Problems with Misfiring

Andrew_shaw

I am very new to mechanics and i got a 1987 B2000 to learn on but i cant figure out the problem, i changed all the spark plugs, distributor cap, rotar, did a Weber swap and tried timing but for some reason my engine can’t go any past the white line or it will just run horribly, and i cant seem to think of any reason why the engine could be misfiring as bad as it is. It only does it when getting into higher RPMs and I’m at a loss. Help would be greatly appreciated

MazdaMitch

Andrew_shaw you should have done one thing at a time.

What is this white line you're talking about?

Andrew_shaw

MazdaMitch the white notch on the harmonic balancer

Cusser

Andrew - sounds like you have little experience. I'd check the firing order of the spark plug wires; the firing order is 1-3-4-2 with 1 being the cylinder at the front of the truck in the "9 o'clock" position.

You didn't remove the distributor to do any of this, did you?

Yes, one should only do one such thing at a time, but it's difficult to go into the past without this

Andrew_shaw

Cusser I didn’t take the distributor out and it was all done gradually not all at once, over the course of like a month

Cusser

While I'm on "The Time Machine" kick, Yvette Mimieux was only 17 when filming took place

Andrew_shaw

Update I just took the distributor out and installed it again per the Haynes manual and for some reason it continues to looks like this, it’s a 1987 b2000 and I tried using the timing video but I couldn’t make heads or tails of what I’m doing wrong with this truck

MazdaMitch

Despite what some people may say pulling the distributor and putting it back in correctly is difficult.

I once spent three days on it trying to get it like it was from factory which means having it basically in the center with the bolt in it that way you can advance it or retard it you have leeway.

I have gotten lucky when we redid the head gasket on Jason's truck I put it in correctly the first time.

The way yours is right now it's a tooth off so it'll only run in the all the way one way or the other.

Try again.

Cusser

The angled gear teeth cause the distributor rotor and shaft to rotate as one presses it into place, so when at TDC #1 one must start out with the rotor pointing at about 11 o'clock so that it will end up in the correct position about 9:30.

Mrcrowley

Cusser how the hell do I get 9:30 on my distributor lol jk I no what you meant

Axel-Breaker-Earl

There is also some indicator marks to "line" the Distributor up BEFORE you install it.

There is a "Dot" on the distributor shaft GEAR.......and a cast-in "Line" on the lower end of the aluminum distributor casting. Align these together FIRST, then hold only the aluminum distributor CASTING at the top portion of it and maybe on the hold down plate. Point the distributor gear end toward the distributor hole in the head, and insert the distributor into the hole while keeping the CENTER of the adjustment slot on the distributor base, aligned with the THREADED HOLE for the distributor securing bolt. Once the distributor is pushed all the way into the head, your rotor should be pointing to 9:00 (or up to 9:30) o'clock.......and the securing bolt will be in the center of the adjustment slot.

You will still need to set/adjust the spark (or ignition) timing after the distributor is installed. If you set the spark timing to 6° BTDC as the factory suggests, the securing bolt should be close to the center of the adjustment slot.......within a 1/4 of the center for sure.

If your securing bolt is NOT in the center of the adjustment slot, and your spark/ignition timing is at 6° BTDC........then the timing belt could be off a tooth. If you check the timing belt install, and all is correct with it, the the outer ring of your Harmonic Balancer (HB) has slipped, and the timing mark on the HB has rotated and is no longer accurate.

I never use the timing scale on the lower timing belt cover to set my engines to TDC........I remove the lower timing cover and align the "NOTCH" in the crankshaft timing gear with the cast-in "LINE" on the front of the oil pump. If you do this, you can then reinstall the lower timing cover and see if the timing mark on the HB is correctly aligned with the TDC mark on the timing scale.......if it is, your outer ring on the HB has NOT SLIPPED ANY.

Taking this one step further.......there is a common condition with the B2000 & B2200 engines where the crankshaft KEYWAY can become "Wallered Out". You can't tell if this has happened until you remove the 21mm crankshaft bolt, and slide the lower timing gear (that the HB bolts to, with the six 10mm bolts) off of the crankshaft snout and visually inspect it. Once that keyway slot becomes damaged, you won't be able to accurately set your crank/cam timing or your spark/ignition timing.