Depends entirely on the year and fuel system. You did not provide that info.
It would be wise to replace the intake gasket with a new one than to try to fix the old one. How long it would take to replace the gasket would depend on the model, year and engine type you have.
About 2 hours.
Several manufacturers built 3800. Without that information no answer can be given
Replacing a lower intake manifold gasket on a 3800 V6 engine typically takes about 4 to 6 hours for a skilled mechanic, depending on the specific vehicle and any additional complications that may arise during the process. This job involves removing various components such as the intake manifold, and it can vary based on the mechanic's experience and the tools available. If you're doing it yourself, it may take longer, especially if you're unfamiliar with the engine layout.
a bad head gasket will result with compression and oil/coolant mixxing in the blocka badupper or lower intake gasket will result with coolant in crankcase or exaust manifold which causes white smoke comming out of the tail pipe...if your gonna change the upper or lower intake gaskets change them both at the same time... it saves you money in the long run
if its a v6 and you take your time. it takes about 6-8 hours, depending on how fast you work !
depends on the mechanic, should only take like an hour at most.
you can as long as you use your TBI heads if you want to use the vortec heads with TBI you will need a special intake manifold or a carb manifold with a adapter to mount your throttle body to the carb manifold heres some more info TBI heads will mount to the vortec block TBI intake manifold has 12 bolts vortec intake manifold has 8 bolts
That is a common problem with the vortec 350 engines. The intake manifold gasket starts leaking in the corners of it. That is where the water jackets are and it's only about 1/4 of an inch wide and when it starts leaking it allows engine coolant to leak into the lifter gallery and into the oil. Need to replace intake gasket as long as you no it did not freeze and crack the engine block.
You probably burnt out the thermostat.Or less likely if the overheating was over a long period of time then you can damage the head gasket or intake manifold gasket.
there is a finite amount of information that will fit in this box, buy the service manual for the vehicle it is a long and complicated proceedure to explain here.
Disconnect the throtle cable and see if it shows down. If so replace the cable. If not clean the idle control solonoid. If this doesn't work it might be a gasket leak between the upper and lower intake manifold. Try spraying WD 40 where they are bolted together, if the idle drops replace the gasket. Note, the inside bolt is reached from the top of the upper manifold, T-40 torx head. It is a long torx, Snap-on has one for 28 bucks.