LS1 spitting a lot of water from exhaust

[chevy72blu]

My truck has a stock '98 F body LS1 which was reported to be around 90k miles when I bought it.

Its been in my truck for around 1000 miles and it runs terrifically. Rear O2 delete, dual straight piped into magnaflow turbo mufflers. No emissions equipment. Nothing exotic at all. Canned tune on the PCM.

This motor spits more water out of the exhaust than I have ever seen. It goes away after 10-15 minutes (though still spits tiny amounts), but during warm up this thing makes a serious puddle on the right bank and a smaller amount on the left. This is after having ran it for an hour the day prior. Outside temp is around 55* F. No visible smoke.

I've been monitoring the coolant level and I havent noticed much difference. Oil level when warm is maybe a bit high but its been a while since I looked at it. Next step is to change the oil (havent done it since before the swap) and look for milkiness. Then, obviously headgasket issues...

I know some water at start up is normal but I cant help but be concerned. Maybe I'm just used to old SBCs and this is normal? Anyone else have an LS that spits out a lot of water?

[homemade87]

My truck does the same thing . These engines are pretty efficient and at start up at 55 degrees the temp difference will create a lot of condensation . Also if you crank the truck a lot and don't drive it the mufflers will load up with water . Not enough heat in the exhaust to burn it out .

From the sounds of it I don't think you have anything to worry about .

[JNJchev77]

Mine does the same, nothing to worry about.

[chevy72blu]

Thanks for the replies. I changed the oil just to be on the safe side. Looks good with no sign of HG issues.

I did hold on to some and may send it in to blackstone labs just for curiosities sake.



[StingRay]

Gasoline is a hydrocarbon. Hydrogen and carbon. H+02 = H2O and a bunch of other stuff. If the water vapor can condense on the way out it's coming as a liquid otherwise it's vapor. When I hit the highway in the morning and it's cold the fog out of the pipe is huge. Also in cold temps intersections get heavily coated in ice from all of the exhaust water and water vapor.

It's perfectly normal.

[BR3W CITY]

Also if you only drive the thing shirt distances or infrequently, its possible to see a light "milky" look on the oil cap (only). Thats actually the condensate in the crankcase evaporating. Running an oil catch can will reduce it, but its not a problem per se.

If you wipe it off and drive it for a while. (40+ miles) and start to see it milk up again, that's when you worry about HG issues.

[foamypirate]

Originally Posted by StingRay

Also in cold temps intersections get heavily coated in ice from all of the exhaust water and water vapor.

Just wait until everyone is driving those new fangled hydrogen fuel cell cars, dumping water all over the place...

[BR3W CITY]

Originally Posted by foamypirate

Just wait until everyone is driving those new fangled hydrogen fuel cell cars, dumping water all over the place...

and then exploding! Is Ralph Nader still alive? I feel like he can write another "Unsafe At Any Speed" rofl

[crazy longhorn]

Take a look at your mufflers, as to which end hangs the lowest....drill or punch the front or rear (which ever hangs the lowest), @ the lowest part of the face. No bigger than 1/8"....this will let the water drain from the mufflers, & cause no issues with noise. The mufflers will also last longer....many factory replacement mufflers had the hole added! You can poke a coat hanger in the hole & clean it out from time to time, just to help keep the system dry Longhorn