Live and Learn..

HackersDna

Test don't Guess
#1
So I’m still an infant in the GN world and I will say that they make you question and double check everything!! My situation...
I buy a used BGC intake and an early set of GN1 Aluminium champion heads. I’m mocking everything up and I sit intake down with gasket and tighten it up with a set of SS bolts that are for a champion intake. I was told that the deminsions are the exact same between a Champion intake and a BGC. The bolts are all the exact same size, “Which came from a big name vendor that I bought in person and not thru the webs”. Anyways I start all bolts by hand and just snug with a battery powered 1/4 drive. There were 3 that got tight. Didn’t think anything about it. Well after the final mock up and all looks good it’s time to disassemble to use sealer and reassemble for final time.
4 bolts don’t want to come out and 2 snap off in the cylinder heads. Nice right.. Well I measure to find out what the hell happened. I knew that I cleaned and chased all threads. Well after measuring the holes of the heads and the size of the bolts I found out that if they bottomed out there could be almost a 1/4” to much bolt and the battery tool just made those nice shiny, sharp bolts eat into the heads. So here I am.. thinking you must check every. Single thread and height on these dam engines yourself. Don’t take final words from anyone just trying to get your dollars.
It’s all my fault this happened I’m just hoping that new guys will take some advice from a guy who admits all his screw ups. Cheers!!
 

Attachments

#2
First find as close to center as you can and punch it with a point punch the drill it with a left handed drill bit.

Hope it will catch and spin out so you will not have to tap in an "easy out " and then try your luck.

Yes, I have made enough mistakes for five people.
 

rag231

Well-Known Member
#3
You could have been using a tapered tap instead of a bottoming tap when you were chasing. The bottoming tap's threads go to the very bottom where as the tapered tap has about 1/4 of no threads at the bottom. Whatever new aluminum threads that you created at the bottom of the whole was chewing into the old threads of your heads. I would measure how much bolt is still in the hole and you can assess you damage from there. If the broken bolt is still near the bottom of your hole take the heads to a machine shop and they can probably drill it out enough times to save the current threads that you have left and no helicoil would be needed. If you backed the bolt out over an inch ( using this as an example) ripping up threads, you may be able to drill it enough times to save the few threads that you have left and work a tap in there since those are intake holes and the bolts may not go down that far. I seriuosly dont think the reverse drill bits will work. A machine shop can chuck it up perfectly straight and drill it straight, it would only take a few minutes. I'm not saying that it cant be done at home but...I dont think that I would be using cheap drill bits to drill it out either.
 

750H.P.V6

Old confused member
#5
It's a good illustration that anyone assembling parts and hardware from different sources needs to take the time to check that the bolt length's are correct for the hole. A similar story from many years ago; A friend was assembling a Stage 2 motor for the first time and didn't check the head bolt lengths. As he put torque on one of the intake side bolts (which was bottomed out in the hole) he broke the casting ear off ruining the block. I've seen a number of instances like this over the years, even with ARP hardware I've found bolts that are the wrong length. I hope your situation isn't too hard to fix.

Neal
 

HackersDna

Test don't Guess
#6
You are exactly right 750.. Actually all you guys are right. Michael I was using an actual thread chaser and not a tap. It's basically the same thing as the bottom taps but not as sharp. I've seen sharp taps destroy good threads. This was a case where I just let my guard down thinking I had the cat licked. I will use a machine mill to drill these out. I'm sure they can still be used but I've been in a fight with these heads since day 1. I think my higher power is telling me to move on, lol. I have Bison looking for some new castings from this decade and I'll put these in time out or pass them along to help some young gun trying to get their start.
Really what makes me angry is if this would of happened a week earlier I could of picked up a new set at the NATS.

Thank you guys for just listing to me complain. I'm sure you guys understand that the wife does not want to hear this crap! I needed for someone out in the world to hear how dumb I felt as well as the price I have to pay now. I will pass that along to a young gun as well.
 

gdsims231

Active Member
#8
I would try welding a nut on them first and see if it will back out. It’s rare we have to drill one out of aluminum heads.
 

turbo nasty

Goat Milk Racing
#13
Take them to a machine shop and get the bolts removed. Also, FYI the early Champ GN1 castings were proned to cracks between the intake valve and spark plug in the CC as well as cracks on the outside by exh ports and had fasterner holes. Check them over throughly
 

HackersDna

Test don't Guess
#17
Wow... Was feeling the comradely until Earl shows up. I said I did it, so I did it. It was a 1/4 battery POS that was used after all bolts were started by fingers not a 3/4” impact, and remember this was mock up with no sealants. The device I used was not the problem it was the fact that.. I did not measure depth vs length. And I wanted others to learn from my dumbass screw up.
I wasn’t asking anyone for help or to fix my problem. I was trying to help the next guy new to these engines. And maybe hear some other cool boneheaded stories. I thought that is what we were supposed to be doing on this forum. Helping one another and admiring this PITA engine.

So point to this, for all the guys who are not perfect. Regardless of what any vendor tells you or SELLS you, regardless of how meaningless you think the thing you are doing is at the time. Don’t assume anything at anytime. Check everything, question everything. Or it will bite you.
 

NY Twin Turbo

All the good stuff.....Times 2.
#19
Wow... Was feeling the comradely until Earl shows up. I said I did it, so I did it. It was a 1/4 battery POS that was used after all bolts were started by fingers not a 3/4” impact, and remember this was mock up with no sealants. The device I used was not the problem it was the fact that.. I did not measure depth vs length. And I wanted others to learn from my dumbass screw up.
I wasn’t asking anyone for help or to fix my problem. I was trying to help the next guy new to these engines. And maybe hear some other cool boneheaded stories. I thought that is what we were supposed to be doing on this forum. Helping one another and admiring this PITA engine.

So point to this, for all the guys who are not perfect. Regardless of what any vendor tells you or SELLS you, regardless of how meaningless you think the thing you are doing is at the time. Don’t assume anything at anytime. Check everything, question everything. Or it will bite you.
Don't worry much about anyone judging you on this one.

Try dropping some stainless hardware into your intake. This was a bad day.

Or an even worse day, down your passengers side header and not even knowing you did it until you hear the turbine wheel sling apart and then listen to the blades make a cool tinging sound down the exhaust system and blow out the tail pipe.

I'll give you time to catch up.
 

TexasT

Texas, Where are you from
#20
Any one who doesn't have stories like the about either doesn't wrench or is a liar. Everyone who has wrenched has silly things that have happened and it is just part of learning. I know early in my wrenching I was helping a guy and asked why he didn't use the impact or any air tools and he told me that it might be quicker on some jobs but the one that go wrong, go real wrong with that kind of "help". He liked wrenches and ratchets so he could "feel" the fasteners. I try to live by that knowledge.