VY LS1 Coolant leak in exhaust

[NickGNB]

Hi everyone,

I've got an 02 VY SS Sedan (GenIII LS1) that leaks a lot of coolant. I was looking over the car and found coolant leaking out the join between the flange on the drivers side headers and the exhaust/pipe to cat. The car chews through litres of coolant within weeks, but never seems to lose a drop of oil. It throw white smoke out the exhaust, as well as a fair amount of what seems to be water...

Has anyone had coolant leak into their exhaust headers and if so what was the cause? I find it strange that the coolant leaks but no oil seems to.

Any ideas or experience?

Photo below of the merge between the headers and exhaust that leaks. Annoyingly not much coolant showing in this shot.

 

[uniacidz]

Heater tap is on that side, prob leaking/spraying onto cats and headers when pressurized hence the discovery

As for white smoke, could be condensation upon normal cold startup
Does it go away once warmed up?

 

[NickGNB]

Would the heater tap leaking cause it to leak out of that joint? I can actually see it ooze out of the joint when running, especially on start up.

It doesn't seem to go away no, admittedly the car has only done short trips in recent weeks (and off the road for a while prior) but even after driving for 15 - 20 minutes it still blows the white smoke. I can chuck a drip tray under the exhaust and pickup a fair bit of water. When starting the engine for the first time in a while the same white smoke came off that exhaust/headers joint through the engine bay, had me pretty worried until I saw it was just the coolant leaking out that join. Now just worried about why coolant is making it's way into the exhaust...

I have no idea if it's relevant but the oil doesn't seem cloudy or anything so I don't think the coolant has met the oil in the engine.

 

[uniacidz]

Thats the case, then possible headgasket leak

Compression test, check spark plug tips etc etc

 

[XUV]

Raw coolant on hot surface will produce a white smoke, run it into your exhaust headers and you get a great smoke screen

 

[NickGNB]

Yea fair enough, I think the heads are in need of some attention. I'm considering dropping the engine and getting the heads done, replacing the lifters to kill off that annoying LS1 ticking noise and putting a new oil pump on. I imagine this could get expensive and/or time consuming though. I'm quite keen to get an oil pressure gauge installed so I can see what's going on in there. The car had a habit of throwing oil warning in the past, it seems to have stopped for the moment but I would love to know what's going on in there...

Yea good to know that that is what's causing the smoke. Still not fun to look at though .

 

[south123]

I think it's more than likely your inlet manifold gasket is shot, it will leak into the cylinders then when you start the engine it will pump out through the exhaust and turn to white smoke as the exhaust heats up.

 

[NickGNB]

Sounds like a new set of gaskets all round really. Anyone replaced the lifters in their LS1 and have recommendations for something that doesn't make that bloody ticking noise?

 

[Tonner Matt]

I think it's more than likely your inlet manifold gasket is shot, it will leak into the cylinders then when you start the engine it will pump out through the exhaust and turn to white smoke as the exhaust heats up.

An LS1 won't leak coolant from the inlet manifold as coolant doesn't travel through the inlet manifold

It will most likely be a head gasket issue if you are getting a continuous stream of white smoke when driving
It wouldn't hurt to do a compression check also as already mentioned
Do you get bubbles in the header tank when the car is running, this is a sign of compression making it into your cooling system and will also confirm that you have a blown head gasket

 

[NickGNB]

Fair enough, I haven't noticed bubbles in the tank, but will take a look when I next run the car. The white smoke is pretty consistent so I'm thinking it does sound like a head gasket.