How common is a cracked head?

[themike]

So I bought an 89 240 SX with a KA24E under the hood. Supposedly this motor was just swapped in after the last motor let go. I had it towed to my house because it wasn't running(possible fuel pump, turns out the injectors were not plugged in the right order and there was a ground problem).So now that it runs on all 4, there is a lot of smoke coming out of the exhaust. Possible blown head gasket, could be cracked head.My question is: How easily do the KA24E heads crack? I would like to just replace the head gasket and chain, but I am worried that if I pop the head back on there that it will still leak.I have the option to get another motor for it, but would like to go over that motor before I HAVE to throw it in.

Thanks in advance....mike

[deviousKA]

How long have you run it after you got it running properly? Most likely all that smoke and steam is just burning out from the exhaust from when it was running poorly, common. The KA heads do not crack very often, if anything the cylinder head may be warped.

Run it longer and see if the smoke clears up.

[Slo_240sx]

Anything will crack a head if its been overheated. Just make sure you have the head sent out and resurfaced and take a flat block and use some 220 grit sand paper and flatten the deck of the block. Make sure you install the cams and timing chain properly or you are going to be replacing valves.

[nonchalant rage]

is it leaking on the outside? or are you finding oil in your coolant and vise versa?

[themike]

I never actually had a coolant issue. I was concerned with the fact that I was told the car had a blown head gasket.What I couldn't figure out was the car had 170psi compression in the "dead" cylinder and there were no bubbles in the overflow. So I got it running on all 4 cylinders and let it run for a while.(not long enough, but it was low on gas.)As it turns out the car just had A LOT of coolant in the exhaust, probably in the resonator. The guys that put the motor in really overlooked a lot of little things that were important, but oh well. The car runs strong(er) now and just needs new rear tires :There are some maintainance issues that have to be sorted out still now, but it's almost ready to be inspected.

thanks for the replies(sorry it took so long, but the email notinication os off for som reason...)mike

[firehawk240sx]

i have the same problem but i got compression back through the radiator.. Suspecting warped head or cracked head any additional infomation would be appreciated Thanks