overheat / white smoke

[Commando14]

so...the car has been running like a top. till tonite...

didn't pop on the fans after coming to a stoplight, and meeting someone in a parking lot, for.....~5-10minutes TOP. Noticed an odd exhaust note leaving the lot, then noticed the water temp gauge up at ~230-240 degrees. Threw on both fans, the temp instantly began coming down. We stopped at a gas station, ~1-2 min later. Temps were down to normal, shut it down with the fans still going. Noticed coolant on my fender/hood. Popped the hood, the overflow tank was full and the top popped off, thus the coolant on the fender. It began smoking, white non-foul smelling smoke, at idle. not billowing, or super thick, but it was puffing some none-the-less. Still runs pretty well. Still sounds odd at idle/decel. Kind of similar to a misfire burble.

Checked the chargepipes, theyre ok. Catchcan isnt overfilled or full. Oil isnt milky. Pulled the plugs, cyl.5 was wet. Didnt smell like oil/fuel. Cranked it, plugless (ign and fuel disabled) to clear it out. Let it cool down. Put it back together, still a light, white smoke at idle, and after revving. Took for two quick pulls, to try and maybe clear out any left-over whatever. Didn't help. Still pulls strong, spun in first and second. Didnt get too hot, either. But boost only seemed to get to ~18, not 20 like before, though that might just have been cuz of where I did the pull. There is condensation in the exhaust too. Popped off the coolant overflow cap the first run, second it stayed on but there was pressure in the overflow. It was bulging, the plastic cap.

Im thinking the headgasket is leaking, not blown, on cyl 5... :/ advice? Something else to check?

[Darius]

Sounds like the gasket is blown. Do a compression test. If you replace the gasket, make sure to mill the head because it could be warped.

[Commando14]

Any recommendations on what to get? It's making 385whp. Would a stock be fine or go with a cometic?

[Darius]

Stock unless you want to take it all apart to get the block milled too. Take it from me, do NOT put any metal head gasket on any engine without machining the head and block surfaces first. I tried to cut corners originally and I ended up taking it out again and again. For 385 hp, stock gasket is fine. If you want to upgrade things, get ARP head studs and nuts.

[Coolwhip]

+1 to Resurface head, Stock head gasket and ARP Head Studs. Done.

[Commando14]

You'll be getting an order this weekend coolwhip. Thanks you two.

[Commando14]

Just an update here. Put in a new stock headgasket + arp studs last night. It started right up, Cept it sounds like a diesel, so I immediately shut it down. The oil is milky too, now. Could it be from the oil? I'm going to change that reguardless. Or maybe timing? I indexed the cam gears to the timing cover to make sure they stayed properly aligned. Maybe it jumped a tooth? Any ideas? :/ thanks guys

[Darius]

When you changed the gasket, did you change the oil too? If not, your oil could have had water in it from the head gasket popping. It probably sounds like a diesel because the valve lifters haven't primed up and the cam lobes are slapping against the buckets. Change the oil again and make sure that oil doesn't foul too. If it gets milky right away again, you have bigger problems.

If you DID change it and now you have coolant in the oil, that's not good.

[Commando14]

Didn't change the oil yet. Been at work all day, haven't got to. It's the original oil from the old headgasket.

[Commando14]

so, I changed the oil. It was milky as helllll. Let it drain till it couldnt drain no more. Literally. New filter and fresh oil, still making noise, doesnt seem quite as bad, but still bad. Took off timing cover, jogged it with no spark plugs as close to TDC as I could, matching it up with the first timing mark on the harmonic balancer. It seeeemed maybe the intake side was 1 tooth off? It was super hard to tell, so I said whatever, and pulled the belt off again, lined everything up dead on, and put it back together. Cranked with no fuel, plugs, etc, again, and rechecked, still dead on. So i put all that back together, and started it, still making noise.

It starts up instantly, like a champ, no hesitation or anything, everytime. A tiny bit of blip on the throttle (maybe up to 1500, max) it doesnt hesitate or studder. No noticable smoke from the exhaust. My mechanic friend who was helping me listened to it with a feeler and said it really sounds like valvetrain noise, the lifters. The oil is still milky, but not as bad as it was before.

Im thinking it was a big mistake to start it without changing the original oil, and Ill have to flush the new oil out again, and maybe one more time to get all of the milky junk out. I dunno, its frustrating as hell.