1994 Pontiac Firebird Problem with Head Gasket Repair

1994 PONTIAC FIREBIRD
165,000 MILES • 6 CYL • 2WD • AUTOMATIC
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ROUGHRIDERGUY
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We replaced the head gasket, everything is put back right, and when we go to start the car all we get is the car cranking (spinning the belts) but nothing else. It'll back fire sometimes, but not too often. We know we have spark, we know there's fuel (maybe too much fuel seeing as the plugs and even o2 sensor are wet to the touch?), we don't know we have compression though. We didn't touch the timming.
Any suggestions on what we should try? And can we do a compression check with accurate readings with a cold engine?

Thanks,
Stuck in Columbus
Feb 28, 2008 at 7:32 PM
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FLEXY5
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If I can ask, did you replace the head gasket because the engine overheated? It sounds like it doesn't have compression. Either the timing has jumped or there is significant damage to the pistons. That would have been obvious, though, with the heads off. I would guess on it being a timing issue. You can do a compression test on a cold engine. You may get slightly lower readings, but not by much. Test each cylinder dry and wet (by wet I mean add a couple drops of motor oil into the spark plug port before the test). This will give you two different readings. Make sure you post both sets of readings for every cylinder and we can go from there.
Feb 28, 2008 at 11:14 PM
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2CARPRO JACK
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Those GM 6 cyl's will hold the valves open when you reassemble them, dont worry they are just stubborn about the lifters bleeding back down..let it set, then crank it for a second or two, then let it set again. The cyl's will come back. If you hold the throttle to the floor, sometimes they will start and the cyl's will come back.This one does have non-adjustable valvetrain? what size engine?
Feb 29, 2008 at 7:42 AM
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ROUGHRIDERGUY
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Well, we decided to change the head gasket because when my buddy was driving the car he said he heard a noise (I don't know what kind) but then the car started puffing white smoke out the back a lot! He said he only drove it for 2-3 minutes until he could stop and the repair shop said it was a head gasket. Changing the gasket we didn't notice the pistons in bad shape, although they did have a lot of crud and even some antifreeze sitting in some of the cylinders. In fact the whole intake system had a lot of crud buildup. It's a 3.6L and as I said we didn't touch anything with the timing, so seeing as it was running before (badly) it should still run after right? I've heard something about the lifters needing to be bled down, but do they do that by themselfs? We've tried cranking the car 7-10 times thoughout the day yesterday, with and without the throttle open and still havn't got any different results. I don't know what you mean when you asked if it had a non-adjustable valvetrain, we didn't adjust or remove any of the valves though.
Feb 29, 2008 at 10:07 AM
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2CARPRO JACK
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Did you remove the rocker arms? GM doesnt have a 3.6........ 3.4 or 3.8. Be patient, if the lifters are the problem, they will eventually bleed down
Feb 29, 2008 at 10:14 AM
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ROUGHRIDERGUY
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Yes, we did remove the rocker arms. And your right, it's the 3.4L, I was thinking of something else.
Feb 29, 2008 at 10:19 AM
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2CARPRO JACK
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Are the pushrods in the correct spots? there are 2 different lengths, long are for the exhaust short are intake
Feb 29, 2008 at 11:21 AM
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ROUGHRIDERGUY
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Yes, we were very careful to make sure everything went back in the exact spot it came out from. We tried starting the car again today and the same thing. Cranks, but doesn't start. The lifters your talking about, do they bleed themself only when the car is cranking, or over time? It's been a good 24 hrs since we first started the car, and over 10 days now since the heads and lifters were installed. And what do you think about the cylinders being so wet with fuel, even the o2 sensors are wet? Could that be front the lifters not being bled?
Feb 29, 2008 at 12:28 PM
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MERLIN2021
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My suggestion, remove valve cover, see if rockers are moving up and down, then change the oil and spark plugs for dry ones...you are completly gas fouled by now...all that gas has washed the cylinder walls with gas and you have lost compression...new oil, filter, and plugs...BTW you did have the head checked out at the machine shop right? And you did both heads over?
Feb 29, 2008 at 12:35 PM