slant six help needed, burning oil

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ducter

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My sister purchased a 63 valiant with the slant six 3 on the tree. I have been working on it for a while now. It was running when she got it but would die while coasting to a red light or stop sign etc. Took starting fluid to get it going again. Guy she got it from said it had been like that a while, said he rebuilt the carb hoping to fix it...I suppose paper clips and staples may be in carburetor rebuild kits.

I figured that to be a daily driver for her I would do a few things to it and see how it ran afterwards. I ended up replacing both the intake and exhaust manifolds, nos carburetor, fuel filter, oil and filter, plugs and wires, converted it over to electronic ignition so new distributor, rotor and cap, ballast resistor and an electric choke, bit more then I had planned but that's how out goes at times.

Now the car starts up and runs reliably but it's smoking like a train. Pretty heavy oil smoke. It was not smoking at all prior to working on it and I am kinda at a loss as to what the hell happened. I checked the timing, it's about 5 degree after, dead on tdc with the advance plugged. Yet to check compression as I just can't imagine it suddenly going from good to bad just like that.

Any guidance would be greatly appreciated.
 
Valve guide seals. *rart rart* Intake manifold might run into oil on the slant, what gasket did you use? 63'-74' you need to remove the washer on the spark plugs or they won't seat deep enough.

http://www.allpar.com/fix/spark-plug-tubes.html

Heat cycles do weird stuff to mating surfaces. Double check the snug on it.
 
Valve guide seals. *rart rart* Intake manifold might run into oil on the slant, what gasket did you use? 63'-74' you need to remove the washer on the spark plugs or they won't seat deep enough.

http://www.allpar.com/fix/spark-plug-tubes.html

Heat cycles do weird stuff to mating surfaces. Double check the snug on it.


Thanks for the response. I used felpro gaskets for the intake and exhaust manifolds. Can't seem to find the order to get an item number.

I did remove the crush washers, did not replace the spark plug tone gaskets tho, I don't think that could cause smoke? It could be the valve guide seals just odd to me it ran fine, no smoke at all then after replacing said parts smoke city. Almost smokes like rings are shot but again, was fine.
 
Do a leakdown test on the engine.
That will tell for sure if the engine is worn out.
IMHO, the timing set at TDC or 5 degrees after is way too retarded, the engine would run better with more advance.
It won't fix the smoking problem, but it would run better.
 
If it was sucking oil through the pcv system it shouldn't run very good. Then base timing at factory spec shouldn't run very good either on todays fuel.
Let us know what you find. Good luck
 
I worked with a guy who had a similar problem. he checked his hose routing and had mixed up some tubes to the carb and was sucking oil into the intake. just a thought.
 
Some ideas, will hopefully have some time this weekend to work on it some more. I would love to find something simple like the hoses to the carb but not really a way I could have done that with the hose size. Here's to hoping.
 
Check compression before deciding the engine is worn. Valve guide seals usually make smoke after idling a long time, like at red lights. When you take off, you get a puff of smoke from the oil sucked past the stems while you were sitting, then it clears up. If you get blue smoke under full throttle (but not after sitting, above), that is often bad rings.

I second the suggestion to check the PCV (cheap, maybe just change it). My 82 Aries was a horrendous mosquito fogger after sitting at a certain long red light (facing uphill), otherwise never smoked a bit. I finally found I had incorrectly installed the PCV snorkle (inside a plastic box on side of valve cover). I ASSumed, the snorkle should face down to keep oil out. I finally noticed a slot in the bottom of the elbow, figured "oil drain", must be supposed to face up (to get clean air from top of cover). Facing down, oil drops slung off the camshaft up into the snorkle tube. I finally found an article that explained what I stumbled on. I bet many of those 2.5L engines were discarded because "bad", when it was just the PCV snorkle.
 
Most likely something in what you did; the rings failing just sitting doesn't make sense.

First make sure it is oil smoke; what color is it, like a blue-ish-white, and does it smell like burnt oil? Or is it white, or a sweet smell like antifreeze? ? With that much smoke and if it IS oil, you should be able to pull the plugs and find oil on some or all plugs, you might have to run it a while.

When you do the compression test, take a reading once on each cylinder and then repeat on that cylinder. If you find any low, then put a teaspoon full of oil in the cylinder, turn it over a few times, and then take another reading on that cylinder. If you have bad rings, the oil you put in the cylinder will tend to temporaily seal the rings and give higher reading. It is not a foolproof way of finding if the rings are worn in a cylinder (if the oil rings are really bad, then the added oil will make less difference), but it's a reasonably realible test.

Check the diaphragm on the vaccum advance dashpot as you check everything, to make sure it is not open and sucking in oil that way.
 
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