Hey guys, so I've got a bit of a concern. I have been doing some work on my 02 Z06 (replacing the known bad valve springs) and it's been quite a nightmare of a job...not to go into too much detail, but I thought I had to pull the head on the drivers side. I accidentally dropped something in there while trying to find TDC on cylinder 3, and began the process of taking the head off. Half-way thru, we came up with the idea to take a telescoping magnet pen, cut off the magnet head, and solder it to a thick wire. This actually allowed us to get the small tool we were using to gauge weather or not the cylinder was at TDC.

At the point we got this, we were relieved to not have to finish pulling the head off, and then started to throw everything back together. I purchased new OEM GM head bolts, and torqued them down to spec using an angle meter and all seems good. The car is now back together, with the exception of the plugs and coils back on..and I ran compression on each cylinder, which checked out at between 185-190psi.

Here's what I didn't realize I needed to do tho. After reading a bunch of DIY head removals, I realized that we did not clean out the head bolt holes in the block. Since we didn't remove the head, and never even separated it from the block, it didn't even occur to us that this was something that had to be done. It sounds like some coolant can "splash" into the holes when you actually pull the head off and break the gasket seal. My concern is, even tho I didn't pull the head, I took all the bolts out (except for the furthest small bolts up by the intake manifold), and it allowed for a VERY small amount of coolant to leak out, leaving a very small puddle on the garage floor. It was nothing like the amount that falls out when you actually pull the head. Very tiny puddle, enough to be soaked up by one piece of paper towel. So i'm not sure what the odds are of some coolant even making it into the head bolt holes, especially with the gasket still being in place and all.

So here's my question..do I need to disassemble everything and pull the head to make sure those bolt holes are clean? The new bolts are already torqued down and the head gasket is sealed with no leaks..so I'm not sure if this is a concern. If i pulled the head, this is a no-brainer, but I don't want to go through all that work if people who know more than me, don't think it's necessary.

I heard that if there's any liquid in the holes, the heat from the engine can cause the bolts to expand and lead to cracks in the block. I just really don't think anything got in there...but I'm not a pro and am just taking a guess.

Let me know what you experienced guys think about this.

Thanks!!

 

My advice: pull the head....better safe than sorry. Coolant on the floor means that the head gasket DID leak when the bolts were removed. Heck I would not even trust the integrity of the head gasket at this point. Block damage occurs when a head bolt is tightened into a hole that contains liquid. Since liquid does not compress, something has to give. What happens is that the bottom of the hole is broken out. This can only be checked after the head is removed.I would also encourage you not to use the mickey mouse TTY oem bolts. Bite the bullet and purchase a set of ARP bolts which are MUCH easier to properly install AND can be reused.

 

It don't matter at this point....the damage is done as you tighten the bolts and the coolant trapped inside compresses and cracks the block. I say look at it carefully for cracks if you find none you're ok. Did you hear any strange popping sounds as you were tightening the bolts?

 

Popping isnt always accurate. I have done quite a few of the heads and popping is pretty common place when tightening down the bolts. did the bolts feel spongy going in and do you see coolant anywhere? mine popped assmebling my ls6 just as they did with my old ls1 and both are still living healthy happy lives

 

Nope I didn't hear any popping whatsoever, no sponginess while tightening them down and no coolant coming out while torquing either. Everything seemed pretty normal and easy, other than the last 90 degree turns on the bolts requiring some muscle..which is pretty normal.

 

So i just jacked the car back up and spent about an hour looking at the block with as many angles as I could - zero cracks that I can see anywhere. Of course, this only counts for the lower 5 bolts. The block looks just fine from what the eye could see.

Also - a helpful trick to see in those difficult angles. Use your cellphone, go into video-mode, and turn the flash on. This'll let you use it almost as a "scope". Sure helped me a lot tonight!

 

If it was quiet while tightening nothing happened. When the block cracks you know something bad just happened.

 

Thanks guys. Just to give an update, I put everything back together and started it up. The car runs like nothing ever happened, no leaks anywhere and no white smoke coming out the pipes. So it looks like I dodged a major bullet!