Clean heat exchanger. Clean accordion tube. Filthy heat channel?

[ultralite]

So I have my ‘67 in a thousand pieces for a restoration. Pics coming soon.

I was taking a look at the heating system to see if I need to adjust flaps while I have easy access. I took off the accordion tube and was about to push thru some compressed air to check air flow.

I reached into the metal heat channel attached to the body. Right at the rear fender. It’s filthy.

I then felt around the heat exchanger (inside), clean. Felt around the inside of the accordion tube, also clean on both ends.

The inside of the heater channel was black like soot, not brown like rust. They otherwise look really good.

Makes me wonder how far in the “sootiness” goes?
_________________
Godspeed

'76 Beetle (sold)
'69 Beetle (sold)
'72 BMW 2002 (RIP)
'69 Westy
'02 BMW wagon AWD w/stick shift(sold)
'67 Beetle (sold)

[Digger89L]

That won't be soot inside the heater channels ...it will be oil residue. At some point in your car's life it had an oil leak in the dog house (likely a bad oil cooler, or oil cooler seal) that was leaking oil that got hot / or burned off and was forced thru the heat system ...the PO had the leak fixed, changed the heater tubes, and left the residue inside the heater channels (do you smell oil in the car when hot air is coming in?) Not sure how that 'soot' could ever be flushed out, but it could possibly be done by forcing some kind of cleaner back thru the heater channel from the front floor outlets. Just an educated guess ...
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"If you can't fix it with pop rivets, crazy glue and duct tape, or hold it together with zip ties, velcro or magnets, it REALLY is broken."

[bluebus86]

Use care handling asbestos bits in the heater system. some Bugs had asbestos surfaces on the heater hose, the one that connects to the chassis duct.

Bug On!
_________________
Help Prevent VW Engine Fires, see this link.....Engine safety wire information

Stop introducing dirt into your oil when adjusting valves ... https://www.thesamba.com/vw/forum/viewtopic.php?t=683022

[KTPhil]

On a '67 with the "clean air" heat exchangers, an oil cooler seal leak will not normally introduce fumes into the heater. A burst cooler might, but that's very rare.

Is the black junk mold maybe, from a water leak into the heater channel, perhaps as far away as the windshield?

Is your muffler leaky at the joint with the HEs, such that the soot is blown into them past the clamped donut seals? Type 3s were known for this and had a secondary seal around the sheet metal jacket where the exhaust tube exited for this reason.
Red arrow points to where a leaky muffler donut seal can inject exhaust soot into the heater air stream:

How does the rest of the heater channel look? Check at the front footwell slider, and also at the rear floor outlet.

You may have to do a Mary Poppins chimney sweep imitation to brush that crap off of the heater channel walls, maybe with the car tilted rear-low to ensure it drains back.

[ultralite]

Asbestos?! Interesting, I’ve looked up the other threads on the asbestos topic. I had no idea.

So my asbestos rings on the tube appear to be intact.

It wasn’t clear from the other threads if the inside of the heater tubes contained it as well. Does anybody know?

I have not had a chance to get back to the sootiness yet. But I did want to thank folks for the ideas and suggestions before too much time passed. I have a chimney sweep type brush that appears to fit perfectly.
_________________
Godspeed

'76 Beetle (sold)
'69 Beetle (sold)
'72 BMW 2002 (RIP)
'69 Westy
'02 BMW wagon AWD w/stick shift(sold)
'67 Beetle (sold)

[KTPhil]

I only know of three possible asbestos seals:
1) On a Type 1/early 2 engine, those white seals around the heat riser, embedded in the tin (lower left):

2) On a Type 3, on the rear of the large heat exchangers, the extra seal at the meeting of the sheet metal jacket and the exhaust pipe (just ahead of the main clamp/donut seal). There should be a seal and clamp at the red arrow:

3) Those sealing "rings" at each connection of the large heater flex hoses under the car, usually covered by a sheet metal ring, seen here:

The inside of the accordion tubes is usually a batting type material

[bluebus86]

I sprayed hitemp BBQ paint on the asbestos heater seals, this seams to have glued the fibers inplace. Then followed up with metal heater tape.

heck I have a cement asbestos flue for my stove vent exposed in my garage, asbestos asphalt tiles under my home carpets, and asbestos tape on my furnace ducts (since sealed with paint and metal tape)

I used to camp, 4 wheel, and plink in an area that is full of natural asbestos, that area was closed some years ago, Hollister Hills.

I used to blow out dusty brake drums with compressed air, that now worries me a bit

Bug On!
_________________
Help Prevent VW Engine Fires, see this link.....Engine safety wire information

Stop introducing dirt into your oil when adjusting valves ... https://www.thesamba.com/vw/forum/viewtopic.php?t=683022

[KTPhil]

The brake work is the only one that should worry you. Solid asbestos in not harmful. It's the fine fibers that become airborne that do the damage.

In your heater system, containing it with paint or other binders is a good step but I'd find a substitute. All the vibration and airflow in those parts would concern me.

[Digger89L]

[Eric&Barb]

[viiking]

[ultralite]

Thanks for all the replies and information. I was messing around with the Bug today. I think in the end I was seeing what was really just some grime that collects on old things.

I took some “Super Clean” and an old T-shirt. It wasn’t that bad. Here’s a photo of the 2 different heat channels.

Here is a shot looking back into each heat exchange. What is the white object toward the bottom? (Or once white, looks kind of rusty/dirty)

_________________
Godspeed

'76 Beetle (sold)
'69 Beetle (sold)
'72 BMW 2002 (RIP)
'69 Westy
'02 BMW wagon AWD w/stick shift(sold)
'67 Beetle (sold)

[viiking]

Cast iron baffles on the heat exchanger surrounding the exhaust tube.

[Eric&Barb]