best underbody sealant to use

[david106]

I'm in the process of trying to get my touring back on the road been at it with the wire brush under the arches etc and cleaned the petrol filler pipes up etc but need something to protect the metal from rust.
Whats the best stuff to use either hand painting or rattle can

[mcbonio]

I too also would like info on this..

[Jozi]

You need to make sure all the rust is gone otherwise it will come back!

I'm going to be primering any bare metal before spraying on a underbody seal, have a dinitrol product for this but there are also other brands that do the same. On top of this I might apply a underbody wax from bilthamber, dynax uc I think it's called.

I'm not one for using waxoil although I suspect many will recommend it.

[Dan320is]

Having used Dinitrol and waxoil products I would definately go for the dinitrol. It has a much better finish and lasts.

[scjimbo]

If your after an actual underseal i use dinitrol. However before applying this I use a product called Ixel (From Renault believe it or not) It was recommended by me by an old school body shop guy local to me. Its actually a cavity rust protectant used in places like inside the arches between the plastic liner and the wings themselves.

Its great to use under the the underseal because it soaks up into gaps and cracks in the car panels inhibiting the rust that may be forming in there too.

I also found that with the Dinitrol you can over paint it with hammerite for that extra shine.

[Jos]

Vactan to kill rust then Jotamastic 87 - 2 part epoxy used for marine applications, available in 4 colours and they do a GRP reinforced version too.

Takes weeks to cure mind you..

I follow the think rust: think marine method

[Grrrmachine]

I welded up my floor six months ago, but got under it this weekend to see tiny orange bubbles poking through the stonechip. And that was after using Dinitrol, brushable seam sealer and a coating of stone chip

So I need a more rigorous rust killer too.

[SGP]

Hi, This is my method;
1. removing all the rust with a range of wire wheels flap discs etc.
2. Cleaning the area with brake cleaner and compressed air.
3. U-pol 'acid 8'etch priming the steel. (allow to dry for a few days)
4. U-pol brushable seam sealer, (again plenty of dying time)
5. (Bardahl)undercoating. (Dries very slightly tacky)
6. satin black enamel (tank and pipe)
7.(Rusco CW) wich dries hard (over the enameled steel parts for waterproofing.
Allowing each product to dry over a few days is important to avoid any reactions.
I had to drop everything from the rear end including the tank to get at it properly.
The advantage of the rattle cans is better precision and a huge range of different products, they can be expensive though so if you want it to last, good surface preparation is (very boringly) essential.
Fingers crossed this works, but I'll be keeping a close eye on it.