How easy is it to find/fix an exhaust leak?

If the leak isn't obvious it may be a case of listening at the joints with some sort of stethoscope ( piece of rubber tube)..mine leaks ever so slightly from the manifold to head.
To be fair, since the carbs were balanced ( another potential cause of popping) it's all but disappeared.

 

Have a lie underneath first of all whilst someone gives it a bit of a rev - you may also notice black carbon marks where it's been leaking for a while, or you might be able to feel it puffing out if you hold your hand close by (don't get burnt). Even if you're not attempting the repair yourself, knowledge is always useful!

You'll either have a leak -

1. At the manifold, where the exhaust bolts onto the cylinder head, youll probably need to remove a couple of bits of tinware to see this
2. In the pipework / heat exchanger
3. Silencer (most likely one of the welded joints to the exhuast pipe)

 

An old plumbers trick.....



















Stick a potato in the end ..
and look for the hissing...

and you get a jacket potato for dinner...

 

Alex is not an "old plumber", she's a" Heating Engineer ".
Now apologise at once you rude boy.

 

RUDE BOY
RUDE BOY
RUDE BOY....

 

My mistake..

 

Get your glove on and stick your hand over the end of the exhaust pipe. The engine should slow down or even stop. If it doesn’t, likely there’s a leak or hole somewhere.

 

Engine off. Stick a smoke pellet up the exhaust. Blow the smoke up with a hair dryer. Look for where the smoke comes out. Just like testing a chimney

 

Don’t see why not. Exhaust gas leak can’t be that different to a smoke gas leak.

 

Try wrapping some PTFE tape round it

 

Meh..


a plumbob with a holed pipe..

 

I stick my hand over the tail pipe (whilst holding a suitable rag) and you’ll hear the leak ‘chuffing’.

I used the fit exhausts ‘dry’ but nowadays I tend to use a smear of exhaust assembly paste. I think the clamps and fittings are poorer quality than they used to be hence the additional measures.

 

I seem to remember you said it started popping after the garage did some work? If you have twin carbs, I strongly suspect the problem is a balancing one too. What carbs do you have, Alex?