Thread: Smoking a WOT

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Hey guys, hope some one will have some insite for me on this one.
I have a rebuilt 305cid in my 1980 camaro, and I am getting thick white smoke at WOT. It is driving me crazy because I have rebuilt the motor, it has new bottom end, including pistons, rings and bearings. I also have new- rebuilt mild-performance heads on it.
I have not checked compression yet, I have just moved to NC so I have to get my garage situated, but I did check the plugs and I have oild buring on #3 and #6 cylinders.
The old thing I can think of is I did not have the block checked, bored or honed. I honed them myself with a drill and I honing stone. My thinking is that maybe the cylinders are out of round and the oil is comminf up past the rings, or may be the valves are not closing all the way and it is being sucked through the valve seals. I am not leaning on the the vale seal, since the heads were rebuilt by a repeital machine shop and the only have about 700 miles on the heads, but the bottom end has about 3000 on it.
Well if any one else has any other ideas that would helpp I would appreciate it. I am thinking about finding a 350cid block to rebuild for it, doing it right which haveing it checked out and bored by a machine shop, I just hate to have to go through all of it again.
Thanks, ken

i'll try too calm your nerves a little , white smoke means your eating some water, its not oil. if you screwed up the honeing in the cyl or anything to do with the rings you would be shooting out blue smoke. Because it happens at wot i would guess its because for one reason or another your head gaskets are leaking under hard load. i would try retourquing the heads first, and then see what happens. did you re-tap all the head bolt holes in the block before you put the heads on ?

Ya, that is true, I forgot that it would have been blue, not white. I did chase the threads, so I can try re touquing the heads again and see. Thanks

Some may disagree but this is a top and bottom to some head gaskets. Also you may have a worped head letting water into the cylinders. Is there water or brown foam in the oil pan? I do know that white smoke does mean water in the cylinder and there is only one way in to them, either a crack or a blown gasket. Just a guess, I hope that you get it figured out, I know what it is like to go through all that work and have it not run right. Good luck.

Anywhere for water to get into the intake manifold and route to cylinders #3 and #6. From what you're saying they shouldn't be burning oil. Maybe they're the steamers?

I thought about water or oil getting in through the intake, maybe the gasket, but I have replaced the intake gasket already cause oh this problem. One thing though, I am lossing oil, and the plugs were oil sooked, wet, black. I am going to do a compression check today, and I have a coolent system preasure tested also, so I am going to check that out as well and I will let you know what I find.

From my experience when you are getting water into a cylinder it's usually clean, will be the cleanest cylinder in your engine.
From the looks of your plugs by your description they aren't firing at all, might be fouled out, try putting some new ones in them dead holes.

One word from a ford man, chevy. HE! HE! I would do like 53 Chevy said, If that don' t work take the heads off and check the gasgets to see if you can tell if the water getting in to the cylinders there. Maybe put a striat edge against the head to see if it's warped, check the block decks too.



~ Vegas ~

sounds good, thanks guys.
I checked the compression and I am ranging from 105psi to 120 psi, and the cyl in question were not the lowest.
I have to pull the headers off to get to all the bolts to re-touque the heads. I will keep everyone posted on what I find out. Thanks again.

I have had bad head gaskets and the plugs came out clean, but what is throwing me of f is that the plugs came out wet/ black, which usualy means oil. I am going to try some of your sujestions, re-touque the heade, replace the plugs and see what happens. I will keep you posted.

Originally posted by zort86
sounds good, thanks guys.
I checked the compression and I am ranging from 105psi to 120 psi, and the cyl in question were not the lowest.
I have to pull the headers off to get to all the bolts to re-touque the heads. I will keep everyone posted on what I find out. Thanks again.

i hate to say this but 120 psi compression isnt very good let alone 105 . with a fresh re ringed motor you should be at 150 easy

Ya, I was thinking the same thing. unless it is leaking out the head gasket, there may be something else wrong. This is a 305cid block, it hasn't been bored, at least not since I owned it, and I have had it for about 6 years. The last owner I think just had a cam and intake put on, but nothing else, maybe rings and bearing, but that may be pushing it. It looked to clean to be untoched for an 1980, but not clean enough to be completley rebuilt. I am going to try touquing the heads and new plugs.
I am going to get the block from my father and have it cleaned uo and bored out. I want to get a 383cid kit for it.
I was planing on doing that from the begining, but I wanted to drive it this year with this motor in it so I could take my time and do the 383 right.
Well thanks guys, anything else I should look for to get this thing to stop smoking?

as stated with dennys bulb chart you may want to look at your plan A route with starting over new with a 350. how did you hone the cyl ? was it with a ball hone going up and down the length of the cyl for 30 sec to a minute while spraying solvent in from time to time, and are you sure none of the rings got broke during assembly or put on upside down?

Hahah, Touche Denny!

I vote for messed up headgaskets/torque.