Exhaust gasket is good and just bolts rusted away?

[rogerranger2122]

2015 Honda Pilot EX-L 6 cyl 3.5

loud from an exhaust leak.

It seems only the bolts rusted away? Or is there a missing gasket/flange?

When I enter this car to autozone's site looking for exhaust flange, it shows a diamond/pointed silvery type gasket that looks like it might have deteriorated away but then I click on it and it just shows metal rings which seem to both be existing fine on both sides of the pipe. This is right after the cat.
I found no videos or anything about this year Pilot to confirm anything. Most others have a coned shaped flange that allows some flex besides what the flexpipe allows.

Just bolt it back together? It seems there should be something more sealing that this. Maybe just use cut/sheet high heat type gasket or a paste? If autozone doesn't carry these exact bolts I might just use hardware store , then rust preventer paint and a couple topcoats to prevent more rust. Only this section basically is rusty. thanks.

[rogerranger2122]

https://imgur.com/cZNAFLK

https://imgur.com/NNMqP9d

https://imgur.com/A52ThyX

[Stealthee]

It should just be a donut gasket. If it were me I'd replace the gasket and probably torch out the old studs and replace with bolts.

[rogerranger2122]

thanks for reply.

still confused. Can anyone link a diagram that actually shows what part #s belong where so I can confirm if a gasket or something rusted away?

The 3 rusted bolts coming from the cat, I'm hoping to keep and not make a bigger project by grinding and drilling them out, torching etc, I do have a torch but just propane and had a rust box ranger that every little thing I needed to do became a big project because of stubborn rusted bolts, so I'd rather not mess with it - if the bolts rust away or break then I'd try replacing them, or even the whole cat.

all replies I've gotten so far from different sources:


It should just be a donut gasket. If it were me I'd replace the gasket and probably torch out the old studs and replace with bolts.

-----------------------------------------------------------------

Often times a dealer parts dept can be cheaper than aftermarket places. Replace the bolts with what you can source locally and here's a link to the gasket you need.
Gasket, Pre Chamber - Honda (18393-SDB-A00)
https://www.buyhondapart.com/oem-par...bC12Ni1nYXM%3D

Best thing to do is clean all remaining gasket material on both sides, and install new gasket. Considering the amount of rust there, an exhaust sealing paste probably wouldn't be a bad idea on both sides of the new gasket, just depends how pitted the mating surfaces are.

Good luck.

-----------


From what I see there you have no studs left that are in usable condition.
You'll need to grind off flush on both sides the remainder of what's there, drill out the centre to go thru the remaining weld, knock out the leftover stud, install 2 fresh nuts & bolts, install the new gasket.
You may need some heat there as well, so an oxy/acetylene set or Mapp gas kit would be needed.

+++++

^^^ yes.
You can get gasket material specifically for this situation and cut your own if necesary.

-------------------------

[maxwedge]

At this point you should try to look at parts guide at a dealer or online.

[rogerranger2122]

done,
but the other 3 nuts on the other side of the cat are probably going to rust away soon.

Thanks to the genius head of design at multi trillion dollar company Honda (and others..) for choosing to save like 12 cents on production costs of a $38,000 SUV by using these grade bolts to rust away easily.
I replaced them w grade 8 yellow zinc should last the lifetime of the car but the other side at least I have the technique down now if I have to do those later. Took damn near all day crawling under there etc (I hate wrenching on anything jacked up or on ramps so I crawl under truck/suv for this. Angle grinder cut off wheel wouldn't fit without hitting important metal tubes etc, ordering metal blades for my multi tool tomorrow which was useless for the wood/plastic/soft metal blade, have all the other masonry etc types but not for serious metal cutting. $6 harbor freight dremel tickled it, waste of time, need to upgrade that. Had a worn down small angle grinder cut off wheel that worked though. Sawsall metal blade mighta worked too. Even M42 cobalt drill bit with cutting oil didn't go so quickly, luckily successfully re-sharpened it on bench grinder first tries which is tricky, although the 30 min tutorial videos on that should basically just say keep 1 bit and don't use it just use a reference and grind the dull one to match it.


As for the mystery gasket, you can see in first pics there is remnants of something there, either some sorta thin metal sheet that deteriorated or I think they might have just used paste sealant at the factory. Parts diagram linked, on left , does show uses 18393-SDB-A00 which looks like a rounded metal ring when google for an actual image despite in photo you can see both sides have flat metal rings even if this ring is soft lead I don't think it'd compress that flat. Doesn't hurt to add the exhaust-grade gasket that I did. Autozone shows existing flat metal gasket in system but metal on metal seems dumb, have worked on many small engines never seen anything like that let alone for the exhaust of an SUV so I traced the hole and bought the closest match gasket from a random car (autozone doesn't carry cut-sheet exhaust grade gasket), holes don't line up but doesn't matter, kept it in place temporarily with a dab of caulk and bolted up.

Rust reformer painted the other side too hopefully slows the rust. Will topcoat later when have to stainless wire/hose clamp the heat shield back on which bolts rusted also. great.



https://imgur.com/a/839pyTZ
2 pics scroll