Find leaks in heating system

I've managed to get my heating up and running again today but now I'm looking to improve the performance. I have to renew the cables to the heat exchanger diverters but I've fixed them open for the moment. How do I find where it may be leaking and what can I use to fill the leak? I have noticed a few areas of concern i.e. Heat exchangers where exhaust exits, joints to both sides of the elbows.

 

Use a mole smoke and hair dryer back from other end, smelly but you'll see them.

 

That is genius!

 

The biggest leaks my westy had were where the centre pipe had rotted through unseen inside the cross members. If you start it up and crawl under you should feel any leaks.

 

Brilliant, smoke bombs it is!!

 

They should also flush out any moles living in your heating system

 

What can I use to fill the leaks, gun gum?

 

Moleskin obviously...

 

Dont think it gets hot enough for gun gum to set properly.
Also if its rusty holes it will just rust a bit more and the gun gum falls out.

Depending where the holes are and what they are in you may need to add material to cover holes or replace entire tube sections. cover over with sheets of tin etc.
A bodge followed by a proper replacement when time and finance permits ...

 

http://www.sealantsandtoolsdirect.c...Jc06jLWb0eJI1Zitm_ULC__fYc6-MCERx4aAuNj8P8HAQ


something like this