broken Header-Downpipe flange bolts
Thread Starter
Drifting
Joined: Aug 2013
Posts: 1,463
Likes: 0
From: Everett Washington
broken Header-Downpipe flange bolts
was going to put a new exhaust in and STAINLESS bolts, and these junky stock steel ones rusted out beyond belief all 3 on the drivers side snapped in half so im terrified of going on to the other side. i really down want to play contortionist on trying to get the header off and lord knows id throw a fit if i broke those bolts off 
. any quick tips?
. any quick tips?
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
If studs/boltsare rusted where the diameter is noticably smaller than the threaded part .... as much as it is no fun at all ....you need to replace them. PB blaster does pretty good with rust. There's some aircraft stuff that's alot better, K something I think, you need a aircraft maint. connection to get it. A torch and a crayon - heat bolt until red hot then melt a candle or crayon on to it. Wax will be drawn between nut/manifold and bolt/stud. That might keep bolt/stud from breaking coming apart, won't keep them from breaking them putting it back together.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
Are they a stud in the collector (??) or just a bolt with nut? If they are studs, you can drill them out and then just use SS bolts with nuts and lock washers like your thinking.
You can mix 50% acetone and 50% tranny fluid as a penetrating fluid...it is better than anything you can buy.
You can mix 50% acetone and 50% tranny fluid as a penetrating fluid...it is better than anything you can buy.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
On 12-13-2012 Cuisinartvette posted this:
Quote:
Machinist's Workshop magazine recently published some information on various penetrating oils that I found very interesting.
Some of you might appreciate this. The magazine reports they tested penetrates for break out torque on rusted nuts.
They arranged a subjective test of all the popular penetrates with the control being the torque required to remove the nut from a
"scientifically rusted" environment.
*Penetrating oils ........... Average torque load to loosen*
No Oil used ................... 516 pounds
WD-40 ..................... ... 238 pounds
PB Blaster .................... 214 pounds
Liquid Wrench ...............127 pounds
Kano Kroil .................... 106 pounds
ATF*-Acetone mix............53 pounds
The ATF-Acetone mix is a "home brew" mix of 50 - 50 automatic transmission fluid and acetone.
Note this "home brew" released bolts better than any commercial product in this one particular test.
Our local machinist group mixed up a batch and we all now use it with equally good results.
Note also that "Liquid Wrench" is almost as good as "Kroil"
for about 20% of the price.
Steve from Godwin-Singer says that ATF-Acetone mix is best, but you can also use ATF and lacquer thinner in a 50-50 mix.
*ATF=Automatic Transmission Fluid
Quote:
Machinist's Workshop magazine recently published some information on various penetrating oils that I found very interesting.
Some of you might appreciate this. The magazine reports they tested penetrates for break out torque on rusted nuts.
They arranged a subjective test of all the popular penetrates with the control being the torque required to remove the nut from a
"scientifically rusted" environment.
*Penetrating oils ........... Average torque load to loosen*
No Oil used ................... 516 pounds
WD-40 ..................... ... 238 pounds
PB Blaster .................... 214 pounds
Liquid Wrench ...............127 pounds
Kano Kroil .................... 106 pounds
ATF*-Acetone mix............53 pounds
The ATF-Acetone mix is a "home brew" mix of 50 - 50 automatic transmission fluid and acetone.
Note this "home brew" released bolts better than any commercial product in this one particular test.
Our local machinist group mixed up a batch and we all now use it with equally good results.
Note also that "Liquid Wrench" is almost as good as "Kroil"
for about 20% of the price.
Steve from Godwin-Singer says that ATF-Acetone mix is best, but you can also use ATF and lacquer thinner in a 50-50 mix.
*ATF=Automatic Transmission Fluid
Safety Car
Joined: Apr 2011
Posts: 3,660
Likes: 22
There is no short cut to this issue,....recently been there done that.
You HAVE to get the flange red-hot and knock the old studs out. They may be splined bolts similar to axle studs. Or common bolts...either way, they are near welded in place with rust.
Knock the old ones out, drive new grade 8 stainless In and forget it.
TIP
a muffler shop will do this for a few bucks and do it RIGHT....I had my rt side done for $20
You HAVE to get the flange red-hot and knock the old studs out. They may be splined bolts similar to axle studs. Or common bolts...either way, they are near welded in place with rust.
Knock the old ones out, drive new grade 8 stainless In and forget it.
TIP
a muffler shop will do this for a few bucks and do it RIGHT....I had my rt side done for $20
Thread Starter
Drifting
Joined: Aug 2013
Posts: 1,463
Likes: 0
From: Everett Washington
i have a 90% feeling my manifolds are worse 
i might have to just nut and bolt it. @john we use something called yield made by chemsearch its similiar to kroil, ill try that mix though! ill try and get stuff lose. thank you guys, nice too have support for my mistakes 
i might have to just nut and bolt it. @john we use something called yield made by chemsearch its similiar to kroil, ill try that mix though! ill try and get stuff lose. thank you guys, nice too have support for my mistakes
Burning Brakes
Joined: Jun 2005
Posts: 1,191
Likes: 15
From: Wallingford Vermont
There is no short cut to this issue,....recently been there done that.
You HAVE to get the flange red-hot and knock the old studs out. They may be splined bolts similar to axle studs. Or common bolts...either way, they are near welded in place with rust.
Knock the old ones out, drive new grade 8 stainless In and forget it.
TIP
a muffler shop will do this for a few bucks and do it RIGHT....I had my rt side done for $20
You HAVE to get the flange red-hot and knock the old studs out. They may be splined bolts similar to axle studs. Or common bolts...either way, they are near welded in place with rust.
Knock the old ones out, drive new grade 8 stainless In and forget it.
TIP
a muffler shop will do this for a few bucks and do it RIGHT....I had my rt side done for $20
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Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
Studs are M10 X 1.5 X 57 and you'll have no trouble finding new, either OE or the local auto parts store. I can see no reason for doing anything other than studs. I don't believe there's any need for stainless either. If you buy studs and nuts meant for exhaust you'll get the properties required for them.
Kroil does well but for this task the ATF/acetone mix
Kroil does well but for this task the ATF/acetone mix
love the stuff