depending on how bad . I have used the stuff called goop seems to stick very good and stays flexy. use it by itself for small stuff or reinforce as needed .good luck.
Hi,
dont laugh at me, i closed the old exit for the exhaust at a max II ( a big hole ) in this way:
I used an old trashcan which is made out of high density polyethylene (german trashcans are out of PE) and welded it wiht a hotairgun on the outside of the body.
From the inside i welded a special PE wire, which is specialy made for PE welding with such airguns around the edge of the hole. Like soldering or welding both parts need to be hot when pressed together.
Looked terrible but worked very well. Sadly i sold it later so i cant send a picture.
The only thing you have too look at is that there is no oil or grease and that the airgun did not get to hot, else the whole body is changing its shape.
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