M54 3.0i Exhaust Gasket Replacement at Catalytic Converter

[andrewwynn]

I believe I use my 3/8 stubby impact to get the seam bolts off of the E 92 I worked on. come to think of it though I think two of the four bolts twisted off I did replace all the bolts. if you use hardware store bolts make sure you get hardend ones.

The advantage of the hardware store bolts was I got slightly longer ones and that was much easier to get them online because the exhaust pipes love to be bent where you don’t want them. I had to redo that connection because it was in the way of changing the transfer case

[richardb]

Thanks for the additional tips. My two year old Husky air compressor appears to have died after using it maybe 3-4 times ever! Junk. That being said, I can't use my Ingersol Rand 1/2'' impact gun until I buy a new air compressor.

This battery impact driver looks decent, 300 ft-lb of torque.

https://www.homedepot.com/p/RYOBI-ON...261K/313581565

May also grab this inflator/digital tire gauge as well, seems very useful for only $20.

https://www.homedepot.com/p/RYOBI-18...737D/307627867

[andrewwynn]

More expensive but look at the M18 series of impact. Actually I have my original high torque model I would be open to selling. 1100/760 ft·lb of torture (I typed torque but the autocorrect also fits). Ive stretched a few bolts with the sucker. I bought the 1400/900 ft·lb model to upgrade.

[oldskewel]

Originally Posted by andrewwynn

More expensive but look at the M18 series of impact. Actually I have my original high torque model I would be open to selling. 1100/760 ft·lb of torture (I typed torque but the autocorrect also fits). Ive stretched a few bolts with the sucker. I bought the 1400/900 ft·lb model to upgrade.

I wouldn't ask this of many people, but I expect you can give a good answer ...

What is the difference between those two torque ratings for the same tool? How can nut busting / breakaway torque be 50% or more higher than "max torque"? The tool is symmetric. Is there a difference in rating methods such as how long they'll hammer on it? Do they rely on heating of the part due to installation? So they install a nut to 1400 ft-lb, and while it is still hot from that, break it loose and declare victory?

I don't doubt that it's true, since everyone uses two different numbers. I just want to understand.

BTW, I've got a bunch of DeWALT tools (for example, spent most of yesterday using my DeWALT XR 20V Chainsaw = amazing), and picked up some really nice impact wrenches a couple of weeks ago. Their 899 1/2" with about 700/1200, I think, with bag, charger, and 4 Ah battery for $200. I think both HD and Lowes have this same deal.

https://www.homedepot.com/p/DEWALT-2...99M1/206387892

But I might not use that one since the smaller 894 1/2" is so powerful at about half the weight. Rated 330/600, really cool precision mode where for example it will pause for a half second before impacting - so you can release the trigger if you don't want it to impact. And the trigger is so smooth and controllable. I'll probably use this for 99% of things I do, and have the air impact for when that won't cut it. May end up gifting the 899 now that I see how good the 894 is. Half the torque, half the weight, same price, LOL.

https://www.lowes.com/pd/DEWALT-XR-2...nch/1000404679

[richardb]

Wow, that is powerful. Three times the power (900 ft-lb) is also three times the price ($300) but not sold in stores around here in Connecticut.

Might try the $100 version out, if it is weak, return it and buy another air compressor.

[andrewwynn]

Originally Posted by richardb

Wow, that is powerful. Three times the power (900 ft-lb) is also three times the price ($300) but not sold in stores around here in Connecticut.

Might try the $100 version out, if it is weak, return it and buy another air compressor.

Milwaukee sold at home Depot. Also same or next day with Amazon.

I bought mine specifically to remove axle nuts. I changed two bearings on wife's car and was able to remove with long pipe on breaker bar but I learned a trick to not break the breaker bar (which I have done a few times) and that is: use 1.5–2" PVC pipe not metal for extending a breaker bar. You can tell by the deflection when you are about to break the tool.

Anyhow the high torque tool couldn't even take out my caliper bolts the other day (because extension required to fit in acts as a torque stick) I had to use breaker bar and a hammer. Kicking it old school.

I finally bought the tool to do subframe bushings and after years of thumps and bumps from back I can finally replace them. Why I bring up is if memory serves the exhaust is right in the way so I either have to re work the same joint you are describing to remove most of the exhaust or get creative bending the welded hangar out of the way to drop the rear and risk damage to the same joint by leaving it attached.

I will of course report which route I take.

[Effduration]

I love my Kobalt (Lowes) 24v impact guns.. Maybe 2 years ago, I got two guns(1/2 & 3/8), two batteries, and a charger for like $250..Online coupon, etc.

the 1/2 Kobalt impact gun I have has 650 ft lbs of torque.

I know they are pricier now, but I would recommend them.

[richardb]

Originally Posted by Effduration

I love my Kobalt (Lowes) 24v impact guns.. Maybe 2 years ago, I got two guns(1/2 & 3/8), two batteries, and a charger for like $250..Online coupon, etc.

the 1/2 Kobalt impact gun I have has 650 ft lbs of torque.

I know they are pricier now, but I would recommend them.

Funny you mention Kobalt, I was just looking at Lowes. They appear to have two versions both at $199 right now.

650 ft-lbs:

https://www.lowes.com/pd/Kobalt-24-V...ded/1000604927

1,200 ft-lbs:

https://www.lowes.com/pd/Kobalt-XTR-...ded/1002274076

[richardb]

Saw one Milwaukee available at Home Depot. I ended up trying the $99 Ryobi with 300 ft-lb of torque on my E32. The wheel bolts are stuck on! Jumping on breaker bar didn't work either.

The $99 Ryobi didn't do the trick for the wheel bolts, so I returned it. Drove further out to Lowes and purchased the big daddy XTR Kobalt gun for $199. Overkill for exhaust studs, but should be good for wheel/tire changes.

All of this run around due to my air compressor failing.

[richardb]

That DeWALT looks nice too, a bit more compact than the XTR Kobalt I just purchased. The Kobalt did the job, barely. It has the same specs approximately, however the Kobalt as a 5-year warranty vs. DeWALT's 3-year, which is nice.