Head Gasket job

**davidlb512** · 12-23-2009, 11:52 PM

Just finished a head gasket job on my '95 3.4L Firebird. Here's the story, I had the oil changed, used Castrol GTX 10w30, Lucas Oil Stabilizer, and a Fram filter. Two days later was the first time i drove it decent distance since the oil change (over 10 miles). I stopped at a red light, and when i pressed the gas, a puff of smoke came from the exhaust, and there was a cough sound from the engine, and the temp was going up, but not real fast. I pulled over in a McDonald's parking lot, thankfully i was hungry too, haha. I popped the hood, and the coolant was about 2 gallons low, and there was a strong smell of gas in the oil too. Never had the gas in the oil problem before. Well, got the head job finished, and the sick chicken is well again! But haven't changed the oil yet. Drove it for the first time tonight, and oil is now leaking from the rear main seal. Could that be cause by the oil be diluted with gas, and it's seeping past the seal? And could blowing a head gasket cause gas to mix with the oil like that? Hoping i don't have another issue.

**DaddySS** · 12-24-2009, 03:14 AM

A blown headgasket will not cause gas in the oil. Track down the fuel problem asap - too much gas in the cylinders and gas in the oil are both bad things. It would take a substantial amount of gas to cause a rear seal leak. If it wasn't leaking before, look more closely, it's probably coming from the top of the engine around your head job (intake manifold) etc.

**sunsetorangess** · 12-24-2009, 04:34 AM

Like said above, if it wasnt leaking befor you replaced the head gaskets then chances are its not the rear main.
Gas in the oil is bad. I would pull the plugs or valve covers and ensure none of your rockers have come loose.
Im also assuming you did torque the heads down correct?
J

**Smittro** · 12-24-2009, 06:32 AM

Prolly not your rear seal. Check the oil pump drive @ the back of the block and to the left if you're facing the front of the engine. That o-ring is notorious for leaking and leaking badly. Gm has an updated version of the o-ring because of the issue. If you local parts guy does'nt know what to look for, tell him you want the oil pump drive o-ring for the LQ1(DHOC) 3.4L..

Next, do a presure test @ the rail and watch the gage you be looking for a bleed off. Could possibly be the presure reg too. All are a PITA to fix but doable in a few hours.. Gas in your oil is bad news change it asap..

**davidlb512** · 12-28-2009, 09:59 AM

Found the culprit for the oil leak, and boy do i feel like a dumbass! Haha. Got the FelPro head gasket kit for the car, and there was one small piece of gasket missing where the lower intake meets the block. There were 2 seperate pieces of gasket to between the heads and lower intake, but don't ask me why it didn't register with me that there should be a gasket for the block and intake. Anyway, tore everything back down, and got it taken care to. No issues, just an idiotic mistake. Thanks for the advice tho guys. And gas is no longer mixing with the oil either. Changed the oil, and have a couple hundred miles since, and no fuel in the oil. The only thing that i can think of that could've cause it, is possibly when i blew the head gasket. It never done it before, and hasn't done it since. I'm gonna keep an eye, and nose, out for it on a regular basis tho.