Hi, I recently installed genuine ford silencer to my aftermarket exhaust middle pipe. It seemed fine for a few days but then I noticed a high pitched noise from the back of the vehicle after driving for 20mins. I have reinstalled the silencer few times and got new clamps but the noise is still there. My assumption is that the expansion rate of those two metals are different and that’s what causes a gap to form when the car is heated up. 
 

is it possible to weld the slip-on joint between silencer and middle pipe? I’m in Warwickshire so it would be great if there’s any recommended workshop for this welding. Thank you 🙂 

What sealing compound did you use between the joint ?

5 minutes ago, unofix said:

What sealing compound did you use between the joint ?

I used the holts firegum tube on the left. But it doesn’t seem to hold two pipes in place after I assemble them. 😞 

Double check there is a good amount flow going out the back incase its collapsed inside somehow, could be back pressure building up as apposed to a leak as such.

Unusual for an exhaust leak to cause a high pitch noise.

2 minutes ago, JB0702 said:

But it doesn’t seem to hold two pipes in place after I assemble them.

It won't hold them in place but after you coat the pipe with the compound and push it inside the other one and secure it with a good 'D' clamp there should be no way it can move or leak.

Didn't read that bit ☺️

5 minutes ago, unofix said:

It won't hold them in place but after you coat the pipe with the compound and push it inside the other one and secure it with a good 'D' clamp there should be no way it can move or leak.

I have two clamps holding the pipe down now but I will try to reinstall it with more paste tomorrow. Hopefully I can seal the gap! Thank you 🙂

6 hours ago, unofix said:

It won't hold them in place but after you coat the pipe with the compound and push it inside the other one and secure it with a good 'D' clamp there should be no way it can move or leak.

I have realised that the outside diameter of the middle pipe is much smaller than the inside diameter of the silencer. They don’t seal properly even though how hard I tighten them. 

So I am thinking of getting this aluminium foil tape to wrap around the middle pipe then use copper gasket maker to seal the remaining gap. I know the ashensive will melt but I don’t think it will be an issue. What do you think about this method? 
 

thank you! 

I think you will possibly get away with just the foil tape and a covering of the sealing compound.

You don't want it to look too much like an bodge job or it may draw unwanted attention from an MOT tester in the future.

Looks like you got the wrong silencer if the mismatch in diameter is as big as it sounds.

16 hours ago, unofix said:

I think you will possibly get away with just the foil tape and a covering of the sealing compound.

You don't want it to look too much like an bodge job or it may draw unwanted attention from an MOT tester in the future.

I think I finally fixed it! Wrapped the foil tape around the middle pipe and used assembly paste to secure it. I will wait until tomorrow and see if it worked or not 🙂 

5 hours ago, agraham said:

Looks like you got the wrong silencer if the mismatch in diameter is as big as it sounds.

The difference in diameter was 2mm. Maybe the after market middle pipe has a diameter that’s too small. But seems like I fixed it for now so I will see 🙂 

I gave up, called up a welder and he said £20 for welding the pipe up so I will get it done this weekend. 😂