chevrev

iTrader: (2)

My LS1 has these symptoms:

-when I rev the engine with the radiator cap off, the coolant pushes out
-white exhaust smoke (smells like fuel that is burning too rich, does not smell like anti-freeze) - also burns your eyes
-fair amount of water from exhaust - no visible coolant in it & no coolant smell
-pulled spark plugs and all were solid black and dry(i expected at least one to be shiny-clean or wet)


Car runs fine, oil is clean, coolant looks clean. Haven't had a chance to do any leak down or compression tests.

What do ya'll think?

z28camaro1090

hmmm .. before ripping the motor down do a pressure test on the coolant system.. You could also just have a clog. the water part doesnt make sense however unless coolant is getting in somewhere. if the plugs are fouled you prolly arent burning all the fuel so thats could be doing it to. Im not sure if its possible but if your running so rich it might be fuel ?

soundengineer

iTrader: (16)

go buy a Combustion gas Leak test kit from any auto parts store

comes with a bottle of blue fluid, a test beaker and some vacuum hose.
you put the test beaker in the fill lid of your radiator connect the vacuum hose up to any vacuum line. fill it up to the line with the fluid.
start the car, and let it idle for about 10 minutes...
if you have a head gasket problem, you will get combustion gasses coming thru the coolant...and the test fluid will turn yellow.... if you dont have a head gasket problem.. it wont change colors


other possibility is that you may have blown rings... you will get fouled plugs, and fluid out the exhaust.. if it stains your driveway, its possibly oil....
it will smell rich as hell because you will no longer be getting good combustion.
and it will seem very thin, and make you think its gas...
I just went thru that on my LS1... now you see what I upgraded to in my signature..

and when I lost my rings... I had 85psi per cylinder...way low for what it should have been.

Frog

What work if any have you done to the car recently???

Could just be an air pocket in the cooling system.....Last time I had a head gasket issue, I got small bubbles every once in a while and when they would pop you could actually see smoke coming from them and the coolant smelled like exhaust.

The water coming out of the exhaust could just be condensation especially if it was on a cool humid day when you were doing your test. Some cars produce more than others...I have seen some produce so much condensation that it comes out like turning on a water hose for a split second.

Question on the white smoke....does it dissipate after a second or two or does it linger around for about 5-10 seconds??

poltergeist 02

iTrader: (65)

your plugs will get crud built up on them in due time. your plugs won't look new after a few hundred miles or so. if they are wet then thats a bad thing, this would meen that your not burning the fuel your throwing at it or it's not burning it at all in most cases. water from the exhaust is normal. has the coolant level dropped or is it still full? your car sounds ok to me but it is best to run a pressure test to be 100% sure.

SOMbitch

iTrader: (8)

Doesn't sound like a HG to me. If you aren't losing coolant don't worry about it..

Parasoth

iTrader: (1)

x2 on cars producing more than others. Mine would produce so much I couldn't see the back of the car when I let it warm up in the morning. Changed the head gasket just because I could and the oil was fine, not milky at all.

Was so pissed. This is why you do research before you just do it.

and x2 on what everyone has said here, if you really think its a HG, try the leak test. If that's fine, try a leak down and compression check.

NBM99SS

iTrader: (33)

Fuel burning too rich will not produce white smoke. Oil or coolant makes white smoke. Usually blown head gaskets will clean the spark plugs off, not leave them black. As said get one of those combustion testers. I use them at work everyday on Northstars. They work awesome. Does the car ever overheat on you? That's usually a dead giveaway

Gonoma

iTrader: (15)

coolant coming out of your radiator when you rev it up just tells you that your water pump is working

chevrev

iTrader: (2)

Finally got some time to get back to my project.

I did a test with a combustion leak tester and the fluid stayed the same color(which indicates no exhaust in the coolant), but I lose quite a bit of coolant. I can top off the radiator, cap it and let it idle for 20 mins or so and the coolant will be down an inch or more, with no coolant on the ground.

If the coolant is externally leaking is there any other explanation than head gaskets?

The oil looks fine (no foaming, level stays the same, etc...) and the coolant looks OK. Even sitting idling in warm temps, car never overheats and coolant never boils over.

It is a freshly rebuilt engine, with less than 50 miles on it, but I did not have the heads machined or checked for flatness, so I am concerned that perhaps the heads were warped.

soundengineer

iTrader: (16)

you could just have a leaky coolant cap...
pressure at WOT or high loads will push a little out under the radiator cap seal... wont notice it unless you were on the dyno or just happened to look immediately after a hard WOT run.

get a new radiator cap.

ND400

Air lock in the cooling system.

chevrev

iTrader: (2)

I retorqued the intake manifold bolts and they had loosened up some. I would say they were about 30 in lbs, so I retorqued them to 44 and then 88. Could this have been allowing coolant to leak into the cylinders?

I also replaced the cap and I do not seem to be losing coolant anymore, but the exhaust still smells very strong. Not a sweet coolant smell, just strong.

No codes being thrown.

I recorded some data with my CP9180 and was hoping someone could tell me if these numbers look normal?

ABSLT TPS % 0.0
RPMS 716
CALC Load 3.1%
MAF FLOW GR/SE 9.50
MAP KPA 35
COOLANT 197
IAT 102
IGN ADVANCE DE 10.0
SECOND AIR ATMOS
ST FTRM1 % 2.3
LT FTRM1 % -11.6
ST FTRM2 % 3.1
LT FTRM2 % -11.6
FUEL SYS 1&2 CLSD
O2S11 V 0.210
ST FTRM11 % 3.1
O2S12 V 0.450
O2S21 V 0.240
ST FTRM % 2.3
O2S22 V 0.445


Thanks!!

1lejohn

iTrader: (9)

the intakes are dry, no water through them. I had a head develope a small pin hole that caused water to be pushed out the exhaust. That cylinders plug was cleaner then the rest.

chevrev

iTrader: (2)

pullled the plugs again. these plugs have less than 50 miles on them. Any of these plugs look like they came from a cylinder burning coolant?

chevrev

iTrader: (2)

I am pretty sure my LS1 is having issues with incomplete combustion.

The exhaust smells strong and stings your eyes, spark plugs are all dry black, O2 sensors are both dry black also. Runs ok, but takes a couple cranks to start when cold. 1st crank tries to start but stutters and dies. Seems to also have a slight hesitation on acceleration.

LS1 rebuilt with less than 50-75 miles, mostly stock. Transplanted into a 56 chevy. VATs deleted and computer tuned(I have no way of verifying how the compute is tuned). Running stock corvette manifolds w/ front O2 sensor only.




Snap shot at idle (numbers remain pretty constant at idle)
ABSLT TPS % 0.0
RPMS 716
CALC Load 3.1%
MAF FLOW GR/SE 9.50
MAP KPA 35
COOLANT 197
IAT 102
IGN ADVANCE DE 10.0
SECOND AIR ATMOS
ST FTRM1 % 2.3
LT FTRM1 % -11.6
ST FTRM2 % 3.1
LT FTRM2 % -11.6
FUEL SYS 1&2 CLSD
O2S11 V 0.210
ST FTRM11 % 3.1
O2S12 V 0.450
O2S21 V 0.240
ST FTRM % 2.3
O2S22 V 0.445

What could be causing incomplete combustion?