Got my Head on straight!

Kel · Post by **Kel** » 08 May 2008, 02:24

After a marathon of wrench turning, I got my cylinder head back on the other day. With fingers crossed and a prayer to the auto repair gods, it started right up with a single turn of the key. It took a while, with messed up part orders, slow machine shop (they do good work though) and other delays.
I bought this car with a bad head gasket so I knew what I was in for. Turned out the head was warped so bad the cam could hardly turn. I believe what caused the head to overheat was a clogged coolant passage in the head gasket. The gasket itself has a restricted opening to create a bit of backpressure in the head to keep it full of coolant. The 1/4" hole was clogged with crud so I think water could go in but couldnt really get out.
It drives great though, and has turned out to be very nice car for us.
Kelly

crazy_frog · Post by **crazy_frog** » 08 May 2008, 12:27

I always thought a head gasket was an easy fix. You just remove the head and replace the gasket. Thanks for clearing that up. So, it sounds like when you blow a gasket you end of with an overheating problem that warps engine parts. Glad the car is running good now.

Mind sharing with us the cost of something like that?

Kel · Post by **Kel** » 08 May 2008, 16:19

Well, it isnt really rocket science, but "just" removing the head involves removing a lot of crap to get at it. Then putting it all back together properly. If you are patient and organized, I'd say anyone could do it. Almost all of the cost to have a shop do this is in the labor.
I spent about $150 in parts (gasket set, head bolts) and $400 to have the head rebuilt. My head was quite warped and needed it. If your head is OK (have a machine shop pressure test and measure it for flatness; about $50) this would be a relatively inexpensive job.
A leaking head gasket can cause different symptoms depending on where it failed. When my head warped it allowed exhaust gasses to go into the coolant passages and caused the coolant to blow out the reservoir. It ran fine otherwise. The gasket itself didnt apear to have failed, it looked like a coolant oriface in the gasket had become clogged, causing the head to heat up. a good reason to flush your cooling system i suppose.

instarx · Post by **instarx** » 10 May 2008, 04:55

crazy_frog wrote:I always thought a head gasket was an easy fix. You just remove the head and replace the gasket. Thanks for clearing that up. So, it sounds like when you blow a gasket you end of with an overheating problem that warps engine parts.

It is more typical that an overheating engine will warp a head and/or cause the head gasket to blow rather than the other way around. Having said that, a blown head gasket can cause overheating if it blows all the coolant out of the expansion tank. That happens because exhaust gases from the cylinder vent into the coolant system and over-pressure it. It can also cause coolant to blow into the oil pan which is very bad.

As Kel said, heads aren't really "hard" to replace - in theory they just unbolt, but there always seems like there are a zillion bolts, not all easy to get to. You have to remove both the intake and exhaust manifolds as well as the head bolts themselves, plus accessories like A/C pump and alternator may have to come off. Plus you have to re-tighten all those bolts in a particular order to a particular torque. It's a pain.