Removing Exhaust Bolts

[Adam Ef]

I'd definitely recommend a few rounds of a good amount of heat from a quality blow torch, then quickly cooled with something like https://www.ebay.co.uk/itm/WURTH-ROS...item2cd367c6c9



Just in case they don't come out, here's what I bought that worked...
https://www.ebay.co.uk/itm/232570119279


You'll likely kill them all doing the job, but they're a lot cheaper than a strip down. Centre punch to mark the centre, then a starter dill bit if you have one... then the left handed set worked the way up in size, on a slow speed preferably with cutting fluid on the bit regularly too.


Then a tap of the right size to clean up the threads once you have them out.


Good luck.

Thank you for that Adam Ef,

It may be that the bolts just come out and all this comes to nothing, but I might as well prepare as best I can.

I think the one on the left side (the one in the photo immediately above) will probably come out - it moved just a little when I tried it yesterday afternoon. I'll give it a good clean so I can see what is going on and warm it up with the butane torch.

[Adam Ef]

I thought that the one on mine that sheared was turning. That's why I went a bit fast with it and it turns out it was just the top that was turning. Hope that's not the case with yours. Only way to see is to just do it. Just do not use extractor bolts... ever! I repeat that quite a lot these days after my ordeal.


Hopefully you're lucky and they just come out without a fuss. Definitely good stainless bolts with grease on them when you reassemble.


(edit: it's impossible to know the history, if they've been removed in recent years they may be fine. Mine's a K8 and the gasket inside was not original so it must have come off at some point since new.)

[Bibio]

use a windygun..

Well chaps, I've had a really satisfying morn. Thank you for the advice, I used most of it (tapping the bolts, fire and water treatment, lots of penetrating oil - but most of all a a huge amount of patience) and got both bolts out. As you may see from the photo, there is almost nothing left of the manifold bracket, it has just been eaten away by years of hot, salty road crud:



There really was not much holding the pipe on to the head, so I'm glad I did this job, and glad I asked that question yesterday - thank you for your contributions.

The header pipe is off, and the port looks okay:



There is a little corrosion of the aluminium on the left, but the screw threads will be plenty deep enough. I didn't find any evidence of the gasket I've ordered - unless it is that sort of black ring sitting about 10mm inside the port? If so how do I get that out?

Alan

[Bibio]

well done. yup the gasket is still in there.

[Adam Ef]

Good news.


Have you got a dremel?


That ring inside may be a gasket (Aluminium sandwich type). Can you clean up the outside edge of it and check it's seperate from the block? If it is then chisel or dremel it out. I used my dremel a lot on this job. The replacement gasket I got wouldn't fit in without cleaning back the build up of crud and corrosion for it to slide in place. The grinding and poilishing bits worked really well in the tight working space.

Thank you for that chaps.

I have ordered replacement gaskets, but the ad says they are fibre, not aluminium. I'm wondering whether it is worth having to cut out the metal gaskets (and so risk damage) and replace them with fibre ones. I'm thinking it might be better to leave the originals in there (and perhaps reassemble with a smear of jointing paste).

It would only take half an hour to disassemble the new arrangement (once the new bolts arrive - tomorrow's post I hope) should the old gaskets not be sufficient.

What do you think chaps - the old seals certainly look fine.

Alan

[shiftin_gear98]

Bodge it and ride it.

If it leaks find lots of tunnels to ride through.
See if you are worried about it or something worse when the MOT is looming.

Oil all over the rear tyre is bad, a slightly blowing exhaust on a £600 pony. Up to you.

I'm waiting for the new bolts to arrive, but I thought I'd assemble everything loosely to make sure it all fits:



The new header pipe fits fine, and looks a great deal better than the old one. The really important thing is the manifold bracket has another 20 years' life in it so the pipe won't suddenly part from the head!

The tinworm had taken its toll on the front part of the middle section of the exhaust, where it meets the header. About 15mm crumbled away and I trimmed it away square with a file. The downpipe spigot is 55mm deep, so there will still be about 40mm of sealing depth and I have made a SS spacer to fill in the last bit and give the clamp something to bite on to. I did think about getting a replacement used middle section, but the ones I saw on eBay all seemed to have rotted a bit at the same place, so I'm guessing it is a common ailment.

I'm still thinking about whether I leave the aluminium seal in the exhaust port or cut it out and change it for a fibre one. I tending to leaving the original in there. It appears to be in good condition and I'm loath to risk more damage but cutting it out. Advice would be appreciated.

From being a bit despondent about the bike yesterday, I'm quite pleased with it now. I have it sorted apart from a few minor parts and final assembly, it looks fine, it has been a sunny day and the lambs are dancing in the fields.

Many thanks for all the contributions on this and my other recent threads.

Alan