Stuck Head Bolts!! @#$%@#$%*

[rewiredz]

i dont know if this will work any better then a impact wrench, but this is what i use to get flywheels off sometimes. Impact driver

fairly cheap and pretty effective.

[Galaxybj]

Arne, you hit the head (no pun intended) of the nail on the bolts. The ones that have come out, the threads are fill of guck. The reason I am pulling the head is that I had a seep where the head and block meet above #4 and 5 sparkplugs and the last three cylinders are damp. I had 4 that I had pull like a nail out of the head and one that I can't pull through. The stubborn one - I tried the heating trick - no luck. I resorted to the cut it off technique rather than going ahead with breaking it. Hacksawed halfway through then twisted it off. Now I have to get the head loose from the block to get it off to the machine shop. Thank you all for the input.

Oh, by the way, I ordered the turbo head bolts and have made notes from other threads on how to make them easier to remove in the future.

[JimmyZ]

I had one do the same thing but it eventually broke after applying excessive torque. I was able to weld a head on the 1/4" protruding stump and then it turned out easily. It seems that the heat helped loosen things up. I tried playing a torch on the block where the bolt resides but no joy. (side of block) The heat from welding a head on the bolt close to the deck did the trick.

Arne has a great idea/point. Sacrifice the head bolt and work at it after you get the head off. This will leave you with a 3" shank to play with instead of a stub. Once the head is off you can apply some parts blaster/pen lubricant and work from there. These bolts are next to impossible to drill! Don't think that you can get it with an easy-out. Get a stud remover and soak the thing with pen/lube for a day or two. This would be the last resort next to welding a head on. If all else fails then a shop can EDM it.

You will have no luck trying to undo the bolt from the topside. The cap of the bolt allows no pen/lube to get through.

2c

Jim

[Arne]

Now I have to get the head loose from the block to get it off to the machine shop.

Again, from experience I'd now say that the ring of crud on the broken bolt is quite firmly wedged in the head. At this point I'd try lifting the engine slightly with an engine hoist (cherry picker or anything similar) connected to brackets bolted to the head, not the block. If the bolt is stuck hard enough that the wedged bolt will support the entire engine's weight, you can do some judicious hammer action on the block to try to break it free. That way you aren't hammering on the soft aluminum head. Don't lift the engine much, just the minimum amount to get all the weight off the ground. Even 1/8" should do.

[Galaxybj]

Ok Arne and others, I have tried the floor jack with a 2x4 under the edge of the head on the drivers side and jacking the jack and pulling from the top side with a chain connected to the lift points and some hammer action on the block. This head does not want to come off. I do not want to resort to removing the engine from the car. Any other ideas?

[texasz]

I'm glad I searched for this topic and came across this thread again. I'm tearing down another engine this one with two stuck bolts on th intake/exhaust side of the head. This thread have provided me some additional ideas to go attempt...and also explains why my shots of PB Blaster have not helped any (I suspected as much though didn't want to leave any stone unturned).

I also used a plumber's torch on the block where the bolts screw in as well as on the bolt heads with no luck. Maybe I should pull out my oxy acetylene torch for this...I'm just afraid of warping/melting something (the head is only aluminum after all).

[Galaxybj]

It appears I failed to post what I ended up doing to get the head loose from the block and the remains of the one bolt. I talked to the manager at Rio Rancho Import Auto Repair and he suggested stuffing small diameter rope into cylinders 1 and 6 then turn the crank by hand to use the force of the pistons to push the head off. It took a bit, but it did work. I then used a left handed drill bit to remove the rest of the bolt.

[texasz]

Well that's over...kinda. I ended up cutting the heads off the two bolts yesterday and working the head off...that was not easy and involved more cutting. The head seemed to slide pretty easily on one head bolt and not the other. After TONS of pounding with a 3lb hammer and a couple 2x4s (we destroyed the first one) and pulling up on the head at the same time we only managed to move the head up about 1" and decided a different course of action was in order.

Time to cut the stuborn head bolt between the head and block, though it was not accessible with my cutoff wheel so I had to use a sawsall...this made me very nervous as I didn't want to damage anything. Those head bolts are VERY tough, I burned through 2 and 1/2 metal blades cutting this one bolt. WOWZERS!!! So now the head is off after a little more persuasion.

Next is getting the rest of that one stuborn head bolt out of the hole in the head. I figure putting the head on wood blocks and using another head bolt and the 3lb hammer I should be able to pound it out easily right? NO! I only managed to move it about another 1" before stopping for the night. I filled the hole the bolt was in with PB Blaster and called it a night.

Wise move! This morning I wicked out the hole of the PB Blaster with a papertowel and took the same approach with a head bolt and the 3lb hammer. about 6-10 blows later and it's out!!

After inspecting the bolt I just removed it was obvious why it was so stuck. Here's a link to pix: http://www.pape.ws/gallery/v/Our_Life_Together/Our+Hobbies/Allan_s+Hobbies/240Z+Car/My+First+240Z/Totally+Rusted+Head+Bolts/?g2_fromNavId=x821ef459 Check out all that deposit on shown in the second pic.

I'm leaving the two bolt remains in the block for the machine shop to deal with.