This is crazy.... I need to do a sanity check here. I'm running the same motor from last season, no changes to the motor itself. 524WHP last season, probably 20 passes plus a couple highway pulls at that level. I was on the dyno the other day and it was puffing blue and black (I've got it tuned very rich so far, I haven't had the time to dial it in completely, so that accounts for the black).

I made a 10 mile drive yesterday, and my buddies behind me said that they had to move because the smell/smoke was hurting their eyes. I had one on the friend directly behind me on the cell phone watching the smoke to tell me when it happens, and whenever I press the gas down, it puffs blue (just cruising). Its definitely not happening in vacuum (no smoke at idle or deceleration). But whenever I step on the gas or I'm really on it, there is some blue smoke.

I did a compression test with a generic tester and a leakdown test with a MAC leakdown tester: 170 in all four and 2% in all four. (9.2:1 c/r at 6000 feet altitude). The last time I did a test 6 months ago, it was 170and 4%!!! During the leakdown, there was definitely audible leaking from the oil cap and the dipstick hole. I know that some is normal (due to the fact that piston rings actually have a gap in them). No bubbling in the radiator with the cap off, no noise out of the exhaust pipe. It sounds like I can hear a very very very tiny amount of leaking from the intake valves on all 4...its very difficult to hear. I mean its very minimal, evidenced by the 2% leakdown for the entire cylinder.

I can't see it being the guides/valve stem seals, because it doesn't smoke at deceleration/vacuum. If they intake valves are leaking, it is very small because there is still a 2% leakdown reading... I mean, I'd consider pulling the head and getting a valve job, but how much better leakdown can you get than 2% in a street motor, really? With 2%, it just doesn't seem worth it to mess with it.

So why else would it smoke blue? I was wondering about the turbo (1 year old t3/t67 with probably 2000 miles, zero shaft play and no oil coming out of the compressor side). -3 feed and -10 return (both flamenco-t's kits).

I see small puffs of smoke out of the dipstick tube hole while its idling, but I'm running an endyn breather kit, so there is no vacuum applied to the crankcase at idle. I never once blow the dipstick out of the tube, even with pulls of over 500whp at 9.5k rpms (LS crank, cp pistons, f-r rods).

The only thing I can think of is because of my piston ring gaps... I can't remember for sure, but I think I set them a 18 and 20 thousandths at build time. Perhaps the large gap size is simply causing it to smoke and I just never noticed it before.

I'm going crazy... why am I smoking blue?

 

Turbo seal on the Hotside?

 

it sounds stupid but maybe its just the turbo's return line, mine smoked blue on accel for a bit till i just nudged it around a bit, then it was fine....

 

TurboPieces5280: Do you know how could I check the seals on the hotside?

f22b2tdave: Also, can you elaboarate on what you did when you "nudged it around abit"?

 

remove the downpipe and look to see if u can see any oil in the housing...u prolly wont see wet oil but the metal will look different as u can see where the oil was at one time but u may see it wet ya never know..while u have that off..may as well look in the exhuast ports ya the requires manifold removal..to see if u can see any traces..how much blue are we talkin here? alot? does it seem to use an excessive amount of oil? GL let us know what ya find..

 

my car is doing that, what wrong with it ^^^^

 

you got a good pcv system? if not that might be you problem before i got mine my car would smoke like hell while driving hooked up a good system and it when away

 

I've got the endyn kit without a vacuum source attached (vents to atmosphere).

 

here is a few dumb questions/suggestions but something to look into.

Did you happen to take off your oil return line and make sure the hose has not broken down or something is restricting it?

Also when is the last time you changed your oil? I know my rings are on their way out. And when my oil starts getting dirty and I would assume breaking down it starts to smoke a lot. I know you said you were running rich maybe some of that gas is breaking down your oil.

just a few things to try out.

 

sounds like either valve seals (oil leaking past the valve, and into the cylinder when the valve is down)

or the turbo. you might be pushing too much oil into the turbo, (whats your oil pressure at warm when cruising the highway?)

i put an oil restrictor valve in line between my block and turbo, and a gauge between the valve and turbo. oil was a bit high even when warm, so i turned it down. at idle, my turbo see's 10 psi, when reved, it see's 35.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by underpressure02 &raquo;</TD></TR><TR><TD CLASS="quote">here is a few dumb questions/suggestions but something to look into.

Did you happen to take off your oil return line and make sure the hose has not broken down or something is restricting it?

Also when is the last time you changed your oil? I know my rings are on their way out. And when my oil starts getting dirty and I would assume breaking down it starts to smoke a lot. I know you said you were running rich maybe some of that gas is breaking down your oil.

just a few things to try out.</TD></TR></TABLE>

I should go ahead and take the return line off tonight and verify its clear.... it should be, but I'll check. I run good 'ol regular dino oil (non synthetic). It is near oil change time....

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by redzcstandardhatch &raquo;</TD></TR><TR><TD CLASS="quote">
sounds like either valve seals (oil leaking past the valve, and into the cylinder when the valve is down)
or the turbo. you might be pushing too much oil into the turbo, (whats your oil pressure at warm when cruising the highway?)

i put an oil restrictor valve in line between my block and turbo, and a gauge between the valve and turbo. oil was a bit high even when warm, so i turned it down. at idle, my turbo see's 10 psi, when reved, it see's 35. </TD></TR></TABLE>

I was under the impression that bad valve seals/guides only would cause smoking under vacuum/decelleration. Thats the opposite of when it smokes.... its fine cruising and decelerating and idling... it smokes whenever I put the gas pedal down.

I should probably do that with the oil pressure... I'm running the normal flamenco-t feed line kit.... -3AN with no restrictors. To need a restrictor, do you run -3 or -4 feed? I'm not sure what the oil pressure at the turbo is... but my engine sees 75psi while crusing at ~3k rpms.

 

i just checked all the fittings for the return, and moved the line around so it was sloped a little better, it really sounds like a turbo oil issue, definitely use a restrictor if you arent.

 

another vote for the turbo....check the charge piping for oil also...if theres oil getting in the combustion chamber it will very easily detonate and **** your motor to death

 

i would def. check oil return line. make sure its not blocked and make sure your not even the slightest overful on oil.. it will cause this problem everytime. a blocked return line will also ruin hotside seals

 

Well, this seems like a newbis queston, but I've never found a 100% positive answer. When, on a turbo car such as this, is the oil "full"? The amount of oil can fluctuate by about a quart (I'm assuming it goes to the turbo, lines, etc). depending on if I check it right after I've ran it or if I check it after its settled overnight... when should it be to the top dot?

I'll check the compressor housing for sure and post up the results

 

bump, I'll check thte return line and turbo tonight

 

Well, I got to check the cold side of the turbo... there is no oil in the compressor housing anywhere and there is no oil in the intercooler

I'll check the hotside for play and oil marks tonight

 

Well, the turbo is fine.

A leakdown test will tell me if my rings are going bad, right? Definitely the compression as well, correct? A 2% leakdown with 170psi in each cylinder (at 6000feet altitude) should mean my rings are good, correct?

 

blue smoke means oil is squeezing by somewhare into the exhaust stream to burn that color., see if your oil smells like gas, could be washing rings and burning off gas/oil mix form the rings, just enough to tint the exhaust that blueish tint.

 

I had some smoking problem on a motor I built last year. It had very good leakdown and would only smoke under high load.

To cut long, long story short, It ran a little rich which washed the cylinders and glazed them. Even after the rich condition was fixed ( which wasn't too bad) it still smoked.
This was a little a getto , but to make sure this was the poblem, I removed the head and hit the cylinders with some rough scotchbite, cleaned them out and put the head back on. It then ran like a champ, I ran straight 30 in it for 100 miles or so and smoking quit.

Even with good leak down the oil rings can still bypass oil, they have suce a tiny sealing area it doesn't take much for them to leak. I have had great luck using Wiseco rings which come with a high tension oil ring set up.
Hope this gives you something else to think about , There's not much wores than your car blowing out that deep blue cloud to ruin your day.

 

What kinf of a/f's does it take to wash out rings? I'm tuning to ~11:1 under load...

 

check to see if the PVC is clogged or the valve cover vent is plugged.

 

will a leakdwon or compression tell me about my ring seal? I'm under the impression that the combo of the 2 tests will tell you this...