Technical Alternative sump options

[Pugglt Auld Jock]

Thanks Jim. Praise indeed from you, I'll have to drop in and see if my local branch has it. Does it actually say "Truck Bed Liner" on the tin? I can't see it listed on their website unless this is it? https://www.halfords.com/motoring/p...pray-paint-rubberised-black-300ml-204557.html

 

[jimboy]

Thanks Jim. Praise indeed from you, I'll have to drop in and see if my local branch has it. Does it actually say "Truck Bed Liner" on the tin? I can't see it listed on their website unless this is it? https://www.halfords.com/motoring/p...pray-paint-rubberised-black-300ml-204557.html

Hi Jock, yes it says exactly that on the tin. Under the paint department.

 

[vexorg]

Will need to have a look for this stuff too, having looked at the sump closely, it's surprisingly rusty on the surface.

 

[jrkitching]

Hammerite is better than nothing

Actually, for chassis/underbody/sump protection, it's worse than useless. The paint invariably develops cracks, salt & water then collects between the paint and the metal, so that it never properly dries out and just keeps rusting away under the paint. Worse, a casual glance may look fine, unitl it gets serious, then the paint and metal both start falling away in chunks.

There isn't really any paint that works well in this situation; it's much better to use a wax based self healing coating; waxoyl will do, but there are better alternatives, such as the dinitrol range of products.

For the sump, you can do a whole lot worse than wiping a rag soaked in oil over it at every oil change. Being paranoid, I use clean oil for this, but the old sump oil will be a lot better than nothing. If you do this from when the car is new, the sump will last the life of the car.

If you want an insight in what works well for protecting mild steel in a hot, wet environment, take a look at the underparts of a steam engine. You'll find everything that's not oily is covered in thick chassis protection grease.

 

[Pugglt Auld Jock]

Actually, for chassis/underbody/sump protection, it's worse than useless. The paint invariably develops cracks, salt & water then collects between the paint and the metal, so that it never properly dries out and just keeps rusting away under the paint. Worse, a casual glance may look fine, unitl it gets serious, then the paint and metal both start falling away in chunks.

Hmm, so basically this stuff is like the old bituminous underseals? I've done battle many times with the problems that stuff causes and have the scars on my neck where it melted off and dripped down whilst welding! Definitely don't want to cause myself to revisit that scenario thank you!

 

[jimboy]

My days are also numbered under my cars. Over the years I’ve had success with sumps I’ve had to sort out one way or another. Both cars in my ownership at the moment have alloy sumps, keeping them clean is all that’s needed.

 

[vexorg]

How about powdercoating to outside?

 

[jrkitching]

How about powdercoating to outside?

I doubt it would last more than a few weeks. Manufacturers powdercoat parts like this, because (in production), it's cheap and doesn't waste much paint.

If you want an example of how well it works as an underbody protection, just look at how quickly the factory finish peels off the twist beam.

If you absolutely must paint stuff like this, chemical surface preparation of the bare metal followed by etch primer and a 2K finish is the way to go. If I were refurbishing a classic showcar, that's undoubtedly what I'd use. But smearing a handful of chassis protection grease over it is way easier and cheaper.

 

[irc]

Chassis grease is definitely good, but messy.
I think a good load bed liner product would work on chassis items like the Panda rear beam.
I used POR-15 bed liner on the running boards of my Discovery. Hgh abrasion/damage/bending area (including some "Hail Mary" recovery adventures and lots of careless pressure washing) and it was still good after 4 years when I sold it.
Fairly dull finish, but comes clean easily.
I did use the proper POR-15 Metal Prep before painting.
If it flexes but stays in place with that much abuse then it may well be good enough for rear beam, if you really want to paint.