ok so i put together a new d15 block using a d15 bottom end from ebay "ran good when removed", and a d16 top end from the junkyard (95K miles). as soon as it got up to temperature it starts blowing white smoke like non other.

i did a compression check:
left-most cylinder: 195psi
middle-left: 190psi
middle right: 195psi
right-most: 185psi

now it had been a few months before i did the test, as i thought it was just blown rings. sometimes it wont smoke at all, and sometimes you can barely cuise without a cloud following you. it almost always smokes above 3-4000rpm, or after up shifting and letting the engine slow you down.

so what could burn that much oil? i was thinking a torn valve seal? it probably was sitting in the junkyard for a little while, and whos knows how long before that.
any other possibilites?

 

I would concur with a valve seal or guide. Get a leakdown test system to pinpoint the location of the problem.

 

thanks, what do you need to do a leakdown test? isnt that just testing the seal of the valves?

 

leakdown is when the hook a compressed air fitting to you spark plug hole.
With a gauge on a leakdown tester you would be able to see how fast the needle onteh gauge drops to detwermine if it's sealing adequately.
When an inadequate ammount of leak is found, you can listen through the oil cap hole for air passing through by ways inside the head (valve seats and guide seals).
You can also listen through the oil dip-stick hole for air passing into the the oil pan past the rings.

 

assuming its not the rings (good compression), would i be safe if i just replaced all the valve stem seals (rubber rings)? just the stem seals would be real cheap, but if i have to get the valve guides too thats a chunk more money.
the prices are below:
valve guide intake: $5.44ea
valve guide exhaust: $4.51ea
valve stem seal intake: $1.28ea
valve stem seal exhaust: $1.40ea

 

WHITE SMOKE IS NOT OIL!!!!!!!!!!!!!

BLUE SMOKE IS OIL!!!!!

WHITE SMOKE IS anti-freeze

First guess bad head gasket

 

It's an old car. If a stem seal is worn it's hard to tell why. If the guide is worn then the stem seal may wear out quicker than it should.

I've noticed (from personal experiences) that when stem seals go bad, the car will generally smoke it's worst when you are at a stop light or waiting in line at a fast food joint or something.
With bad rings the smoke seems to be there all the time, but it gets REALLY bad when the RPM goes up like on the freeway or something.

I've had an engine that warped it's cylinders. It's compression was good, the cylinder head was in great condtion, the rings were NEW, but the cylinder walls were warped. They were wavey from top to bottom. That sucked. It smoked really badly like the rings were shot.

 

i'm pretty sure that its oil smoke, it does have the white w/ blue tint, and it smells horribly of burnt oil when a cloud comes out (plus a new headgasket 3k miles ago)

the last post about the non-circular cylinder walls interests me more.

the smoke seems to be really random, sometimes i can get on it (to some extent) and it wont smoke, and other times i can barely touch the gas.

it will smoke on the highway, but only above about 80mph, and that only seems to be because of the load on the motor. if i draft behind a semi (same rpms, lower load) it stops.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by stk crx &raquo;</TD></TR><TR><TD CLASS="quote">WHITE SMOKE IS NOT OIL!!!!!!!!!!!!!
BLUE SMOKE IS OIL!!!!!
WHITE SMOKE IS anti-freeze
First guess bad head gasket</TD></TR></TABLE>

haha - I totally missed reading the color of the smoke in his post!
Good point!

To make sure though - check your fluids and see whats low!

Oh - my cylinders in the warped engine were circular/round.
They were wavey. If you put a flat edge against the cylinder wall from top to bottom is was wavey.

Anyway, seems best to have a leakdown done.

 

ya the coolant has always been the same, its the oil that i have to replenish every week.

any idea on how much a leak down will cost?

 

bump

 

Pull your spark plugs out, and tell us if they are wet (oil) fouled. If so, then I would be looking at valve seals if your compression is good.

 

ya they definetly were when i did the compression test. the actual electrode was in pretty good shape, but the head area around that looked like it got dipped in oil.

 

Oil control rings probably going bad.

 

so its probably the valve stem seals then....
what about replacing the valve stem guides?
i'd rather not just cuz of the expense.