of plug wires, cap and rotor coming that should be here this week and the new plugs were installed today.
 
straightlinespeed said:
Not doubting your opinion but just a question. I have driven this car for 300 miles and it turns 3K doing 60mph. A lot of the driving is around the cities so i am on and off the gas. Wouldnt the rings be seated by now?
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no load at that area... you need the low rpm load to seat the rings...
 
Sorry for the late delay getting back to this. Its been hectic here.

So I finally did the leak down test and the very first time I did it I was loosing 80% of the air. I rotated the engine again just to make sure I had that cylinder in the correct spot. This time I only lost 5%, since these reading were so far off I decided to try it one more time. Same thing 5%. So just to make sure I did the #1 cylinder that was also only loosing 5%. The air was going into the oil pan since I could hear air thru the dip stick tube.

I had brand new plugs in it and decided to install new plug wires, cap and rotor. I took it for a drive and about a quarter mile down the road I stopped, and turned around. I decided to try a slight brake lock and looked in the rear view mirror, blue smoke everywhere as I was taking off! Took probably a few hundred feet for it to clear up. Then I could smell burning oil until I pulled it back in the garage. Mind you this was about a half mile drive.

Could that have been the oil in that cylinder burning off the piston? I looked and could not see any oil dripping anywhere. Well other than the leak I have at the rear pan gasket, but that doesnt drop onto the exhaust. Thoughts?
 
I'd tear it down......I know that sucks, but....I think something's seriously wrong.

Maybe check your intake gaskets....might get lucky, but I sorta doubt it.
 
cudavert said:
I'd tear it down......I know that sucks, but....I think something's seriously wrong.

Maybe check your intake gaskets....might get lucky, but I sorta doubt it.
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Only problem I have with doing that myself is that there is supposedly a 3 year warranty on it. Now the problem I have with the engine shop doing the work is I had a lot of problems with them, while they built the engine. Not to mention I dont trust them to work on the engine while its in the car. Its freshly painted and restored. Last thing I need is a bunch of scratches, dents or what not on it. Im sure the engine shop will say its not anything they did and will want to charge me for it. I dont have the equipment now to remove the engine and I actually have to have the car running because we are moving in a few weeks and need to move the car to the new house.

Its a catch 22 I guess. I did call them today and they said to get the car running again and bring it to them and they will take a look at it. What would you guys do?
 
One other thing I want to ask. After I got home with the car, shut it off and was looking for the oil leak I noticed that I always have a lot of smoke (if thats what you want to call it) coming out of the breather. Its not there while the car is running, only after I shut it off.
 
straightlinespeed said:
I actually have to have the car running because we are moving in a few weeks and need to move the car to the new house.
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Take care of this first, please.....

I understand your concern and it does sound like you may have lost that cylinder by way of a gasket or, worse, aligned rings or something broken. I'll throw in some thoughts when appropriate, but with the warranty, even though questionable, you need to take care of family business first. We'll still be here.:)
 
OldmanRick said:
Take care of this first, please.....

I understand your concern and it does sound like you may have lost that cylinder by way of a gasket or, worse, aligned rings or something broken. I'll throw in some thoughts when appropriate, but with the warranty, even though questionable, you need to take care of family business first. We'll still be here.:)
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Rick, feel free to throw them in now. Gives me time to chew on them and figure out what to do in the meantime.
 
I think you need to give the shop that built it the opportunity to make it right. The fact that they did offer to make it right is showing good faith on their part. When you check the compression, how many compression strokes did it take to get to the max PSI reading? A test of how well the rings have seated is that you should get 80% of the total on the first stroke and the total in three.
 
SGBARRACUDA said:
I think you need to give the shop that built it the opportunity to make it right. The fact that they did offer to make it right is showing good faith on their part. When you check the compression, how many compression strokes did it take to get to the max PSI reading? A test of how well the rings have seated is that you should get 80% of the total on the first stroke and the total in three.
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True they are willing to look at it, I give them that.

As for the compression test it was 3 strokes. I only looked at the gauge after I finished cranking. That cylinder was actually the highest at 155.
 
I agree with OldmanRick. Get moved, take care of your personal business, Than deal with the problem.
 
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