moparmat2000
Well-Known Member
Ok, so my daily driver Chevy HHR has had an exhaust leak for a couple of years. Start the car up and it would go away. Well it got progressively worse until now I got to keep the A/C on recirc so i dont die in the car driving it. The flex coupling on the down pipe aft of the exhaust manifold was cracking badly. Finally got so bad I had to replace the pipe. Air sucking in was messing with the O2 sensors so bad, it was trying to run pig rich as it kept sensing a lean condition.
Local muffler shop wanted $170 to cut and weld in just a new down pipe and flange. Same flange and flex coupling I could get off evilbay for $50. I was like ummm no. With 119k on the odometer the car prob could use a new set of converters anyways. I was able to get the down pipe assembly with the 2 converters, and fwd and rear flange all welded up and ready to go complete with gaskets and hardware in case my old studs and nuts were rusted solid for only $109 shipped off evilbay to my doorstep. Straight up RAR deal Part fit perfect. Took about 1.5 hours start to finish.
Now for the penetrating oil part. I am a big fan of heat it with a torch and mapp gas, then hit the bolt or nut with regular CRC or WD40, then try the wrench while it's hot. Heat and repeat until it comes loose. I bought this penetrating oil. Its either a new product, or just new to me. CRC chilling penetrating oil I got from Vatozone. It not only sprays penetrating oil, but it sprays it with an ice cold blast. I think the combination of the dry environment I live in, plus heating , then chilling the hardware down with this chilling penetrating oil combo was the reason I was able to get all the nuts off the studs on both ends without any damage to the studs and nuts. I used some antisieze on the studs, and reused everything hardware wise since the replacement stuff was bolts and nuts for if you have to drill out the studs and through bolt it.
Hope this helps
Matt
Local muffler shop wanted $170 to cut and weld in just a new down pipe and flange. Same flange and flex coupling I could get off evilbay for $50. I was like ummm no. With 119k on the odometer the car prob could use a new set of converters anyways. I was able to get the down pipe assembly with the 2 converters, and fwd and rear flange all welded up and ready to go complete with gaskets and hardware in case my old studs and nuts were rusted solid for only $109 shipped off evilbay to my doorstep. Straight up RAR deal Part fit perfect. Took about 1.5 hours start to finish.
Now for the penetrating oil part. I am a big fan of heat it with a torch and mapp gas, then hit the bolt or nut with regular CRC or WD40, then try the wrench while it's hot. Heat and repeat until it comes loose. I bought this penetrating oil. Its either a new product, or just new to me. CRC chilling penetrating oil I got from Vatozone. It not only sprays penetrating oil, but it sprays it with an ice cold blast. I think the combination of the dry environment I live in, plus heating , then chilling the hardware down with this chilling penetrating oil combo was the reason I was able to get all the nuts off the studs on both ends without any damage to the studs and nuts. I used some antisieze on the studs, and reused everything hardware wise since the replacement stuff was bolts and nuts for if you have to drill out the studs and through bolt it.
Hope this helps
Matt
