Stripping Out - Holes in Metal Floor - Whats this?

[Cotton Daisy]

Evenings Folks.

I now have a panel van and have stripped out the ply lining but I need some advice please. The ply on the floor was screwed down and there are 8 - 10 holes through the metal floor. I've gone round them with a kebab stick to check the depth. For most I'm hitting something and for at least 2 I can see daylight. I understand I should apply red oxide metal primer to the holes. Question is - where? Internally and/or under the van? Is there any further steps I need to do before fitting the underfloor insulation?

I've attached a photo of the rear nearside panel which has a sheet of something stuck to it. Any ideas what it is? Am I ok to apply sound deadening over it?

Thanks in advance

 

[B.different]

That's sound deadening from factory. As for the holes i would run a drill bit thru the holes to clean the metal, then treat with rust treatment and hammerite. After that put sealer on both sides.

 

[Paynewright]

As above - I’d probably stick a small steel pop rivet in the hole with a bit of PU adhesive to seal it!

 

[T6Ollie]

As above - I’d probably stick a small steel pop rivet in the hole with a bit of PU adhesive to seal it!

Steel specifically? Would a regular pop rivet be steel anyway?

 

[Paynewright]

Most are ally with a steel pin up the middle. These would be OK too especially with some sealant on them.

I’ve fitted steel pop rivets on something else and you need the grip of a tyre fitter to install them. One or two are OK - I had about a hundred so borrowed a pneumatic air riveter. Very satisfying to use.

 

[T6Ollie]

Ok thanks. I wasn’t sure if ally into a steel hole in the van might be a problem. I will have some screw holes to fix in the floor soon

 

[manfrotto]

I would be tempted to just get some rubber bungs for the holes (if you can get some small enough)

 

[Dannyb6467]

Id probably go straight in with a blob of SikaFlex forced into the holes. Rust proofs, water proof/seals all in one hit. Then a bit of sound deadening on top.

 

[ben5560]

Mine was the same, the garage I bought it off couldn't bothered to reuse the panel clips so they just screwed into the metal with wood screws

Sounds like the best bet for me as well would be to drill the holes to ensure they are neat (the wood screws haven't left them flat) and then use hammerite, then rivets

 

[Paynewright]

I suggested steel rivets due to the dissimilar metals thing but as a non structural / non critical hole filler with some wax / sealant on it, ally rivets will be fine.

I’ve just had a nightmare job changing an ally coolant pipe that had pinholed where it passed through a steel clip. Road salt played a part. This was on a 996 Porsche