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Points gap and plug gap for a 1995 Mazda B2600 4x4 double cab (rough running, loss of power, backfiring)

Good afternoon All

Does anyone know the correct distributor points gap and spark plug gap for a 1995 Mazda B2600 4x4 double cab (petrol motor without fuel injection)?

I’ve had four breakdowns in the last year, the symptoms are rough running, loss of power, backfiring, and eventually no spark. I’ve spent thousands on repairs by a mechanic (and towing fees) but the problem keeps coming back. The car runs normally for a while (usually less than 100 km) then develops the same symptoms.

The mechanic has changed the points and condenser (multiple times) and then the ignition coil (not the ballast resistor). On the advice of an electrician, I’ve replaced the plugs, points, condenser, rotor, and distributor cap. The electrician said the ballast resistor is fine. The motor’s running but still rough. The Mazda B-series owner’s handbook that came with the vehicle when I bought it (2nd hand) has figures for the points gap and plug gap for all models EXCEPT the B2600.

Thank-you.

Have you checked on the support above the radiator or near that vicinity for a little placard? Most vehicles have that information available near the engine.
CSA
:palm_tree: :sunglasses::palm_tree:

If you were billed for points and condenser you need to get a refund and find a new mechanic.

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Points and condenser on a 1995 Mazda? I don’t think so. Points haven’t been found on cars since the early 70’s. Unless someone has removed the electronic ignition and fuel Injection from your truck there is something amiss in your description of the problem.

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Someone has been doing a lot of wild axx guessing. Cap, rotor, and so on will not cause this kind of problem. Maybe the electrical part of the ignition switch is failing OR the ignition coil which I do not see mentioned.

I’m not aware of a 95 having contact points. While I wasn’t a full time Mazda guy, I did have my hands on a few of them at a multi-line dealer where I worked in the mid-late 80s. Those were electronic ignition.

That being said, some models of VW continued to use contact points until the mid 80s. Go figure.

And Toyota continued to use points on their engines into the 80s but the points triggered the solid state igniter as a crank angle sensor. The point set was virtually a lifetime part.

Where are you? They didn’t sell a B2600 in the US that year. Are you sure it’s a 1995?

Double cab compact trucks were sold in South America, Africa and the Midle East.

1995 double cab, distributor points, ‘‘petrol,’’ carb, kilometers…

I’d guess it’s not a U.S. model.
CSA
:palm_tree: :sunglasses: :palm_tree:

The coil should not be difficult to check along with the power source for the oil. Either one would cause lack of a spark. A test light at + side of the coil should show whether power is provided or not. A spark test or sticking a pinkie into the coil tower terminal could reveal whether or not the coil is powering up or not. A minor shock of course…

Miles? You have checked timing marks for chain stretch? Compression?

2600? I wonder if this was a Mitsubishi Mighty Max sold in other markets under the Mazda name. Rock auto lidts that truck but has no ignition parts for it.

South Africa. I bought it second hand but the registration certificate (required for all South African vehicles) states that the first date of licencing was February 1995.

@common_sense_answer. There’s a plaque on the back on the engine compartment. I seem to remember only serial numbers but I’ll check.

@asemaster. Here’s a photo of inside the distributor. I bought the vehicle second-hand so I can’t be certain but I think this is probably as-sold in South Africa at the time.

@ok4450…wild axx guessing…” is about right. I changed the cap & rotor on the weekend, the problem hasn’t gone away. The coil was changed last year (by the mechanic), ditto. There’s a growing list of parts changed with no solution (meaning that all the parts replaced so far were probably fine). I’ll add the ignition switch to the list of things to check-out (thanks for the idea). The electrician says the coil is fine (he used an electrical tester of some kind, not a pinkie).

@Cavell. Compression is OK. I was advised to get the gaps to their correct values before checking the timing.

@oldtimer_11. Apparently the 2600 is a Mitsubishi motor, although the Mitsubishi Mighty Max was sold in South Africa as the Mitsubishi Colt (Wikipedia).

Qualify that with - “In the United States”. Vehicles in South America had points in some of their vehicles built after 2000.

Well I sure got caught on this one.

But when no specifications can be found I recall that ~40* dwell is appropriate for most 4 cylinder engines.

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It’s pretty amazing to see a set of points again. I suggest you try gapping them at around 16 thousandths, or .406 mm. I think that will get you at least pretty close to what they should be. Finding a problem with the ignition circuit should be easy as pie. Follow the power to supply line to the points.

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It’s unusual for a 95 model to not have fuel injection here in the USA. Likewise to use points. But since that’s what you’ve got and you’ve pretty much ruled out the ignition system , my guess is the carburetor is plugged up and needs to be rebuilt or replaced. If the engine air filter or fuel filter routine maintenance got deferred prior to these symptoms, this is even more likely.

Carburetors were still widely used in the USA until the mid-80s. Those early 80’s carbs – probably the design you have – were electronically controlled to meet emissions rules and tended to be problematic and quite difficult to diagnose. The problem is often the electronic control mechanisms.

We always used sixteen thousandths as a starting point when we had no specs. Btw, that is the thickness of a business card which can be used in a pinch.

I used a cover from the paper matchbook’s if you remember them. Also the stricker part made an emergency file.