bbc motor smoking
#22
Re: bbc motor smoking
Originally Posted by ssmonte70
i did a compression test and all cyl have 175, new valve seals new motor, changed intake gasket, put new mufflers, still smokes,
#23
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Re: bbc motor smoking
Originally Posted by ssmonte70
i did a compression test and all cyl have 175, new valve seals new motor, changed intake gasket, put new mufflers, still smokes,
Or low tension oil rings?
Or sucking oil from the intake via a vacuum leak? Are the intake gaskets oil wet at the bottom?
There's a limited number of places you can introduce oil into the cylinder above the piston.
Rings, valve seals, intake gaskets, vacuum line via carb from valve cover (pcv) or transmission...
If it's not sucking trans fluid via a vacuum line from the trans to the carb, and the intake gaskets aren't wet at the bottom, and it has new valve seals (which I don't run any and my junk don't smoke), then the only other way I can think of would be the rings installed upside down.
#24
Re: bbc motor smoking
Originally Posted by OneBadGMC
Originally Posted by ssmonte70
i did a compression test and all cyl have 175, new valve seals new motor, changed intake gasket, put new mufflers, still smokes,
Or low tension oil rings?
Or sucking oil from the intake via a vacuum leak? Are the intake gaskets oil wet at the bottom?
There's a limited number of places you can introduce oil into the cylinder above the piston.
Rings, valve seals, intake gaskets, vacuum line via carb from valve cover (pcv) or transmission...
If it's not sucking trans fluid via a vacuum line from the trans to the carb, and the intake gaskets aren't wet at the bottom, and it has new valve seals (which I don't run any and my junk don't smoke), then the only other way I can think of would be the rings installed upside down.
#25
Oil burning
Have you tried draining the fuel system? Maybe there is oil in the fuel. Outside of the things ONEBADGMC stated there isn't anything left. I'm inclined to belive the rings are upside down. Are all the plugs showing signs of oil or just a few?
#26
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Re: bbc motor smoking
Originally Posted by DirkaDirka
I didnt even know you could put rings on upside down. I thought they could go any way. I learned something today. :lol: :lol:
There's a picture about mid way down on that page showing the different ring designs and the direction they are to be installed in the bore.
#28
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bbc motor smoking
no oil in the fuel, drain the oil and there was a little fuel in the oil,i dont believe with 0 leak down and 175 compression that the rings are in upside down on both sides,10.5 pump gas motor, is it possible that the carb may be to big, 1095 king demon , thanks
#29
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Re: bbc motor smoking
Originally Posted by ssmonte70
no oil in the fuel, drain the oil and there was a little fuel in the oil,i dont believe with 0 leak down and 175 compression that the rings are in upside down on both sides,10.5 pump gas motor, is it possible that the carb may be to big, 1095 king demon , thanks
Anytime there's enough gasoline to see it in the oil the carb is washing the cylinders dry and it's not sealing properly.
No offense, but I find it hard to believe it's 0% leakdown. A really good motor is going to leak 6-8% when hot. If you can get a cold leak of 10-12%, the rings should be fine.
If the carb is washing the cylinders down though, it's gonna smoke.
Doubt the carb is too big for it to idle. Lean out the idle mixture screws and see if it stops smoking.