Exploring the Mazda Bongo

In the same way that we have looked at the T4, T5 and T6 – here I will take a look at the common problems associated with running a Mazda Bongo. Along the way I will point out a few low-cost tips and tricks to extend the life of a Bongo.

The Mazda Bongo is a fantastic choice when it comes to the campervan options here in the UK. The Bongo is one of the most popular alternatives to the VW Transporter T4 and T5 generations.

You can frequently find bargain Bongo’s on the second-hand market for extremely low prices (Sub £4k!), Despite having higher specification from factory – Bongo’s suffer greater depreciation than the Transporters and for this reason, they are most certainly worth a look.

Have a quick browse:

Have a quick browse at the current market prices below, you might be amazed. You can pick up Bongos anywhere from £2k upwards. At the dearer end you can get the pop top campervan conversions and the rarer 4×4 models.

At the lower end you can pick up “Tin tops” that are essentially factory specification people carriers with fold down rear seats that form an amazingly comfortable full width bed,

Mazda bongo problems

Despite the stunning value of the Mazda Bongo, there are some common problems associated with this campervan that should be checked either prior to purchasing, or if you already own a Bongo then there is some preventative maintenance that is worthwhile.

Here, we will shed light on some of the Mazda Bongo’s problems to further understand this van. Some of the issues covered will be overheating, mazda bongo elevating roof problems, gearbox hiccups, MOT failure, rust, and electric windows not opening.  

Mazda Bongo overheating problems

One of the most common problems associated with the Bongo is overheating. Typically the diesel variants suffer the most with this issue however this still applies to the petrol engines to a certain extent also.

They have gained an unfortunate reputation for this issue that is widely documented. The overheating can be caused by a few things such a faulty water pumps, slow leaks either in the coolant hoses or small holes in the radiator.

Most frequently however, the overheating occurs when one of the rubber hoses in the coolant network splits, usually due to age. This results in the loss of the coolant (usually quite slowly at first). This in it’s self isn’t the major issue… The big issue comes later.

The Bongo, as standard, does not have adequate low coolant warnings. This short fall frequently leads to engine damage (head gasket and cracked heads) as the driver is unaware of the lost coolant until it is too late.

If your hoses/radiator or water pump has not been changed recently, this can be a great bit of low-cost preventative maintenance to carry out. When you inspect the hoses, give them a squeeze, if they feel hard or appear perished they should be replaced.

Mazda Bongo coolant hose common problem

If your Mazda Bongo has overheated…

Ok, so usually if a vehicle overheats it can deal with it to a certain extent. The Mazda Bongo unfortunately does not cope well at all.

The Mazda Bongo cylinder head is very fragile to overheating. It can be weakened very easily. If it doesn’t crack the first time you overheat, chances are that it is vastly weakened and will not deal with another episode well.

The most frequent damage caused by overheating is a cracked cylinder head (costly), a blown head gasket (not quite so bad). other elements are also weakened and are left prone to failure in the not-too-distant future.

Check all hoses and if there are further over heating problems it is advisable to replace the following items:

  • Head gasket
  • Head bolts
  • Camshaft seals
  • Rocker cover seals
  • Valve stem seals
  • Manifold Gaskets
  • Thermostat
  • Coolant system hoses
  • Water pump
  • Cylinder head (if it has cracked or shows any signs of damage)
  • Check the radiator and replace if required

You can buy complete kits for this (HERE) which usually work out a bit cheaper than buying individual components.

Mazda Bongo Overheating Alarm – Preventative maintenance

A low-cost upgrade installed on the Mazda Bongo gives the user an early warning sign of an impending problem that would cause the engine overheating. This upgrade is referred to as the Mazda Bongo coolant alarm, also termed a low-level coolant alarm.

Bongo coolant alarm upgrade to avoid common problem

This in-line sensor alarm gives the user notification on the cooling level. In case of a problem, an audible and visual alarm will go off, which will signal a user of an impending problem that would likely result in overheating.

In this sense, the Bongo coolant alarm upgrade comes in handy to give the user peace of mind that their cooling system is being monitored. This upgrade is imperative because it further prolongs the life and value of the Mazda Bongo.

Mazda Bongo Head Gasket

The head gasket is an integral part of the engine located between the cylinder head and the engine block. The head gasket’s central role is to seal the cylinders to ensure the achievement of maximum compression.

One of the Mazda Bongo common problems is head gasket failure (normally caused by the overheating mentioned above), depending on how severely it has failed it isn’t always immediately obvious either!

to identify the problem:

  • Check for oil leaks around the engine
  • Check for water in the oil (open up the oil cap – there should be no white residue)
  • Overheating – Leave the engine running for a while and check that the temperature stabilises
  • White smoke from the exhaust even when warm
  • Coolant loss that is not obviously explained
  • Take the cap off the coolant reservoir and check for bubbling. This is a sign of air being pulled in through the head gasket.

Mazda Bongo Head Gasket

Mazda Bongo elevating Roof Problems

Another common problem with the Mazda Bongo is when it comes to elevating the roof. There are many reports of users complaining about the inability to open them. This problem is often linked to failed motors or wiring issues.

The roof will not open if there is an incomplete electrical circuit, and so checking the wiring during the troubleshooting process is the first step but unfortunately can be time consuming.

mazda bongo elevating roof problems

A word of caution here also – The roof is best not opened with the Bongo parked on a sloping angle as it can put undue weight onto one side of the roof structs when elevated.

The struts can buckle under pressure on the one side and leave you stranded with a roof that you cannot lower back into position to drive.

Mazda Bongo Gearbox Problems

The Mazda Bongo has also been noted to suffer from gearbox problems, and in most cases, the gearbox requires reconditioning to get the van back to its proper functioning state.

The downside is that the refurbishing of the gearbox may cost anything from £1500 and over.

Mazda Bongo not Changing Gear

On the Bongos with the automatic gear box, another common sign for an impending issue (that is usually caused by a solenoid problem) is when the hold light flashes and the Bongo will not engage into top gear.

Unfortunately Bongos are getting on in age and electrical issues start to become apparent in the higher mileage examples.

This issue only becomes obvious when on a 50+ MPH road so it is important to test drive up to this speed to ensure you can adequately check for this

When troubleshooting the cause of the transmission fault start by looking at transmission fluid, gears, filters, and bell housing.

Mazda Bongo Electric Windows not working

Gearbox aside, another common issue with the Mazda Bongo is the electrical windows not working.

This issue is often linked to either the window switches breaking, a loose fuse in the fuse box (or a blown fuse) or occasionally it is traced to a loose connection in the loom where the wiring goes from the “A pillar” to the driver door.

Mazda Bongo Rust Issues

Similar to the VW T4, a pervasive problem encountered by the Mazda Bongo users is the rust problem. Which can cost in excess of £2000 to repair under extreme circumstances.

The main reason for this, particularly for the UK buyers, is that these campervans were not built for the UK’s wet climate. Worse still, the salt that is applied to snow / ice during cold winters accelerates the corrosion.

Mazda bongo rusted arches problem

Some well looked after versions are undersealed at the point of import, those that are not undersealed however suffer very badly over time which will result in ultimate MOT failure.

Rust is one of the most common reasons that Mazda Bongos reach the end of their useful economical life due to the cost of repairing badly rusted arches, sills and vital chassis mounts

Proper maintenance and servicing will come in handy to keep rust problems under check.

Mazda Bongo Sills & other rusty areas

The Mazda Bongo sills are some of the van’s parts mostly affected by rust. In severe cases, the rusting magnitude warrants a replacement of the inner sills.

Key areas to check for Bongo rust are starting from the rear cross member, rear arches (inside and out). If there are arch covers fitted it is worth removing them and treating any rust that maybe developing underneath them. They can be moisture traps.

Check the front cross member (the radiator attaches to it) including mounting points. The other area prone to rusting is around the rear heater matrix.

These are the key areas that are expensive repairs however rust can develop anywhere on the underside of the Bongo so if you can get it up on ramps periodically it is worth checking and treating rust before it gets severe.

Mazda Bongo MOT Failure problems

The Ministry of Transport (MOT) test is a test performed annually to check roadworthiness, safety, and exhaust emission of most vehicles three years and older. The test is done per the UK’s requirements.

Most MOT failures on the Mazda Bongo relate to

  1. Rusted mounts/sills or arches
  2. Electrical faults
  3. Emissions
  4. Dirt ingress in the dust cover
  5. Rust underneath the vehicle, or even on the suspension arms

Before buying a Bongo it is worth looking at prior years MOT advisories to ensure that all maintenance and repairs have been carried out.

Be especially cautious of any Bongos that have rust mentioned as advisories on prior years as the repair can cost more than the vehicles value.

Mazda Bongo common problems conclusion

Like with any vehicle, if the appropriate maintenance is not applied, there is a strong likelihood of problems developing.

The same can be said for the Mazda Bongo. Whilst a well maintained Bongo will fetch a considerably higher asking price, it can be worth while to pay that bit extra to avoid running into problems and expensive repairs.

It is worth noting that with the appropriate servicing, users can catch problems beforehand, thus prolonging the value and usefulness of this campervan.

So should you buy one?

If you find one in nice condition – Go for it! The Bongo’s offer great value for money and the majority are already up to a nice specification for family camping trips.

If you get one, keep an eye on the coolant level, and invest a few £ to get a coolant level alarm installed.

It is well worth slapping on a few layers of decent underseal as well, even if it has been done in previous years. You can read my undersealing guide HERE

You may also like