ls1 head bolt thread taps
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TECH Apprentice
Joined: Dec 2010
Posts: 325
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From: canada
ls1 head bolt thread taps just about to put the head on my 01 trans am ws6. i have hear on hear that a couple of people have taps for the tread bolt holes. to clean them. whare did you guy get them?
All you really need to do is take one of your long old head bolts, get a grinder with a cut-off wheel, and cut some slots in the bolt, 3-4 will do in equal spaces on the bolt, that will allow the bolt to thread in the hole, and chase the threads, while the debris will have the slots to go in. I have done this a couple times, works like a champ. Hope this helps.
And if You want to go 1 further heat the end of bolt and hit with a hammer fust enough to mushroom it a little bit ,,,,,,,,,,,,,although not very easy to not enlargen it too much . If the bolt is tight then try another . Good luck
All you really need to do is take one of your long old head bolts, get a grinder with a cut-off wheel, and cut some slots in the bolt, 3-4 will do in equal spaces on the bolt, that will allow the bolt to thread in the hole, and chase the threads, while the debris will have the slots to go in. I have done this a couple times, works like a champ. Hope this helps.
Yes good point ,,,,,,,sorry ,,,,,,,,I would'nt recommend the extra part about mushrooming the bolt for an aluminum block but I would recommend for the aluminum blocks the method of grooving the bolt longways as long as the grinding part does'nt melt the steel too much . But for the iron blocks I would say both the previously described methods the grooving and/or the grooving and mushrooming making sure to follow the previously described things to watch out for .
Yes nice common metric size ,,,,,,,,,,,,,,11mm/2.0 pitch
Yes nice common metric size ,,,,,,,,,,,,,,11mm/2.0 pitch
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Banned
Joined: Oct 2009
Posts: 992
Likes: 1
Geez uzzz its not a tap its THREAD RESIZER! Anyone who just cuts flutes on a old bolt and uses that is COMPLETE idiot.......its worse than doing nothing at all. Cutting those flutes using a grinder etc is going to leave rough edges on the bolt threads, run that down the holes and good luck. The thread resizer does just as the name implies.....it cleans and adjusts the threads back to spec.
Geez uzzz its not a tap its THREAD RESIZER! Anyone who just cuts flutes on a old bolt and uses that is COMPLETE idiot.......its worse than doing nothing at all. Cutting those flutes using a grinder etc is going to leave rough edges on the bolt threads, run that down the holes and good luck. The thread resizer does just as the name implies.....it cleans and adjusts the threads back to spec.
UHHH,, there must be a ton of complete idiots on this site alone,,GENIUS.. I am an idustrial maintenance mechanic, and assure you I have drilled and tapped, and repaired, more bolt holes than YOU ever thought about. There will be no ROUGH EDGES, that is ignorant, You are removing metal from the bolt and giving any debris a place to gather to get it out of the hole, and you think the minute one of those leading edges makes contact with the aluminum its gonna damage the threads in the block, I hope you are kidding. (the sharp part of a tap that actually does the cutting is the leading edge) I also use Thread chasers,, as well as rough taps, taper taps, and bottoming taps, but have never heard of a thread resizer. Dont even know what that is,,(Neither does google I searched thought it may be called that somewhere else in the country) The holes are not damaged, You are just running the bolt down to remove any possible debris left from the old head bolts, all that is needed is to clean the threads out. Not re-tap them. The bolt with a groove (its called a flute on a tap and drill bit) works just fine, run it in a couple times, then spray some brake cleaner in the hole, and compressed air to blow it out. Or you can buy that special LONG tap and use it once,, If you built engines for other people then I could see that, but there are a TON of us IDIOTS who have used the bolt method.
Banned
Joined: Oct 2009
Posts: 992
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uhhh,, there must be a ton of complete idiots on this site alone,,genius.. I am an idustrial maintenance mechanic, and assure you i have drilled and tapped, and repaired, more bolt holes than you ever thought about. There will be no rough edges, that is ignorant, you are removing metal from the bolt and giving any debris a place to gather to get it out of the hole, and you think the minute one of those leading edges makes contact with the aluminum its gonna damage the threads in the block, i hope you are kidding. (the sharp part of a tap that actually does the cutting is the leading edge) i also use thread chasers,, as well as rough taps, taper taps, and bottoming taps, but have never heard of a thread resizer. Dont even know what that is,,(neither does google i searched thought it may be called that somewhere else in the country) the holes are not damaged, you are just running the bolt down to remove any possible debris left from the old head bolts, all that is needed is to clean the threads out. Not re-tap them. The bolt with a groove (its called a flute on a tap and drill bit) works just fine, run it in a couple times, then spray some brake cleaner in the hole, and compressed air to blow it out. Or you can buy that special long tap and use it once,, if you built engines for other people then i could see that, but there are a ton of us idiots who have used the bolt method.
You woooood need a 20 ft ladder just to get up to azzhole level.
Yeah - Don't ever do this. Ever. All you'll do is distort the bolt in an unpredictable way which will in turn distort the threads in whatever you're trying to clean out.
Teching In
Joined: Nov 2011
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Tell me guys what if a moron (me) doing his first head install on one of these didnt clean the holes and now I have a hairline crack on the outside of the block, M I doomed or is it ok. Does coolant flow through these head bolt holes that could cause me a problem? TIA for the help
A cracked block could lead to anything
If you're very very lucky, its a superficial crack from the blind hole to the exterior of the block
If you're like 98% of people who screw this up you hit a water jacket or oil passage and the block is officially scrap
LS1 head bolts are long to compress the cyls from the base of the sleeve, so superficial cracks are extremely rare because of the immense hydraulic pressure required to split the thicker lower block material
Chalk it up as an expensive lesson and get a replacement block. Like anything, the time is in the prep work. You wouldnt spray a car before sanding and filling it would you?
If you're very very lucky, its a superficial crack from the blind hole to the exterior of the block
If you're like 98% of people who screw this up you hit a water jacket or oil passage and the block is officially scrap
LS1 head bolts are long to compress the cyls from the base of the sleeve, so superficial cracks are extremely rare because of the immense hydraulic pressure required to split the thicker lower block material
Chalk it up as an expensive lesson and get a replacement block. Like anything, the time is in the prep work. You wouldnt spray a car before sanding and filling it would you?