Thread: Under Body Sealant

I think this would be a good thing to do. My 2003 Defender had thick black tar type sealant sprayed on underneath everything from the factory. That hardly leaked dust at all from under neath. (It sucked dust in from every where else though.)

Originally Posted by AndyG

IF one was to have the Dealer, or a third party apply under body sealant to a new Defender what are the chances it would block all the water & dust holes under the car.
Not sure if they use a thick tarry substance or a swipe of WD40 equivalent

They're not water & dust holes - they're drain holes.
Fill these & you'll end up swimming in your Defender.

My 2003 Td5 Deafener was the same but absolutely nothing on the Puma. I'm just going to soak the chassis inside and out the rest of the under works with Lanox or something similar.
I did the inside of the doors with it and some leaked out and down the sills....water alone would not shift it so it must be a good rust preventative.
AlanH.

Originally Posted by ATH

My 2003 Td5 Deafener was the same but absolutely nothing on the Puma. I'm just going to soak the chassis inside and out the rest of the under works with Lanox or something similar.
I did the inside of the doors with it and some leaked out and down the sills....water alone would not shift it so it must be a good rust preventative.
AlanH.

I used Inox MX3 inside the door frames, bulkhead and rear cappings. My reasoning here is that it's very liquid and seep very well. It's still seeping out of the body side rivets some 6 months later - so I know it's spreading very well. I used the Lanox on the chassis in the corners etc where it's hard to clean.

On my prior vehicle (MY09) I used Tectyl 506. That's actually much much better than the Lanox. I found the Lanox seemed to dry out a little and wore off in places under neath. The Tectyl was as good as the day I applied it when I sold the MY09 4 years later. In hindsight I should have used this instead of Lanox on my MY13.

The Tectyl 506 was a bit harder to apply, and needs to be thinned a bit, and heated to really spray Ok.

So my recommendation is to use Tectyl 506 underneath, and Inox MX3 injected wherever you can.

For plugging holes, butyl mastic seems to be a popular choice.

BilboB,
Is Tectyl tacky enough to seal small cracks between panels ?

Tectyl sprays on quite thick. It will fill under a mm gap. I used butyl mastic on the bigger gaps.

The best is to paint the tectyl on as it is then nice and thick and stays on for ages.
Bloody tedious and messy.
And some areas still have to be sprayed as the paint brush will not reach all areas.
I sprayed the D4 underneath with it,and it didn't seem to last long,particularly at the rear of the vehicle.I then painted it on and it has lasted ages.