I just finished replacing the head gaskets on my '93 3.8. Gasket blew between #3 and water jacket. I decided to replace both gaskets and had the heads machined. I thought I was real clean and careful in removing and replacing everything. The engine fired up no problem, but there is still heavy smoke coming from exhaust. I let the engine run until warm, but the smoke didn't let up. When I first started the engine it was not at TDC. I was assuming that since the distributor and cam were not removed this step didn't matter. I did however, hand rotate the engine and torque each pushrod when the cam was bottomed out. If anyone has any input or needs any other info please let me know. Any help would be greatly appreciated.
I'm ASSuming that it's white smoke. Probably a ****ed (cracked) head.
checked the vacuum modulator i assume? i had an 85 3.8 t-bird and that made tons of smoke. it was sucking tranny fluid into the engine.
I would hope that the machine shop that did the head work would be able to notice a crack in the head, but maybe not unless they were pressure testing it, etc.
I think it's the C5 or somethin' that uses the vac. modulator? That's one idea, but if the problem's been happening for a while you'd be real short on tranny fluid after a while.
Both heads were pressure tested and checked out okay. That was my fear, either a cracked block/head. The car is parked a friend's house. I'll check the transmisson thing and check if there is any water in the oil also tomorrow. Could the head still be cracked if it passed a pressure test? Thanks for the advice.
Run the car for an hour or two.
I've done headgaskets before where the car had so much coolant in the exaust that it took an hour or so too burn it all off.
If there is no evidence of overheating or coolant in the oil then it's just coolant in your exaust.
Werd. Take the car for a drive of several miles (keeping close eye on the gauges). You'd be surprised how much coolant gets into the exhaust and how long it takes to burn it out.
I let it idle for about a hour and everything burned out. Nothing but clear exhaust now. Thanks for the advice. That's a big relief.
Been there done that lol. Cracked my heads 4 years ago on my old bird.
+2..
Thats what I had to do after I popped BOTh my HGs in my old 85's 3.8L:burnout:
i didnt know the mn12 cars could be had with a c5 trans?
its interesting you mention the smoking thing though, ill have to check mine as its been smoking a bit lately i dont think its weather related. not bad or anything but never stops even when warm. i dont think its the headgasket but no big deal if it is(could be the intake manifold one though) :wtf:
They couldn't... No trannys were used that had a modulator valve...