Cracked head replace?

First post but a long time lurker so here is a little background. I was given (fo free!) a 2000 supercharged 3.4L Tacoma access cab 4x4 with 230,000 miles. Since I received it I have replaced the plugs, had someone replace the cat, replaced the o2 sensors, put in a new starter, and after a lot of heart ache found out that it was running rough because of a 30 dollar MAF sensor. The truck was running great until one day it overheated on me just outside of town. Thermostat got stuck and after a mechanic did some tests I was told I cracked a head. Now for the question. While im looking at prices for the repair does anyone have any recommendations for new heads? Mechanic quoted me $800 to have the old ones sent to a machine shop. But after a quick google im seeing heads priced for close to that. Now im not super mechanically gifted so I will have to pay someone to do the work but should I just get new heads or get them machined? Thanks in advance for any help!

 

Personally, I would get the new head. Once metal has been heated enough to crack, the temper is different in that metal. It’s strength would always be suspect, even if it was successfully pressure tested. Just my opinion.

 

You can't do some tests and find a cracked head. You have to remove and visually inspect it. The symptoms of a cracked head are identical to a bad head gasket.

If you do need a new head and cost is essentially the same, just replace it. It will put you on the road faster.

 

I believe you may have a bad head gasket, but cracked head? And then the mechanic wants to have the heads machined? I would think if the head is cracked he would tell you that the head is no good.
I do agree if you are going through the trouble of taking the heads off to replace gaskets you should have the heads freshened up, but then costs would concern me. Maybe take a look at getting a different used or remanufactured motor. Considering your mileage.

 

I agree, there is NO way to tell if the heads are cracked until they are removed.

I would replace the heads with new if the motor was overheated

 

Do you know the what caused it to overheat? I'd make sure I fix that before running with the new heads.
If you think it was the S/C, I'd be willing to take it off your hands, you know, just to help you out.

 

Supercharger will not cause the motor to overheat, but your correct, you need to find out why
the motor over heated, if it’s a blown or cracked head it will be obvious when the heads are removed

 

Be sure to find the leat first. Now if someone is seeing steam coming from under the intake manifold, there is a metal heater tube that's sealed with RTC that runs under the Lower Intake Manifold (LIM).

If someone is not familiar with the 3.4L they might mistakenly think blown gasket or head when it's only that place where that pipe mates to the block that might be the problem. Just an idea for something to check if there is steam coming up from under the LIM.

 

Lemme guess, the mechanic said you have a cracked head, but he happens to have a line on a new one (for a good price)??

As others said, there's no test for a crack. Fix the overheating issue (sounds like you think it was a stuck t-stat?) and take the head(s) off and inspect the head gasket and the head itself.

 

Thank you all for the replies. CS_AR I did not see any steam coming from under the intake manifold and im getting coolant in my oil. From what im seeing I think I will be going with new heads for the engine. I did already replace the thermostat and that was how I knew it was stuck. took everything I had just to compress it a little bit. The new thermostat had much more give. Sorry Wsidr1 but I think even if I got rid of this truck Id take the SC with me!

Now any suggestions on new heads? a website or link would be much appreciated!

 

Did you ever get new heads? If so, where’d you end up getting them from? I’m looking for new ones for my 99 but all the online places are either pricey or have iffy reviews.

 

You get what you pay for.

https://m.youtube.com/watch?v=iSFpwnCuBDk&t=13s