Replacing both catalytic converters
#1
08-08-2018, 12:47 PM
Replacing both catalytic converters
I知 having a nagging P0420, and I知 noticing a few other codes that support the need for a cat replacement. The codes as well as a white discolored cat and surrounding pipe. So I figured signs are good that one is failing and I bet the other one is not far behind. So I ordered the SS magniflow cats and will be replacing them over the weekend. I also have short headers and an aftermarket muffler (no idea of brand, was like that when I got it). Anyway on to my question. You folks think I should replace the exhaust manafold gasket while I have the cats off, or no need to? I am not aware of any leaks. But if I were to do it I guess this might be a good time.
Im going to start spraying the bolts today with some PB blaster to help them play nice over the weekend. Any other tips or thoughts?
Im going to start spraying the bolts today with some PB blaster to help them play nice over the weekend. Any other tips or thoughts?
#2
08-08-2018, 03:01 PM
Totally replace the gaskets, you only want to go through this once, they are not expensive and the risk of a leak with an old gasket is high.
#5
08-08-2018, 09:06 PM
You'll be lucky if there aren't a couple already broke off,
on the LS I would leave things alone if they aren't leaking as they are known for broken manifold bolts.
If you do decide to tackle the gaskets be prepared to deal with broken bolts.
Neal
on the LS I would leave things alone if they aren't leaking as they are known for broken manifold bolts.
If you do decide to tackle the gaskets be prepared to deal with broken bolts.
Neal
#7
08-09-2018, 07:40 AM
If you have headers and plan to replace the header gaskets but good GM gaskets and replace the bolts with these:ARP 4341301 Header Stud Kit for Chevy LS1
Many of us here have used them and I haven't any issues since.
Many of us here have used them and I haven't any issues since.
#8
08-09-2018, 08:32 AM
NoSpoon. I have them on the list. I知 still trying to decide if I should try to replace them, or the gaskets. I am not aware of a leek, and I have no broken bolts. I知 afraid if I try to remove the bolts to swap gaskets that the bolts will snap and then I値l be stuck with a how to repair situation. My ICD wants me to replace the bolts and gaskets while I知 in. But my logical thoughts are if it ain稚 broke... don稚 fix it.
#9
08-09-2018, 08:49 AM
myrddin,
If you don't have any leaks then you may be good. I had a couple that were broken so when I installed headers and cats I did them at that time. Fortunately the 2 broken bolts left enough sticking out to grab with an extractor tool. If and when you do these remove the plastic inner fender wells, takes 5 minutes and makes everything easy to reach.
Good Luck!
If you don't have any leaks then you may be good. I had a couple that were broken so when I installed headers and cats I did them at that time. Fortunately the 2 broken bolts left enough sticking out to grab with an extractor tool. If and when you do these remove the plastic inner fender wells, takes 5 minutes and makes everything easy to reach.
Good Luck!
#10
08-09-2018, 09:05 AM
Thanks buddy! So would you say that if the bolt heads are all there that I should keep as is? And if that痴 true would you say to keep an eye on them and if one of the bolt heads break then it痴 time to go in and replace all the bolts and gaskets?