[Shop-talk] Ancient furnace with cracked manifold

Mon Nov 8 11:05:12 MST 2021

As someone that lives in a 'turn of 2 centuries' house (built in the 
1700s), I can tell you they just need to bite the bullet and replace the 
unit.

No matter what the cost, house fire, and/or poison gases are NOTHING to 
gamble with.  I'm a guy that will hang off a ladder with a running 
chainsaw, and I wouldn't take a chance with either of these.

Don't forget, a modern unit will be FAR more efficient and could pay for 
itself in short time.  But replacing one or both loved ones is not an 
option.

There may also be tax credits or incentive programs to offset the costs of 
the upgrades.  Have them research around (but hurry.)  Their oil/gas 
provider, local tax office, internet searches.  They may be surprised at 
the availability of assistance for the upgrade.

As for repairing it, to properly weld cast iron, you need to slowly 
preheat and cool down a piece.  This means it would NEED to be removed so 
it can be placed in an oven.  Then if it wasn't really flat, it could 
crack on reinstallation.

Frankly, before I tried to weld it, I would remove it and try to recast a 
new piece.  Watch some videos on do it yourself cast iron.  Not outside of 
the realm of a DIYer.  Very little specialize equipment required.  Maybe 
you can find someone local to do it.  That way you just 'glue' the pieces 
together to make a mold of it and recast it.  This isn't a high 
performance part, so it should be possible.  A little machining afterwards 
to the mating surfaces and you are good to go.

But I would only do that if replacement was completely unavailable until 6 
or more months.

Moose

From:   Jim Stone <1789alpine at gmail.com>
To:     Shop Talk <shop-talk at Autox.Team.Net>
Date:   11/08/2021 10:54 AM
Subject:        [Shop-talk] Ancient furnace with cracked manifold
Sent by:        "Shop-talk" <shop-talk-bounces at autox.team.net>

My daughter and her boyfriend have bought a turn of the century house with 
an ancient coal-fired furnace that was long ago converted to natural gas. 
It works fine and they’d like to put off replacing it for as long as 
possible while they invest their money in other parts of the house. 
However, the furnace has a cast iron exhaust manifold that is cracked 
pretty badly and it scares the hell out of me.  Following are some 
screenshots from a video she sent me, starting with the overall exhaust.

You can see the top of the manifold in the lower right.  Here is a side 
view:

The orange goop was applied by a furnace tech they hired, who said he 
really shouldn’t have touched it at all but did what he could.l. However, 
here is a shot just below the goop:

And, a shot from the other side:

As you can see - assuming the photos come through - the manifold is 
totally shot, although it feels solid and doesn’t appear to be in danger 
of falling off.  In theory, it could be removed and taken someplace that 
does cast iron welding, but I suspect that would be a royal pain and not 
guaranteed to succeed.  She has a CO2 detector in the basement, but I will 
be visiting her next week and want to try to do more.  “More” might be 
trying to convince them to bite the bullet and replace the system 
immediately, but I have also thought about treating it like an automotive 
exhaust system and trying to patch it to get them by for a season or two. 
What are the group's thoughts on something like JB Weld High Heat putty (
https://www.amazon.com/J-B-Weld-8297-HighHeat-Degree/dp/B007PP26RI/ref=pd_bxgy_2/138-6104268-8394138?pd_rd_w=nQ3PU&pf_rd_p=c64372fa-c41c-422e-990d-9e034f73989b&pf_rd_r=2F076DNFFJBZ1G9PK3TY&pd_rd_r=623d1e00-f712-4380-897c-474fe9ee6337&pd_rd_wg=1YSqH&pd_rd_i=B007PP26RI&psc=1
) and/or their high heat wrap (
https://www.amazon.com/dp/B00N582CBY/ref=emc_b_5_t)?

Thanks,
Jim (and Sara)

[attachment "Screen Shot 2021-11-08 at 10.19.11 AM.png" deleted by Eric 
Petrevich/Megageek] [attachment "Screen Shot 2021-11-08 at 10.12.34 
AM.png" deleted by Eric Petrevich/Megageek] [attachment "Screen Shot 
2021-11-08 at 10.13.09 AM.png" deleted by Eric Petrevich/Megageek] 
[attachment "Screen Shot 2021-11-08 at 10.27.00 AM.png" deleted by Eric 
Petrevich/Megageek] _______________________________________________

Shop-talk at autox.team.net
Donate: http://www.team.net/donate.html
Suggested annual donation  $12.96
Archive: http://www.team.net/pipermail/shop-talk 
http://autox.team.net/archive

Unsubscribe/Manage: 
http://autox.team.net/mailman/options/shop-talk/eric@megageek.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://autox.team.net/pipermail/shop-talk/attachments/20211108/09cf8051/attachment.htm>