Smoking issues
#1
Smoking issues
I know the motor smoking issues have been beat to death, repeatedly... but thats what I'v got going on.
details: .030 over 350, new crank, new crank bearings, new piston rings filed down to stock specs, new valve seals, new head gaskets, my dad used to be a GM mechanic and he helped my meticulously rebuilt the motor checking clearances and specs
the motor is smoking and burning through oil fast, every startup it puffs a cloud of smoke, then doesn't smoke much while idling cold, smokes bad when accelerating hard, and once up to temp it smokes constantly... carries 50 psi oil pressure at idle and 65 psi under load...
my buddy thought it was running too rich, but it's set right, and it's def oil not fuel...
i'm too the point where I don't know where to go from here, neither my dad or I can figure out what the problem is
details: .030 over 350, new crank, new crank bearings, new piston rings filed down to stock specs, new valve seals, new head gaskets, my dad used to be a GM mechanic and he helped my meticulously rebuilt the motor checking clearances and specs
the motor is smoking and burning through oil fast, every startup it puffs a cloud of smoke, then doesn't smoke much while idling cold, smokes bad when accelerating hard, and once up to temp it smokes constantly... carries 50 psi oil pressure at idle and 65 psi under load...
my buddy thought it was running too rich, but it's set right, and it's def oil not fuel...
i'm too the point where I don't know where to go from here, neither my dad or I can figure out what the problem is
#4
And this indicates that the rings probably didn't seat right to the cylinder walls. How did you break in the engine? Other than the initial cam break-in run, you do NOT want to run the engine again until you're ready to take the car for a ride. For the rings to seat properly, the engine needs to be under a load; car driven or on an engine dyno. As tempting as it may be to hear the new engine, starting and running the engine in the garage for a minute or so is one of the worse things you can do to it.
#5
Oil smoke under load is a sign that the rings are not doing their job. You mentioned the ring gap is correct, but were the ring gaps staggered properly when the rings were fitted to the pistons? Were the cylinders honed properly, and if honed were the proper size pistons used? If all was done properly, then the engine was not properly broken in and the rings did not seat. Also, if the oil level in the crankcase is to high and allowing the rotating parts dip into it, there will be too much oil thrown into the cylinder bores for the rings to control it.
#6
Join Date: Nov 2007
Location: Eastern PA,
Posts: 10,352
There are a few things to mess up on rings but one of the most common I have see is people putting new rings in worn cylinder bores. A now ring can handle about .005 of out of round and will wear in during break in. With high miles or hard used motor I have seen as much as .020" of wear. In many cases these "rebuilt" motors smoke worse then they did before the new rings. The original ring wear with the cylinder over years but the new rings are just too round to seal.
I hope that is not the case for you because there is not easy fix.
I hope that is not the case for you because there is not easy fix.
#7
camaro_69 - I think you are right as to it being the rings. the cam didn't need a break-in since we didn't change it out, according to the PO it was almost new (looks new and has hydrolic (sp?) roller lifters and roller tip rockers, the whole valve train seems to be in very good shape. as for break-in, I've heard both ways, baby it, and run it hard... I ran it hard, varied speed, gear, engine RPM, accelerated and let off while in gear etc... basically drove it around the back highways that were hilly and curvy in the same manner as if I was on a race track (but safely, and not speeding excessively...)
ring gap checked and we made sure every ring gap was offset properly, pistons were proper size based off the micrometer reading on the cylinders, .030 over... but thinking back we only measured front to back on each cylinder, didn't check all around to see if cylinders were out of round... which I'm thinking could be the issue...
Luckily my wife has decided to let me buy a crate engine this winter... so i'll just drive it the way it is for now until i replace the engine... told my wife i'm at the point where i either want to buy a new engine or sell the car... she picked the new engine option
ring gap checked and we made sure every ring gap was offset properly, pistons were proper size based off the micrometer reading on the cylinders, .030 over... but thinking back we only measured front to back on each cylinder, didn't check all around to see if cylinders were out of round... which I'm thinking could be the issue...
Luckily my wife has decided to let me buy a crate engine this winter... so i'll just drive it the way it is for now until i replace the engine... told my wife i'm at the point where i either want to buy a new engine or sell the car... she picked the new engine option
#9
a little update, we bought a house and are doing some remodeling... there goes $5000, now my wife wants a different car (Subaru WRX), so no crate motor...
but i do have a 2003 GMC Savana 2500 with a 5.3 in it... first question, is that an LS1?
thinking i could drop that into the camaro since it runs amazing, burns and leaks zero oil and runs e85, but trying to figure out the logistics of the swap, will my transmission (muncie, bellhousing for early smallblock) work with the 5.3?
if what my research has come up with is right, I will need a flywheel for that motor, clutch pressure plate for that flywheel and clutch disk that works with the muncie input shaft..., but the bellhousing fits on the back of the LS?
I'm not familiar with engines past the second gen small block as far as what fits what, I'm familiar with the electronics aspect of it all so that doesn't scare me...
but i do have a 2003 GMC Savana 2500 with a 5.3 in it... first question, is that an LS1?
thinking i could drop that into the camaro since it runs amazing, burns and leaks zero oil and runs e85, but trying to figure out the logistics of the swap, will my transmission (muncie, bellhousing for early smallblock) work with the 5.3?
if what my research has come up with is right, I will need a flywheel for that motor, clutch pressure plate for that flywheel and clutch disk that works with the muncie input shaft..., but the bellhousing fits on the back of the LS?
I'm not familiar with engines past the second gen small block as far as what fits what, I'm familiar with the electronics aspect of it all so that doesn't scare me...
Thread
Thread Starter
Forum
Replies
Last Post