Stupid cylinder head mistake
Thread Starter
Joined: Jul 2014
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From: My own internal universe
Stupid cylinder head mistake I had the pcv issue bite me really bad in a 1999 TA stock internals engine. So, I bought the ls6 pcv valley cover and ls6 intake while I was at it. The stock ls1 intake was plugged with oil sludge to the point it would hardly run. I could not even snake two of the runners out it was so bad.
When I took the intake off there was sludge in the intake ports so I pulled the heads. Had them cleaned and then P/P. Lapped in all valves. Reassembled heads. Installed 0.041" mls gaskets. Sprayed them with copper coat.
Now the mistake. I forgot to blow out the thread holes in the block for the cylinder head bolts. While installing, I started seeing water come out of the bolt holes, but didn't notice until the final two lower bolts on the second head. So, I have torqued all my brand new bolts to yield per the specs, except that I also did not oil the washer on the thread, so I likely did not torque properly anyway. It was late and 117 outside, so I wasn't thinking. Given the water and lack of oil, I'm not really sure that the bolts actually yielded. I think I'm just fighting the water in the holes.
Sorry for the long post, but wanted all info presented. Now - since this motor has not yet run on these bolts, can I simply remove them, clean the holes, and reuse them? If so, can I remove them one at a time, install the new one properly, and then go to the next bolt, or do I need to loosen them all in sequence? If I had run the engine I wouldn't be asking. I just really don't want to scrap out a set of brand new bolts.
Thanks guys
When I took the intake off there was sludge in the intake ports so I pulled the heads. Had them cleaned and then P/P. Lapped in all valves. Reassembled heads. Installed 0.041" mls gaskets. Sprayed them with copper coat.
Now the mistake. I forgot to blow out the thread holes in the block for the cylinder head bolts. While installing, I started seeing water come out of the bolt holes, but didn't notice until the final two lower bolts on the second head. So, I have torqued all my brand new bolts to yield per the specs, except that I also did not oil the washer on the thread, so I likely did not torque properly anyway. It was late and 117 outside, so I wasn't thinking. Given the water and lack of oil, I'm not really sure that the bolts actually yielded. I think I'm just fighting the water in the holes.
Sorry for the long post, but wanted all info presented. Now - since this motor has not yet run on these bolts, can I simply remove them, clean the holes, and reuse them? If so, can I remove them one at a time, install the new one properly, and then go to the next bolt, or do I need to loosen them all in sequence? If I had run the engine I wouldn't be asking. I just really don't want to scrap out a set of brand new bolts.
Thanks guys
Thread Starter
Joined: Jul 2014
Posts: 10,450
Likes: 1,873
From: My own internal universe
Havoc and reda4 - that's what I was afraid of. Also why I asked before just reusing them. I almost did buy the studs. Now I'm ticked at myself even more.
J - is that really possible? I'm sure if I ran the motor it would happen, but just from wrench torque? Side question. How much did you feel like you gained porting your heads? Was it worth the time?
J - is that really possible? I'm sure if I ran the motor it would happen, but just from wrench torque? Side question. How much did you feel like you gained porting your heads? Was it worth the time?
Thread Starter
Joined: Jul 2014
Posts: 10,450
Likes: 1,873
From: My own internal universe
Havoc and reda4 - that's what I was afraid of. Also why I asked before just reusing them. I almost did buy the studs. Now I'm ticked at myself even more.
J - is that really possible? I'm sure if I ran the motor it would happen, but just from wrench torque? Side question. How much did you feel like you gained porting your heads? Was it worth the time?
J - is that really possible? I'm sure if I ran the motor it would happen, but just from wrench torque? Side question. How much did you feel like you gained porting your heads? Was it worth the time?
TECH Fanatic
Joined: Jun 2011
Posts: 1,343
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From: Katy, TX
I agree with you that the lack of oil on the threads would mean that there is less pre-load in the fastener given the same torque applied. Have they been yielded? maybe, maybe not.
I would recommend buying a set of ARP head bolts. They can be had for $170 or less if you shop around.
Short of that, here is the nerd way to go about it:
1. Remove all bolts and clean holes thoroughly. I use a drinking straw duct-taped to a shop vac nozzle to vacuum out the very bottom of all the holes.
2. Buy 1 or 2 new head bolts from the dealer. Oil the threads and torque down per factory specs. It would be ideal if you have a digital torque wrench and can record the amount of torque applied. Short of that, a beam-type torque wrench coupled with an angle gauge should work OK.
3. Re-install 1 or 2 of the "old" bolts with oil on the threads per the factory specs. Measure the torque as per #2. Compare the torque results to #2 above.
4. If the torque applied is the same (roughly), than you have not yielded your "old" bolts, and I would re-use them.
5. If the torque applied to the "old" bolts is significantly less than that for the new bolts, then the "old" bolts are trash.
Worth a shot anyway, good luck
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If you haven't cracked the block ( https://ls1tech.com/forums/generatio...bolt-hole.html ) I would pull the bolts and install the heads with an ARP head stud kit. While you should still clear out the bolt holes, using studs eliminates the possibility of cracking the block due to hydraulic compression from bolts.
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Joined: Jul 2014
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From: My own internal universe
That torque measuring trick is a great idea!
I normally use the straw and shop vac method followed by canned air from office max to clean the holes. I just had a bad brain fart.
I'm going to just replace the bolts. It's cheap compared to the consequences. Call it a lesson learned. I was really hoping that the bolts didn't yield until they started seeing compressive forces, but three people on ls1 tech saying better safe than sorry is enough for me.
This time I'll just get the studs and not worry ever again. Very much appreciate everyone chiming in.
I normally use the straw and shop vac method followed by canned air from office max to clean the holes. I just had a bad brain fart.
I'm going to just replace the bolts. It's cheap compared to the consequences. Call it a lesson learned. I was really hoping that the bolts didn't yield until they started seeing compressive forces, but three people on ls1 tech saying better safe than sorry is enough for me.
This time I'll just get the studs and not worry ever again. Very much appreciate everyone chiming in.
Thread Starter
Joined: Jul 2014
Posts: 10,450
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From: My own internal universe
How would I know if I 
my block? Will I see daylight at the bottom of the bolt hole? Do I need to try a small straw feeling around to see if it pushes through?
my block? Will I see daylight at the bottom of the bolt hole? Do I need to try a small straw feeling around to see if it pushes through? 
Joined: Aug 2007
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From: Turnin' Wrenches Infractions: 005
I tightened one with water still in the hole. Loud crack, bolt started spinning free. Ripped the threads out of the block. Had to buy a TimeSert kit and drill the hole out and place an insert in that hole. Supposed to be strong as stock but I bought studs next go round for piece of mind. Its a mistake I won't make again.
Thread Starter
Joined: Jul 2014
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From: My own internal universe
Paul, I totally missed your post. I don't have anything like those pics showing up. I also did not get any loud cracking noises. I might have gotten very lucky. I'm sure it would have gone worse if I had said :up yours: and finished assembly and fired it up. For a quick and dirty test I got a new bolt to test my "bolts may not have yielded" theory. They did. The bolt out of the box is 1/16" shorter.
Hello arp, and hello delayed assembly
Hello arp, and hello delayed assembly
TECH Fanatic
Joined: Jun 2011
Posts: 1,343
Likes: 8
From: Katy, TX
Paul, I totally missed your post. I don't have anything like those pics showing up. I also did not get any loud cracking noises. I might have gotten very lucky. I'm sure it would have gone worse if I had said :up yours: and finished assembly and fired it up. For a quick and dirty test I got a new bolt to test my "bolts may not have yielded" theory. They did. The bolt out of the box is 1/16" shorter.
Hello arp, and hello delayed assembly
Hello arp, and hello delayed assembly
Thread Starter
Joined: Jul 2014
Posts: 10,450
Likes: 1,873
From: My own internal universe
Very glad I listened to y'all. After cleaning the holes out the old bolts would start but required a ton of effort to turn. The studs went right in like they should.
Also, if it helps anyone, it looks like the bolts stretch at the threads that are not engaged in the block. You can see the threads match up with the stud threads at first. Then there is one thread that is really wide, then the rest of them as you go up the shank are still wider than the bottom ones but closer than that one really bad thread. If you try to reuse, that one really wide thread would totally strip it out
Bottom line is all of you were correct. You can't reuse the bolts. Thanks again to everyone.
Also, if it helps anyone, it looks like the bolts stretch at the threads that are not engaged in the block. You can see the threads match up with the stud threads at first. Then there is one thread that is really wide, then the rest of them as you go up the shank are still wider than the bottom ones but closer than that one really bad thread. If you try to reuse, that one really wide thread would totally strip it out
Bottom line is all of you were correct. You can't reuse the bolts. Thanks again to everyone.
I think the best reason to use studs vs bolts is you aren't grinding threads into aluminum when you tighten the steel nut against the steel stud and get a better torque too