Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Exhaust Bobbins

Some advice please.

I noticed I had one bobbin that had failed on my exhaust, so I decided to replace all 4 (4 came in the pack). Problem is I must of disturbed the seal from the main Librands exhaust where it clamps onto the front pipe / manifold

When holding my hand over the joint I can feel it blowing very slightly. The blowing / leak is coming from the slots on the exhaust. Even when sliding the U bolt clamp back or forwards, trying it in different positions, but it still leaks from the slots.

Can I apply exhaust paste over these slots without having to pull the exhaust apart? Or can I apply exhaust Paste with a jubilee clip over the slots maybe ? Or should the exhaust be pulled apart and apply the paste inside then bolt up. Im trying to avoid removing the exhaust if possible, and I’m not sure how good this paste is?

It’s only noticeable when you put your ear close.

Any advice is most appreciated

Craig

Craig, to do it properly you need to part the joint and apply the paste on the inside of the pipe. I can't see applying paste from the outside doing anything. Of course you could wrap it and use a clip as you suggest but it's a bodge and will look like one. Sometimes the joint is 'sprung' and once you loosen the u clamp it opens up a bit so you might need to push the two together as you tighten it. If that makes sense. I've also found that the pipes can be too loose a fit especially if of different origins.. I've cut a thin strip from a coke can or similar to use within the joint as a fix.

Thanks Steve, I won’t accept a bodge job on my Morgan so I will get it done properly.

Craig, I think your subject is very important. If the Sigma has a leaky exhaust and no matter how low it is, it loses a lot of power at high revs. I had exactly the same problem as you have today for years. The notches on the follower tube were cut too long. No matter where the exhaust clamp was fixed, it remained leaky.

I'll take pictures of my solution tomorrow. My local exhaust guru, who also built the manifold for me, replaced all connections with flanges. First without gaskets, which was not good but now with additional gaskets. I can highly recommend you to replace the pipe connections with flanges. Only if everything is really sealed the Sigma engine has full torque and full power at high speeds.

I had a very effective transitional solution before the flanges were made. There are self-adhesive aluminium tapes that can be wrapped around the joints. Then you screw the classic exhaust clamp over it. But the flanges are much more stable.

Thanks Heinz

Whilst you are in Bobbin Mode, worth checking the bobbins under the rad, just found one of mine sheared, easy job no need to remove rad just lift it a bit and they go in.

Advice taken Steve 👍, I used an additional U bolt and a jubilee clip.

My car does not look so pretty clean after our last Italy tour but you can see the pipe connections.







and the manifold



Temporarily, I can recommend the self-adhesive aluminium tape, which has lasted longer than one year.
I couldn't do anything with exhaust pastes because the notches at the end of the last tube were too long. It always blew through the too long notches.

Now that IS a proper job,Heinz.

Tony