Thread: Can't Stop Smoking!

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Well, I have to turn to the experts for this question...I'm at a complete loss. I just finished rebuilding a 327. Deck milled 20, bored 30, torque plate honed, forged flat top pistons, ductile iron rings with moly facing, aluminum heads, small b&M blower. This thing smokes like crazy. If I start it up in the garage, you'd think the house was burning down. It puts out soooooo much white smoke it's rediculous. I have checked everything I can think of and still can't find the problem. The heads were redone with bronze guides, new valves, teflon mushroom oil seals. It idles fine, runs strong, but just smokes insanely. No water is being lost nor is oil getting into the radiator. I pulled off the intake to see if it was possibly sucking oil from the lifter valley. Nope...good seal on the gaskets. Plus, it's every cylinder. When I pull the plugs, they are all black and oil coated. I know the PCV was sucking some oil, but I disconnected it and plugged the vacuum line and still got smoke. I did a compression test...all cylinders at 165 lbs. Did a leak down test...all cylinders at 94% (kinda low but not so bad it would create this much smoke). When I pulled the intake to check the gaskets, I noticed the whole inside of the intake and runners on the heads were coated with oil. Also, the rotors on the blower are also coated with oil. I cleaned everything and put it back together to find the same smoking problem.

I am so frustrated because I think the cylinders were honed wrong for the type of rings I had and they never seated. I'm not sure if the leakdown test is too bad that it would create this much smoke, but I guess it's possible. The only other thing I can think of is that it is being sucked past the valves. I can't immagine this to be the case since I'm using teflon seals, but hey, who knows.

Anyone run into this problem before? Thanks for any help/advice you can give.

I'm not blond, but I take a stab at it..................
Got any PCV lines runnin' from the valve cover to the carb. that could be suckin' oil ? That johnson rod scenario is very intriguing also.

BTW: Rather simple thing, but were the ring gaps staggered from 1 ring to the next when assembled ???

Yip, I know I was sucking oil through the PCV, but I took the intake and blower off and cleaned out the oil, then reinstalled. I left the PCV out and ran it for about an hour and got the same problem.

Did stagger the rings (I explicitly made sure). Plus, each was file fit specifically to each cylinder and installed in the correct groove and the correct side facing up. I would think if it were the rings, the compression and leak down would have been muuuuuuch worse to loose this much oil.

The strange thing is that it is both sides causing the problem. If it were one or two cylinders bad, I would say okay, broken ring or a crack...but ALL cylinders? And again, the compression and leakdown results don't indicate a problem on any particular cylinder.

There's no doubt it's oil burning. I've lost 4 quarts in 200 miles. No water is lost and the water is clean as can be. So is the oil (when it's not burned off). Maybe the smoke is blue, but it's so obvious that it's oil burning. No idea what Streets is talking about with the oil line to the johnson bearings. Maybe that's one of those copper magnet kind of things. What's an oil line got to do with oil in the cylinders? The blower is not oiled...it's self contained (if that's what you meant by oil line)...and it's not leaking oil...I checked. And nope, not an 83 vette.

Anyone got any armor piercing bullets?

Originally posted by tjpoc


Anyone got any armor piercing bullets?

A 7.5 should go right through that block and out the trans, don't think you'll need ARP's.......... ? I could be wrong, tho maybe some one will inlighten us both ?

"just trying to help "

Aluminum heads eh?

I know you probably have this covered but.....

Is it possible that the heads may be warped?
A friends uncle installed used aluminum heads that happened to be warped, and he had unexplanable problems too because it wasn't showing any "head gasket" symptoms either.

Another thing to consider is that you do have a boosted engine.....So your intake tract is pressurized instead of under vacuum like N/A engines. What this means is that a small leak will be magnified because its under a lot more pressure - So if theres a little too much clearance between the ring and wall, your whole block is pressurized and it'll force an escape somewhere... Maybe past the new valve guides?
Do you have just an open vent on the other valve cover?

Sorry if this is all redundant garbage, just trying to help.

Thanks Blue, I had not considered the warped head thing. That's certainly a possibility as they are used. I did disassemble them to replace the springs and I checked them over by eye, but I did not specifically check for straightness. Wouldn't you think I'd be getting oil in the water or vice versa? Also, wouldn't you expect to see some strange readings on the pressure and leak down tests? And man, the chance of both heads being bad? But hey, I'm willing to entertain any possibility at this point as long as I don't have to tear down the bottom end.

There seems to be two schools of thought from the local engine builders about boosted engines...one is that there is so much crankcase pressure it is forcing oil up into the cylinders past the rings. The second is as you said, it is being blown past the seals and down the valve guides. If that's the case, what can I do? Add a vacuum pump or multiple PCV's to reduce the pressure? Or if I add a vacuum pump, could I just pull vacuum on the crankcase without a PCV to really get the pressure out? I am currently using a PCV on one valve cover and the other cover is vented with a basic push in type breather.

Another common theme is that the rings just haven't seated yet. Many people have said give it 500 miles or so. I just can't immagine that to be the case after using 4 quarts of oil in 200 miles and there doesn't seem to be any change in the oil consumption. The oil is definately going out the exhaust...the question is where is it coming from? Errrrgggghhhhh!!! Moly rings not seating? Anyone have experience with moly rings allowing this much blow-by?

My next step is to pull the heads and have them pressure tested. Also, while they're off, I can check for scored cylinders. I'd hate to re-ring it just to find out that it was a leak in the top end. The strange thing is that it seems to be the worst at idle (when there is the most vacuum). If I drive it and come to a stop sign or if I gas it at idle, look out man, fogger city. But when I'm driving it while keeping it in the R's and gas it, it doesn't seem to leave a cloud of smoke. Although hard to tell 'cause I'm moving and the smoke is dissipating into the air.

I'm open to any ideas....

Well, I don't know that I have the answer for you; but, when I first stuck the crate motor in my 55, I thought I was going to have to invest in a refinery to keep the oil in it. It has been a few years now (over 10) but I don't remember it taking 4 quarts after 200 miles while the rings seated!! What I do remember doing though was replacing the pcv valve and putting vented caps on both valve covers to try to get as much ventilation as possible to the crankcase. That seemed to make it bearable until the rings finally seated.

Lotso luck to ya,
Firechicken

Originally posted by Streets
hehehe White smoke is water, Blue smoke is oil.. Black smoke is H20 in the fuel.. Green smoke is what rises off the swamp at nite..
'n I think Techie wuz right when he said what he said about "Tests"...

So lemme get this right....if it's water in there then it's white smoke....and if it's H2O then it's Black....Now I gotta ask, what if it's Hydrogen Di-Oxide? Is it Gray?.....

Awww I'm jus messin' wit yeh.

Cheers,
Firechicken

water in a radiator homie.... h2o in your gas....
jus messin wit ya

OK I'll add my 10 cents worth, Check to see if it's the engine or blower . Take off blower put on naturally aspirated carb and manifold. If it still smokes its an engine problem if it does'nt it's the blower. Sorry it's not an exact solution but it'll get youinto the right ballpark.

Might not be much help, as I'm fairly new to engine building and have my own problems.
If it's anything concernig the integrity of the blower, I'm of no help, haven't got a clue about those things.
My suggestion: pull out the spark plugs, if they are very oily, then it will probably be a top end problem. If they are not very oily, then it might be bottom end (if oil comes from below it won't reach your plugs, if it's running out of your valveguides it will cover the plugs first). If they're clean, it can almost only be one problem, depending on what intake you're using: if it has an exhaust-gas connection between the left and right head, it might be the intake seal near those places (they get hottest and will suck a good amount of oil, because where it's hottest the oil will be thinnest).
Are you quite sure your not having the problem on only one cylinder each side. Those intake manifolds are sometimes buggers to get properly sealed. If the outer seal is OK, the inner one (that seals off the oil in the lifter valley) might be blown or faulty, with a blower the pressure can sometimes press out a lose seal. And get rid of those rubber end-seals at the front and back end of your intake. They tend to slip and a good dose of RTV-type silicone will work much better.
But the first thing I would do is take off your manifold again and see if it's oily in the intake runners again. If it is, it's probably nothing I can help you with. If the runners are clean, see above.
Hope I've been some help,
MadMax

Originally posted by tjpoc
Also, the rotors on the blower are also coated with oil.

Guess I'll throw in my 2cents, your rings aren't doing thier job, the Total Seal gapless would be my answer but since you don't want to tear it down you could try a crankcase evacuation system, not made for street use but.........


http://store.summitracing.com/partde...rt=MOR%2D25900

Viking beat me to it. Couple guys running blowers on the street around have had trouble with excesive crankcase pressure and have gone to the evacuation system shown with good results. The angled pipes are welded into the headers and exhaust flow creates a vacuum the pulls the pressure out of the crankcase. The round fixtures are one way valves that protect from back fires blowing back into the crankcase.

My other suggestion is to call B&M, it's their blower, I bet they have trouble shot a few systems before.

Pat

Yeah, youre probably right about the heads - It is a longshot that both are warped.....BUT, what about the lower intake? Specifically where it mates to the heads. If you have the top-end all apart, might as well check all surfaces for straightness.

For the PCV, I'm not sure what you could use. One thing for sure is that boosted engines need SPECIFIC types of ventilation for the crankcase - If you run a regular PCV you might end up getting oil "shot" into the intake through the PCV when your block is pressurized (under boost). Also, running an open breather might cause your engine compartment to be covered in a film of oil because of the pressurized block thing, but this is more of a nuisance than a serious concern.

As for the rings, Ive never heard of that much consumption while seating. I don't know who your machinist is, but if the cylinder wasn't bored perfectly "square" then your rings won't seat properly at all. Moly rings especially need a perfectly bored surface as opposed to regular cast rings.

Gapless rings aren't really an option, theyre only good on low performance applications, on high compression engines - and specifically boosted engines - you get ring flutter...Not good at all.

The only boosted car Ive ever owned is my current factory turbo car, so I'll try and relate.
For block pressure, well, it has enough pressure build-up in the block that the rubber-sealed dipstick pops out.... And this is all how it was engineered from the factory, it runs as perfect as it should.
The PCV is specific, it has a valve in it that (supposed to) avoids any oil going past it, and also avoids the tendancy for oil to shoot past it when you suddenly come off boost. It leads into the intake tube (air cleaner box) which supplies the vaccuum, which still manages to gets some oil in it, but still works as good as one can expect.

Thing is its acceptale for boosted cars to have some oil burning and some blow-by, but yours is too excesive (Thank you Captain Obvious).

I think your best bet would be to either call someone who specifically builds roots style SC V8's, or try and get a technical book on SCing.

For the summer, I know this goes against hot-rodding, but maybe just put a regular intake and carb on so you can cruise around and enjoy whats left of summer...

Sorry I couldn't be more help

The common theme seems to point to the rings not seating (or too much crankcase pressure). I've heard the idea of evacuating the pressure out of the crankcase by quite a few people, soooo, I'm led to believe this is probably the place to start. I may go ahead the try a regular intake to see if a naturally aspurated setup changes anything. I'll also check those intake gaskets for proper sealing again (although the original "crush" looked good around the lip...the heads don't have an exhaust pass through). And if I can find an old vacuum pump, I may just try that to get the crankcase pressure down...at least to see if is actually blow by. I've heard of the gapless rings, but I'm not sure that would prevent this much oil from being lost. If it's really blow-by, then I've got to do something to get those rings seated.

Anyone got a vacuum pump setup for sale?

By the way, thanks for all of your advice and suggestions! Any other opinions or experience is welcome.

tj