Grrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr

[The Dude Abides]

Any type of cutting oil or lube needed. Or is the aluminum pretty workable as is.

[GeneralDisorder]

Any type of cutting oil or lube needed. Or is the aluminum pretty workable as is.

 

You can dip the tap in some motor oil if you wish. Aluminium is so soft that you could easily tap it by hand without any lube. I would use lube though just to keep the tap from getting dull. Work it back and forth - when you feel it start to bind turn it back a couple turns to free the chips from the cutting teeth then start cutting again. I typically run the tap in and out 2 to 4 times, cleaning it each time with WD-40 to insure there are no chips left in the threads. Do likewise with the bottoming tap.

 

You can buy a legitimate can of cutting oil - I like the foaming drill bit lube as it stick to stuff better - good for upside down cutting like this. But an ordinary squirt can or rattle can lid filled with motor oil for dipping the tap in will do just fine for this simple job.

 

GD

[The Dude Abides]

So updateing an old thread. Things happened and i never got around to fixing this. How its become so lose i have lost most power in the powerband and exhaust pours into the car at stoplights. Im going to get on this asap.

[GeneralDisorder]

So simple - you'll wonder why you never did it before breakfast on Christmas morning.

 

Really - it couldn't be an easier thing to fix. Biggest concern is getting the tap started straight - but in aluminium that's not a difficult task. Just push and turn - you'll get it.

 

GD

[The Dude Abides]

Thanks again for your help GD, i keep looking at this thread and trying to figure out where go. Piece of cake, ill get it. Oh 1 more thing, i havent looked but since its been snowy and wet and the gasket has been exposed. Is it a good bet that its bad and i should replace it.

Edited January 7, 2010 by The Dude Abides

[The Dude Abides]

Oh and after relooking at the exhaust studs you could buy i can see why you would suggest the all thread. You just have more contace with the metal and not the space inbetween.

[Frank B]

Another tip on cutting anything with threads is to put a nut on it, cut, then turn the nut off over the end you cut. The nut will straighten out the threads you messed up while cutting. Also makes it easier to see what you need to file to clean it up.

[GeneralDisorder]

I would pickup a couple gaskets from the dealer - but that doesn't preclude you reusing the old one's if they are still good. Moisture will damage them eventually as they will rust but if they are not rusted or damaged you can probably reuse them.

 

All-thread is easy to source in the size you need. And it's soft and easily worked with - a hacksaw and a bench grinder or file is all you need to make studs. We never stocked studs at the machinery company I worked for - we stocked all kinds of all-thread (even some left-handed, metric, tool-steel stuff ). You can get any type you can imagine - you can get stainless if you desire and stainless nuts/washers as well.

 

Assuming you have a hacksaw and a file to chamfer the edges with, it shouldn't cost much more than $25 for the whole job including gaskets. (not couting the tap's of course).

 

GD

Edited January 7, 2010 by GeneralDisorder

[The Dude Abides]

Last Q, should i do all 4 since its easy and make it stronger. Or just do this one and get buy until the others go.

[The Dude Abides]

Just checked with local fastenall. They only have grade 2 allthread. Now they say they can special order grade b7 in but it will take a few days. Fine or course thread in 3ft sections.

[phantomcrooner]

Man, last winter i drove from Los Angeles to Bend, OR to see my mom. About 14 hours into my drive with only 30 min to go I lost both bolts in the driver side. I messed around with it for about 20 min. trying to get it "patched up" just to get to her house, I put a longer bolt with a bunch of washers in it, drove about a mile and lost it too. I spent the next 30 miles doing about 35 mph.

 

I went and bought a bunch of bolts the next day, everything seemed tight, no leaks, good to go. Yeah right.

 

I drove it a week that way, started home, about 100 miles into the trip i lost both bolts. Since it was freaking freezing and about to get dark I striped 3 pieces of braded speaker wire, threw in a bolt with some lock washers and nine months later it's still holding.

 

What a pain in the butt.

[GeneralDisorder]

Grade 2 is fine. You don't need real hard all thread for this job.

 

GD

[All4EA81]

What happens when the 7/16th's studs strip out? Cut the holes larger? This is what I was faced with but at the time I was about to install different heads anyway so I opted to helicoil the new heads with the stock 10mm threads as a preventative measure. Because at the time I had 3 different thread patterns holding the exhaust on, I was able to get all new matching studs from the dealership, including the self locking star head bolts for the exhaust manifolds "spacers". About $20 in all but worth it. I've had the exhaust off ten times since and with the help of some high temp lock tight I haven't had one stud ever budge.

[GeneralDisorder]

7/16x20 does not preclude using a heli-coil back to the stock size. You are actually removing LESS material with the 7/16" tap than you would be with the heli-coil's tap drill. It's also a lot less expensive, easier to source studs/all thread for the SAE size, and simpler for those that are more amature than us hardened vetrans of the wrench - it requires only hand tools and the tap - no drilling is involved as the 7/16 tap will cut using the stock metric hole.

 

The stock size studs can be cut from metric all-thread and the nuts are called "whiz-nuts" and are availible at any good hardware store. None of this stuff is unusual and if I'm going to the touble then I'm doing it right with stainless fasteners - not the crap from the dealer.

 

GD

[All4EA81]

Stainless is nice.

[Ginger48]

Stainless is nice.

 

When's the last time you priced stainless metric all thread? You had better be sitting down!

[MilesFox]

you can cut up all threads all day long if you already have the stuff laying around.

 

the thread size is m10x1.25 Typically this thread is harder to find in hardware stores.

 

You can buy studs at an auto parts store, maybe from a bin, but usually the pre-packaged "HELP!" brand in your typical Autozone type stores.

 

Look for 'import exhaust studs' or GM/Toyota exhaust kit. The latter will provide you with 3 studs and 1 bolt.

 

install the stud first, and when you do so the torque is applied to the stud once you put the torque on, vs a bolt that has to thread up first.

 

this will cost you less than 10 bucks. it should hold its torque until you take it out again. By then you still have the option of helicoil with proper thread without compromising the diameter of the hole.

 

The kits i have used have a nut that is tight on the first thread (hand tight), so you can install it like you would a bolt. It will instert the stud first before turning the nut.

 

Hope this helps you. good luck:)

[GeneralDisorder]

When's the last time you priced stainless metric all thread? You had better be sitting down!

 

Thus part of the reason for tapping it to 7/16. Cost and availibility are definitely factors here.

 

Metric anything is expensive here. Try to find anyone with metric thin-walled steel tubing. Last time we needed 6mm we had it shipped in from CA.

 

GD

[The Dude Abides]

I have a fine thread tap but would you say the thicker version would be better.

[All4EA81]

I've had better success with coarse thread taps in aluminum.

[GeneralDisorder]

I use 7/16x20, which is an NF size (fine). I haven't had any problems with any of the one's I've done.

 

You probably have the same size, but beware - there are other "fine" thread pitches out there that aren't 20. They aren't common, but you should refer to the actual TPI number as there are half a dozen different "fine" pitches out there in 7/16.

 

GD

Edited January 10, 2010 by GeneralDisorder

[The Dude Abides]

7/16x14 is the tap size i have. Should this do the trick.

[GeneralDisorder]

Yeah - 14 TPI will work as well.

 

GD

[The Dude Abides]

And i need to thread this as far as i can into the head.

[GeneralDisorder]

I always make a bottoming tap by cutting the tapered section off of an inexpensive tap to get at the last few threads in the hole. Not entirely neccesary but every thread you can get adds strength.

 

GD