Mazda Bongo Undersealing in Plymouth, Devon 

I've undersealed Bongos in Plymouth, Devon, for over 17 years. Nothing can totally prevent untreated steel from rusting. But undersealing a Bongo can help to prevent rust. I've invested in new underseal equipment, to help to keep your Bongo rust-free.


Why does a steel vehicle rust?

Rust is formed when steel and oxygen react with water or mositure in the air. Rust on the surface, is flaky and permeable to moisture. Beneath that rust, more moisture and oxygen make contact with the steel, which continues to corrode. Given sufficient time, your Bongo will completely rust away. Waxoyl (wax oil) underseal provides a barrier, which protects the steel from air and moisture.


How long does it last?

The re-application inteval is generally every 3-5 years. This varies, depending on weather conditions and vehicle use.

How do I underseal a Mazda Bongo? 

First, I clean the underside to see the rust clearly. I use high pressure sprays to remove dirt. This also removes some flaking rust. I may also need to wire-brush the rust; its a labour-intensive process. Your Bongo is then dried. 


Some Bongos require more preparation than others. This can include application of rust converter or removing and welding badly corroded areas.


When all the preparation is complete, I protect areas (such as breather vents) that should not be sprayed.

If the waxoyl treatment includes injection into panels, I remove grommets, stoppers, lights etc, to gain the access I need.

Waxoyl rust prevention is pressure-sprayed and leaves a clear or black, waxy, moisture resistant coating.

Inside the panels, it's applied as a mist, so it penetrates further.


How long does it take?

Its best if your Bongo is left with me for one full working day, then overnight, to give the waxoyl time to harden fully.

But as many customers can't leave them overnight, I'm happy to start work early, so you can collect the same day.  

If a lot of preparation or welding is needed, it may take 2 or 3 days. I can let you know when we discuss undersealing of your Bongo.


What does it cost?

My treatment options can be tailored to suit your budget.

I underseal the underbody, wheel arches and under bonnet, or the under body, wheel arches, under bonnet and injection spray into panels and cavities. 

I don't cut corners and I take time to do a proper job, with the experience gained from 17+ years of undersealing Bongos.

This costs  from £250 plus vat.


Contact me to book your Mazda Bongo or Ford Freda underseal at my garage in Plymouth, Devon


If you want to underseal a Bongo yourself, I found a video that shows you the general idea: WAXOYL APPLICATION GUIDE I advise you to wear protective clothing and a mask designed for this work, so you don't inhale the waxy mist.


Do not powerwash, hot wash or jet-wash waxoyl, after it has been applied. 

Welding a Mazda Bongo or Freda in Plymouth, Devon

Rust and corrosion on a Mazda Bongo

Here are a few photos of rust on an untreated Mazda Bongo. As you can see, it had never been undersealed.

It came in for an MOT and failed on 'excessive corrosion' in several places.

It took a me a couple of days to remove the rusted parts and then weld in replacement panels and repair patches. Once it was restored to good condition, I undersealed it to help to keep it that way!

Needless to say, the Bongo then passed its MOT.

Mazda Bongo sill Corroded Bongo sill
Mazda Bongo rust repair Rusted Mazda Bongo
Mazda Bongo underseal Bongo corrosion
Mazda Bongo rust repair Rusted Bongo underbody
Mazda Bongo undersealing Corroded Bongo underbody
Mazda Bongo crossmember New Mazda Bongo crossmember

Bongo front crossmember corrosion 

If you've been advised that your Bongo front crossmember has rusted and needs to be replaced, this is what it could look like.

It's a structural piece of steel, that fits across the Bongo, in front of the radiator. It's welded in place and is vital to the strength of the Bongo. It must be strong enough to handle all the load applied to it.

If a crossmember is rusted, it's sensible to also check the rest of the underbody, to ensure its structurally solid.

I've removed and replaced hundreds of Bongo crossmembers! I always underseal the new one, to protect it.  

Allans Vehicle Services,

Wixenford Depot, Plymstock, Plymouth, Devon, PL9 8AA.

VAT no: 909 7647 80



Tel: 01752 403400

Mob: 07471 002034

Text: 07471 002034


I work on my own. If I can't answer right away, please leave a message & your number. I'll call you back.


Email: hello@


Open Mon - Fri 8am til late.



Allans Vehicle Services

Wixenford Depot

Colesdown Hill





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