Dynamat "underneath" ? (tunnel, footwells, transaxle, lid)

[unplannedbbq]

I've read a bunch on noise reduction threads, and I've got my strategy for inside the van underway, thanks to:
https://www.thesamba.com/vw/forum/viewtopic.php?t=606406
https://www.thesamba.com/vw/forum/viewtopic.php?t=532900
https://www.thesamba.com/vw/forum/viewtopic.php?t=566289
https://www.thesamba.com/vw/forum/viewtopic.php?t=573636
https://www.thesamba.com/vw/forum/viewtopic.php?p=6901474

So, the bottom of my van is completely stripped. I'm planning on using self-adhesive sound/heat blocking in the tunnel behind the radiator.

I've cleaned up surface rust on the bottom of the footwells (e.g. - lots of scale above the wiper fluid reservoir, corrosion inside accelerator cover) I've also cleaned up the over-transaxle area & "firewall" - I can't find any more rust on my van.

Would the exterior footwells, engine cover, interior d-pillar (snorkel), over-tranny and firewall areas benefit from dynamat or something similar?

Any concerns re: exposure to elements? Should I be afraid of adhesive breaking down over time & water getting between body panels and dynamat?

Thanks.
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'86 x-1wd, now w/ 2wd! Wolfsburg Weekender

"However not an ideal swap unless it was all you had and you needed to escape some distopian 3rd world country." - Mongoswede

[Merian]

there are materials made for that use, but not Dynamat

not clear it will help with engine noise as it is far from your ears

a liner can help with impact noise from pebbles etc. thrown up by the tires

I'd bet wind noise is your biggest issue once you have treated the doors, sides, and cowl
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[bluebus86]

regarding water, you wont get 100% adhesion with all the contours to cover and seams. if you plan on getting the van wet, use a quality epoxy primer, chaulk with a quality urathane water proof seam sealer, paint a second coat, and optional bed liner.

even the factory matts arent perfect, however they melted in with heat, I am not sure the self adhesive aftermarket matts are as good

for best results, keep the van dry, lay some carpet down to catch spills, you dry it out, throw carpets, scrap house carpets can be laid down as top matts when you are using van in rain, snkw and expect water to get tracked in, this keeps your wall to wall van carpet dry and clean, and that inturn keeps the dynamatts dry,


so unless you plan to hose out your van, or leave the windows down in the rain, go ahead and use the matts, and take steps with carpets and such to catch any water that gets tracked in. lots of layers of carpets of convienent size to allow easy removal for cleaning and drying is a great way to absorb up tracked in water.


good luck


ps in a camper with the vents cut in the side of the body for the sink, heater , fridge and such, do not apply matts directly under the holes in the body. these vent holes do eventualy leak, and a matt will trap water between it and the steel, the same is true for heat insulation like foam or fiber glass, dont put it under potential leaks where it will conceal the dampness and rust, this may trap hidden moisture long after the exterior dries out.
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[0cean]

FYI: One thing I have found out is that spray able sound dampener is very flammable. To flammable for being the top coat of the under carriage.

I was thinking of Epoxy Primer/Sound Dampener(Lizard skin)/ and topped with Monster liner bed liner. My concern is to much products and falling off over time. Anyone ever do this? Would it work in the long run?
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I'm not a mechanic, I just play one on the internet

Cluster Rebuild:
http://www.thesamba.com/vw/forum/viewtopic.php?t=569920&highlight=

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http://www.thesamba.com/vw/forum/viewtopic.php?t=613669
(Number of Different Donor VW Vans Body Parts Used: 12)
(Number of completely different vehicles parts used: 3)

[Terry Kay]

I sprayed the entire bottom side of my 87 sixteen years ago with Uprol Raptor, it's still all there, looking good.

I hot water pressure washed the entire bottom, @ 3500 psi, let it dry, blew out the crevasses with a pencil blow gun, and applied the urethane bed liner with the appropriate bed liner gun.

Nothing to it, cut out a bunch of road noise.
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T.K.

[bluebus86]

two subjects here, underside floor and inside floor. glue on matts are not the best thing for underside, it gets road spray, very wet, high potential of trapped moisture. underside is best served with under coat sprays, thick paints, corrosion protection oils, wax, ect....

inside matts are ok if you keep the interior floors dry, keep them dry with layered throw rug matts when water is expected.

good luck
_________________
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

[unplannedbbq]

Thanks all (especially TK for the long-term report on raptor.)

I did the "gowesty" exterior raptor treatment a couple years ago and it's held up great. Panel seams cleaned and re-sealed before primer. Also bedlined interior floor the whole way through. I'll spray underside of foot wells, all 4 wheel wells, and above tranny w/ more raptor.

I will use sound/heat blocking self-adhesive in the tunnel based on this feedback & other threads, and I'll add more dynamat to the rest of those spaces on the inside of the van to cut resonance & add another layer under carpet/pad/barrier up front.

I have a pop-top weekender, w/ full bed & bench, so engine noise is not a big issue.

Think I'll still put some dynamat behind my snorkel and on driver's side - I've taken the westy paneling off and have bare metal on the inside of the d-pillar.


Thanks again.
_________________
'86 x-1wd, now w/ 2wd! Wolfsburg Weekender

"However not an ideal swap unless it was all you had and you needed to escape some distopian 3rd world country." - Mongoswede

[Skullbag]

unplannedbbq, what did you use to bedliner the interior floor pan with? Thinking about something similar myself.