Raspy exhaust?

Went on a nice long drive today, and took a couple of friends to Fareham to do some shopping. It's been a nice sunny day today, and all the classic cars came out of the woodwork. We saw a huge 1960s Cadillac, a Pontiac Trans-Am, two '65 Mustangs, a Porsche 356 Carbriolet, a Reliant Scimitar, a Cortina mk.2 and a Beetle. My Moggy made the trip faultlessly, although on the way home I noticed it had developed a rasping noise coming from the engine whenever I stepped on the gas. At home I opened the bonnet and inspected further, and I found there was an irregular but constant "chuff-chuff" noise coming from the area around the carburettor and the manifolds.


I suspected at first a leak from the exhaust manifold, and hoped it was nothing to do with the carburettor, since I don't know much about them and they're expensive to replace. I've just gone onto the Young Members facebook page and asked their opinion, and I've been told it is indeed an air leak, probably from the point where the exhaust manifold joins onto the top of the exhaust pipe. This actually makes a lot of sense, since that was the part that Sean at Sussex Classics had to wrangle with to stop the exhaust pipe knocking against the bodywork. There's a lot of white sealant all over the join, and I've been advised to strip away the old stuff and re-seal it. How I'm going to get the old sealant off is a mystery to me; chipping away with a screwdriver I presume. Luckily there's a local motor factors and a Unipart store within walking distance of my flat, so getting some new sealant should be fairly easy. I think first the priority is to ascertain as to whether the leak is coming from, and I really hope it is that joint. I'm pretty sure it's not the inlet manifold, as that would put extra air into the cylinders and make the car run funny. However, if it's where the exhaust manifold meets the block, It'll mean a lot of work with spanners and some new gaskets. Not that complicated, but fiddly and time consuming.


It's not like the car's any worse to drive, but exhaust leaks are an instant MOT failure, since the gasses can get into the cabin; not good. What's more the rasping is irritating. It is pretty annoying this happened now; I've just bought a new Jago Jeep for a bit of restoration, and I was going to go home and see it for the first time tomorrow. With a leaky exhaust however, a 100 mile drive doesn't seem very sensible. Hopefully I can have this sorted out by the end of tomorrow.