Engineering help req in Midlands

Help!

I need to replace the midsection exhaust on my turbo. The four allen
bolts that connect it to the turbo unit are seized solid and in fact
don't look like they've been moved since the bike was assembled in 1984.
In fact the midsection looks to have been welded while in place to
convert it from a two silencer system to one.

I'd have a go myself except any slip of the drill is going to be very
expensive as I can easily see the turbo housing being damaged and
they're incredibly expensive to replace.

Can anybody help? I can remove the turbo unit and exhaust in one lump
(by removing the headers), so it's portable, am happy to transport
anywhere within reasonable distance.

Suitable beer tokens/payment of choice of course.

 

To be honest looking at the bolts I think they're too far gone for heat,
and there's no way to get any decent purchase on them (the allen bolt
heads are also corroded and the allen key just turns inside them without
ever getting decent purchase, pretty resigned to grinding the heads off
and drilling.

The engine is a runner, but no petrol tank (being sprayed).

 

Blimey - not a single mention of rattle guns!

I vote for an autoclave & a large stock of carbon fibre.

--
Krusty.

http://www.muddystuff.co.uk
http://www.muddystuff.us
Off-road classifieds

'02 MV Senna '03 Tiger (FOYRNB) '96 Tiger '79 Fantic 250

 

Hammering in a torx bit can sometimes work for fucked allen bolts, when
assisted by a blow-torch.

--
Krusty.

http://www.muddystuff.co.uk
http://www.muddystuff.us
Off-road classifieds

'02 MV Senna '03 Tiger (FOYRNB) '96 Tiger '79 Fantic 250

 

Sorry, it seems I had a case of premature extract-suggestion[1].

And a surface grinder.

<sobs over shim bill>

[1] That doesn't really work does it.

--
Krusty.

http://www.muddystuff.co.uk
http://www.muddystuff.us
Off-road classifieds

'02 MV Senna '03 Tiger (FOYRNB) '96 Tiger '79 Fantic 250

 

I'll be trying various things once I actually get the damn thing off the
bike. Chance of success not high, which is why I'm trying to arrange
some help!

That Torx suggestion sounds good, so will be giving that a go.

 

Either way, you're screwed.
--
Dave
GS850x2 XS650 SE6a
Every post contains Nutri-Ceramide-R and Pre-Biotics
for your reading pleasure.
Folding@Home Team UKRM
http://vspx27.stanford.edu/cgi-bin/main.py?qtype=teampage&teamnum=47957

 

Torx or star. That's what I'd go for. Bits are cheap. Hammer in the
biggest, chunkiest one you can after you get the casing as hot as you
can. Then apply steady torque, after tapping the thing a good'un or
two wiv an ammer.

 

<awaits 'and then the casing split' post>

 

Well with a little help from Ginge I've been persuaded to buy a propane
torch wotsit, so I'll be having a hack around with that this weekend. Oh
shit - B&Q on a bank holiday weekend, I'd better pop in on the way home
tonight.

Need a vice as well, not sure the SO will go for "just hold this" in
this case.

 

You could try to weld another socket bolt to the original to give you a
new purchase.

 

Don't do it. You'll heat up the casing just as fast as you heat up the
screws so you'll get no rapid expansion/contraction to free the screws
off. You want an oxy-acetylene set and a small brazing nozzle to get
heat into the screw fast and then when it cools off completely have
another go at shifting it.

I can't do anything to help right now but if it's a long term project
and you can get the bits off the bike I'll do it at some point.

 

Hmm. I think this would be a bad idea on old, fucked, rusted allen
bolts. Champ's suggestion of filing flats is one that could be
considered; or using a suitably sized stud extractor (one that fits over
the stud) providing there's enough head on the bolt on which to get
purchase.

If it was bigger I'd suggest stilsons.

 

The exhaust is fucked, so I can always just remove the pipe leaving me
with much improved access to the bolts.

Work starts tomorrow....

 

I've got a complete original exhaust from the turbo onwards, so I'm
sorted - thanks.

 

Update:

None of the bolts came out :-(

I've removed the turbo and drilled one out completely before my crap
drill bits went blunt. Plan is to replace the bolts with bolts+nuts,
this saves me the job of tapping the threads into the turbo casing, and
there's enough meat on the casing to allow this. I can then prefit the
link pipe and hopefully put it all back together.

Heat, hammering, impact driver, torx driver etc, all were tried and
failed. I managed to get very good purchase on a couple of the bolts but
they weren't moving. Even when drilling them out they were "as one" with
the casing.