How do you replace the head gasket in a 1991 Toyota v-6 3.0 engine you know it's difficult but any forwarnings?

Answer 1

The biggest warning would be, if you haven't done it before, either have someone else do it or have an experienced mechanic show you how. First, if it's overhead cam, the above advice is even MORE relevant. Next, you have to remove all of the peripheral stuff, anything that keeps you from getting the heads off. When you pull the sparkplug wires and/or distributor, make sure that you keep track of where the wires went. Also remove intake and exhaust manifolds and anything that is hanging from the heads. Pull the rocker arms and push rods (if applicable) and make sure you keep track of where they came from so that you can put them back in the same place. Pull the heads and make sure that you take them to a machine shop to have the heads resurfaced. Any time a head gasket goes, you can bet that the heads are probably warped. While the heads are there, you may as well have the valves and guides reconditioned. When you start putting it all back together, make sure that you have a calibrated torque werench and know how to use it. Follow the tightening sequence that you get from the machine shop, and don't THINK of doing it without the torque wrench. If you have hydraulic lifters, consider yourself fortunate. Put the pushrods and rocker assemblies back together. If you have MECHANICAL lifters, you get to adjust the valves, then you get to adjust them again after about 300 miles. Put the rest of it back together and hope you haven't messed anything up. OR You can take it to a shop that does this kind of thing. It will cost you a lot, maybe more than the vehicle is worth, but at least it will work when you're done.