- This topic has 14 replies, 4 voices, and was last updated 10 years, 8 months ago by
.
-
Topic
-
Hi Eric and Group-
Two questions, 1997 Saturn SC2 1.9 L DOHC, MFI, 5 sp manual trans:
I was advised not to do my leak down test until after I replace my faulty (rusty, leaking) exhaust system. What are your thoughts?
Is a hacksaw going to be enough to cut the old rusty system out?
I have watched Eric’s vids on exhaust rattles/muffler replacement/using torch. Is there any additional advice on this task you could offer?Thanks in advance for your response.
PS I gotta tell you Eric, you made me laugh (exactly when I needed it) with your new word-turbochargedhyperdriveness, LOL! Can I find that in Webster’s Dictionary? Thanks for that vid! 🙂
-
Replies
-
[quote=”lar1969″ post=95884]
I was advised not to do my leak down test until after I replace my faulty (rusty, leaking) exhaust system. What are your thoughts?I assume this is because any compression leakage past the exhaust valve might not be heard at the tailpipe because of leakage in the exhaust system itself, so this sounds like good advice.
Is a hacksaw going to be enough to cut the old rusty system out?
If you are sure you have room to swing the saw, then good luck to you. Use a fine tooth blade otherwise it’ll jam. If I were you, I would buy or borrow an angle grinder, as you may need to cut out bolts and it’s just easier and quicker. Also, yanking back and forth on the exhaust as you saw it may crack the manifold.
I have watched Eric’s vids on exhaust rattles/muffler replacement/using torch. Is there any additional advice on this task you could offer?
1. The night before the repair, get under the car with some safety glasses on and wire brush all the relevant bolts and spray with penetrating oil.
2. If a bolt starts to cause trouble, use heat again or cut it off. Don’t struggle with it – your knuckles will thank you. With that in mind, a set of suitable nuts and bolts for exhausts might be a handy thing to have ready.
3. I think this was covered, but it bears repeating. Assemble the new exhaust on the car loosely and ensure it’s clear of the chassis/body before tightening any clamps fully.
4. Afterward, get someone to hold a rag over the tailpipe with the engine running while you check for leaks.
[/quote]
My wife had a firebird, dual exhaust, 403 engine. She used this to drive to work – two miles – or for shopping. Doing this she’d rust an exhaust system out every year. I had the same car (we had two) and I replaced the exhaust on it once in 14 years of ownership.
For a long time all I had was a hacksaw. You had to be inventive but it got the job done. Then I got an air chisel. Much better.
Toss it out in chunks from under the car and preserve the mounts.
And, yeah, safety glasses are a must.
Thank you LandRover for taking the time to offer your advice.
I hadn’t thought of protecting the manifold from damage. Thanks! Also, I’ll look into an angle grinder.
I began the penetrating oil treatment of the fasteners last night and this morning. Will continue through out the day.
Save my knuckles, good point (as my fuel line/fuel filter replacement did a number on my hands)!
New set of fasteners, thank you. Will see what is coming with my kit. Probably should pick up some anti-seize to go on the new fasteners in case I need to tear into it again in the future.
Assemble loose, yes covered in the vids.Thanks, again!
[quote=”barneyb” post=95890]My wife had a firebird, dual exhaust, 403 engine. She used this to drive to work – two miles – or for shopping. Doing this she’d rust an exhaust system out every year. I had the same car (we had two) and I replaced the exhaust on it once in 14 years of ownership.
For a long time all I had was a hacksaw. You had to be inventive but it got the job done. Then I got an air chisel. Much better.
Toss it out in chunks from under the car and preserve the mounts.
And, yeah, safety glasses are a must.[/quote]
So short trips do a number on the exhaust too?
Hacksaw is all I currently have.
Safety glasses-Check. Kept mine from my lab days 🙂
Cut out in chunks-check. Hopefully the mounts are still in good shape…My parts guy mentioned something about welding (and to be quite honest, I got a little nervous). Did he mention that because I might experience mount breakage during this replacement?
Thanks for your response.I just thought of something else-
I don’t have an angle grinder but I do have a drill. I wonder if I could get a cutting attachment for it?
Looking into that now.
Any comments, please share. ThanksThe exhaust should have no effect on the leak down. You might have trouble hearing a leak at the exhaust, but if there’s a big enough leak I’m sure you’ll find it even with a leaking exhaust.
If a hack saw is all you have, it’s all you have. You’ll be working very hard though. I wouldn’t try a cutting attachment for your drill. That could get dangerous. It’s hard enough working under a vehicle on the ground. It’s quite another with a high speed cutting tool in your hands. With the hack saw you can just cut it out in pieces and install new parts. Hardest part will likely be getting to those old fasteners. Before you commit to that though, just call around to see what you can get it replaced for. Sometimes you can have an exhaust system (albeit a cheap system) installed for less than you can put one in yourself.
[quote=”EricTheCarGuy” post=95923]The exhaust should have no effect on the leak down. You might have trouble hearing a leak at the exhaust, but if there’s a big enough leak I’m sure you’ll find it even with a leaking exhaust.
If a hack saw is all you have, it’s all you have. You’ll be working very hard though. I wouldn’t try a cutting attachment for your drill. That could get dangerous. It’s hard enough working under a vehicle on the ground. It’s quite another with a high speed cutting tool in your hands. With the hack saw you can just cut it out in pieces and install new parts. Hardest part will likely be getting to those old fasteners. Before you commit to that though, just call around to see what you can get it replaced for. Sometimes you can have an exhaust system (albeit a cheap system) installed for less than you can put one in yourself.[/quote]
Good point-high speed tools under vehicle potential danger.
Having it done for me is not really an option as I am short on cash but have lots of time. 🙁 My 01 SC2 needed a new system a couple years ago and that costed $600.00. I could call around though. Never hurts.
My next question, which is related to this, would be: How is back pressure related to engine performance and are these 2 effected by my leaky exhaust system?
The exhaust mounts might break off but the ones that do are usually attached to the exhaust itself. Your new system will, of course, have its own mounts. If a body mount does break off, and you haven’t the money to repair it, (purists cover your ears), you can get creative with some mild steel wire and hang it till you get some funds in. This will pass the annual MoT test (inspection) in the UK, albeit with some rude comments.
Drills with cutting wheels can get a little jumpy, and are usually too small to get through a whole exhaust pipe. You’d have to work the wheel all the way round and probably won’t have room.
Angle grinders are so useful that I’d invest in one if I were you. Over here you can buy a cheap one for around £20 that will do the job.
“So short trips do a number on the exhaust too?”
Yes it does. One of the products of combustion is water. If you don’t drive enough to get the exhaust hot the water condenses in the pipes. And there is stays rotting out the metal that used to be used for exhaust. Dual exhaust makes the problem worse.
If I had a choice between SS exhaust and a powerful overhead cam engine I’d go for the exhaust every time. SS exhaust is a wonderful thing.
It’s not so much back pressure as O2 sensor readings. If you have a leaking exhaust it can allow excess O2 to enter the exhaust system. If this happens and the O2 sensor picks it up, it can upset the fuel trims and possible cause performance issues.
BTW, don’t bother with WD-40, use a good penetrant like PB Blaster or something to help with rusty nuts and bolts. Nothing works as good as heat though. It would be best if you could track down a friend with a torch.
Thank you for your response, Eric.
PB Blaster is the only thing, currently, I use for rusty fasteners.
I really need to learn more about back pressures though. It is a term I was introduced to this past weekend when I visited my local shop.
Yeah, I need to get a hold of a scanner so I can look at the fuel trims(been watching/learning more about the topic from your vids with “Scanner Danner”).
…thought I had a propane torch around here somewhere. :unsure: That might generate enough heat?
Found some info from a Honda forum dispelling the myth that Hondas need back pressure (when choosing an exhaust upgrade).
I thought it might make an acceptable introduction to exhaust theory/basics. What are your thoughts?
http://www.automotiveforums.com/t943495-backpressure_the_myth_and_why_it_s_wrong_.html
- You must be logged in to reply to this topic.