MG TD Gets A New Exhaust

To be completely fair, this wasn’t a planned upgrade. More like a crime of opportunity.

After nearly completing the restoration and with winter setting in, I advised Bruce to “not take the TD on the road” until spring came and washed the salt and grit off the pavement. Part of my advice was meant to preserve the new paint and undercarriage but there were also a few odds and ends to complete under the car (one of which was to replace the broken mid-pipe hanger on the exhaust) and having it stay clean would be bonus when doing the work. What I hadn’t considered was that my words would be taken literally. Read on.

Pretty sure this isn't standard

Pretty sure this isn’t standard

One evening, Bruce and I were on the telephone discussing the TD when he conveyed that he thought there was something wrong with the car, suggesting that perhaps things were amiss with the engine. This just couldn’t be! I had checked the engine thoroughly—great compression, all new electrics, valves had been adjusted, timed it, everything—and it purred like a kitten, usually not even needing the choke to start. The first passably warm day we had, I made it over to the shed and started it up. The engine was just fine. The exhaust, on the other hand, was complete toast.

It seems that Bruce had been obediently not taking the TD on the road. The backyard, however, appears to have been another matter with a neat little track dug into the turf where he had been making laps in the TD. Without the mid-pipe hanger in place, the exhaust must have bounced up and down with the joint at the rear of the muffler acting like a hinge. Eventually it weakened to the point where the back pressure simply blew the rear of the muffler out.

All shiny and new

All shiny and new

A new stainless exhaust and hardware were ordered from Moss and Bruce started soaking the fasteners  in “knock it loose” so the disassembly could proceed. What a silly thought. 60 years of heat and corrosion were not so easily swayed and getting things apart into a battle of wills with brute force winning out in the end.

The bolts and nuts holding the down pipe onto the exhaust manifold would simply not budge no matter how much persuasion I used. To get the pieces to part would mean using a nut splitter and to do that meant I would have to remove the down pipe through the engine bay and to that meant having to remove the exhaust manifold from the block proper and separating the muffler and tail pipe from the down  pipe.

Liberated from down pipe

Liberated from down pipe

Like the header, the muffler and down pipe connection was corroded solid shut and to get them apart I ended up peeling the slip join material away from the pipe then using a few blows with a small hand held sledge to dislodge the muffler. After that, it was a simple matter of disconnecting the accelerator and choke linkages, removing the choke lever, removing the air cleaner assembly, then the intake and exhaust manifolds, allowing me to extract the fused header and down pipe up through the bay.

Once on the bench, I split the nuts off the connection and liberated the exhaust header.





For the most part, reassembly went as expected although I discovered the manifold studs included in the installation kit were useless because, at some point, the flange had been drilled out to accept a larger diameter bolt. A quick trip to the hardware store remedied the situation and the engine exhaust reassembly went smoothly from there on out. I ran into a little bit more corrosion related resistance when attempting to replace the broken mid-pipe hanger but a liberal application of solvent and some leverage broke the bolts loose.

Down pipe and muffler

Down pipe and muffler


Looking aft

I must admit that, while I like stainless steel for exhaust work, I’m not really a fan of the polished variety, feeling it was sort of gilding the lily. That said, the polished exhaust really does look nice and adds a bit of dress p to the engine bay.

New...from stem to stern

New…from stem to stern

With everything back together, I replaced the ground cable to the battery, pulled the choke out, and then the starter. The little TD motor kicked to life instantly. A quick check for exhaust leaks revealed none so I  shut the car down, put the fan exhaust tip back in place, and called it day. There’s still the matter of the missing down pipe hanger bracket (was missing from the parts kit) but, other than that, the new stainless system should be good for another 60 years when, the next owner may get the pleasure of not having to chisel things apart.







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