Looking to save an original 69 L71 pass side muffler

[Chris H.]

My 15,000 mile car has its original exhaust system which sounds great. Unfortunately the pass side muffler, where the tip meets the muffler, has some corrosion and that connection is week. The seem is also corroded. Any ideas on how this muffler might be saved? Possibly some fancy sheet metal work? Thanks, Chris

[Joe L.]

Re: Looking to save an original 69 L71 pass side muffler

My 15,000 mile car has its original exhaust system which sounds great. Unfortunately the pass side muffler, where the tip meets the muffler, has some corrosion and that connection is week. The seem is also corroded. Any ideas on how this muffler might be saved? Possibly some fancy sheet metal work? Thanks, Chris

Chris------

The most common location for corrosion to occur and render these mufflers scrap is where the rear pipe connects to the muffler. You should check yours carefully in this area. An ice pick or similar sharp, pointed tool can be used to probe this area.

In any event, if you have corrosion that has weakened the area between the rear extension and the muffler the chances are great that there is much more corrosion inside the muffler. Repair of such is impractical.

[John M.]

Re: Looking to save an original 69 L71 pass side muffler

Chris, if the pipe and the muffler innards are not corroded and it's only rusty at the weld you can replace the tip(s). Carefully grind away the weld to remove the tip and then assess whether or not the pipe and innards that you can see are ok. If not, as Joe says, forget it. I just did two tips on G M service replacements from late 70s that are ok inside with surface rust on engine pipe side so there may be a chance.
John

[John M.]

Re: Looking to save an original 69 L71 pass side muffler

Whoops! Read it wrong Chris. The ones I fixed were 65s. Sorry.
John

[Joe L.]

Re: Looking to save an original 69 L71 pass side muffler

Whoops! Read it wrong Chris. The ones I fixed were 65s. Sorry.
John

John------


The 1965 muffler set-up is pretty much the same as 1969. However, all 1969's were 2" whereas for 1965 only 250 HP and 300 HP with Powerglide were 2". Nevertheless, the outlet side of the 2" and 2-1/2" mufflers is the same. Outlets on both mufflers are 2".

[Terry M.]

Re: Looking to save an original 69 L71 pass side muffler

I know of one case where original passenger side 1968 under car off-road muffler was saved by a very experienced welder. He rebuilt the whole back wall of the muffler and the only way we knew was he told us. It can be done, at least in one case, but it takes a lot of skill. The individual who did this work has since passed on. Good luck finding someone with those kinds of skills.

[Chris H.]

Re: Looking to save an original 69 L71 pass side muffler

Thank you all. Can I just get new mufflers and have them welded on to the original pipes? Is this something a competent exhaust shop can do? Or do I have to get an entire system? I'd really like to keep the original pipes on the car if possible as they are not corroded at all. Thanks, Chris

[Joe L.]

Re: Looking to save an original 69 L71 pass side muffler

Thank you all. Can I just get new mufflers and have them welded on to the original pipes? Is this something a competent exhaust shop can do? Or do I have to get an entire system? I'd really like to keep the original pipes on the car if possible as they are not corroded at all. Thanks, Chris

Chris------


SERVICE mufflers have an extension on them. To install, the old muffler and a length of the original pipe equal to about the length of the extension on the SERVICE muffler is removed. Then, the slip joint on the SERVICE muffler extension is inserted into the cut-off end of the original pipe. So, most of the original pipe is retained. If one purchases a replacement pipe, it will be "pre-shortened" to work with the SERVICE muffler and its extension.

Can you have the extension on the SERVICE muffler removed and the original pipe, unshortened, welded directly to the muffler? I suppose it could be done but I would not recommend it, at all.

[Chris H.]

Re: Looking to save an original 69 L71 pass side muffler

Thanks Joe. So would that service muffler replacement connection be a clamp or a weld? I'd like to avoid using a clamp. Chris

[Joe L.]

Re: Looking to save an original 69 L71 pass side muffler

Thanks Joe. So would that service muffler replacement connection be a clamp or a weld? I'd like to avoid using a clamp. Chris

Chris------


It can be either a clamp or a weld---your choice. However, even if welded, the configuration of the "finished product" will not be as-original due to the slip joint.