Datsun down

[Laecaon]

If you have the fusable link (at the starter)

 

Not too sure if fivetwenty1's have this, but a 510 will lose all powar

 

No, the starter can always be jumped!!! Yes it will cut key power to turn the starter. But you can always jump the starter with a screw driver. Always.

[Guest 510kamikazifreak]

Imma head over there, she is only 2 miles away and the Hondar haz tow hook :thumbup: :thumbup: :thumbup:

 

I like this...tow her home...

Never leave a Datsun on the side of the road..

They aint no hookers...

 

:rofl:

[Guest 510kamikazifreak]

No, the starter can always be jumped!!! Yes it will cut key power to turn the starter. But you can always jump the starter with a screw driver. Always.

 

still wont run

[Jayden71]

No, the starter can always be jumped!!! Yes you can get key power to turn the starter. But you can always jump the starter with a screw driver. Always.

 

Gotta be loose wire somewhere then.

[Guest 510kamikazifreak]

Gotta be loose wire somewhere then.

 

if it were here.

 

I would make sure it made it home for yah Jayden

[Jayden71]

if it were here.

 

I would make sure it made it home for yah Jayden

 

Awwwwwwwwwww :console:

 

 

Headin oot to get er home. Wish me luck my Datsun fate is in my wifes hands :w00t:

[I'm BLUE]

do you have a mechanical fuel pump ? (if failed/completely blown ...)

oil smell like gas really bad ?

 

I saw your status saying KA pump installed recently.

 

 

Yes electrical stuff mentioned is usually first :-/

 

My next guess would be an alternator charging check and a fast compression check (if you think you dropped a valve ... referring to the "slap slap slap")

[Jayden71]

do you have a mechanical fuel pump ? (if failed/completely blown)

oil smell like gas really bad ?

 

I saw your status saying KA pump installed recently.

 

 

My next guess would be an alternator charging check/compression check (if you think you dropped a valve ... referring to the "slap slap slap")

 

mechanical fuel pump KA oil pump. All spark plugs were normal, no black no fuel smell. all same color

[Guest 510kamikazifreak]

Awwwwwwwwwww :console:

 

 

Headin oot to get er home. Wish me luck my Datsun fate is in my wifes hands :w00t:

 

 

You will get her home...

 

:thumbup:

[Jayden71]

Got her home and got a bigger screwdriver and starter cranked engine. She cranked fine but would not fire. No weird noises or anything. Few farts from carb but sounded normal. Wonder if coil went out???

[Laecaon]

Your key wont crank it?

 

I wonder if your ignition switch is bad.

[I'm BLUE]

*test for pulse feedback from your ignition module.

 

EDIT: *Grab your test light/multi-meter and check power to the ignition system first.

[Jayden71]

Right key wont crank strarter. How do I test for feedback??? Aww fuck I'm goin to bed. Take ignition switch out in morning and go from ther

[mklotz70]

hhhmmm......I'd be looking for a missing ground. My first thought was the chassis to tranny ground strap down by the starter, but if the batt cables are connected correctly, that would have an opposite affect.....no electrical on any thing chassis related. Is your neg batt cable connected between the neg batt post and the engine block? Is is nice and tight? If you were missing a ground between the engine and batt, it wouldn't crank with the screwdriver trick. hhhmmm.....interesting problem.

 

FIRST.....pull the coil wire out of the dizzy end and lay it about a 1/4" from a good ground. This is sometimes easier to do with a phillips screwdriver pushed into the wire, then layed close to ground. Crank the motor....if you get a spark, the coil and matchbox are working and you don't have to worry about checking them. Move on to checking the plugs and plug wires. Do the same check at the end of each plug wire. If you have spark there, pull the plugs and use them instead of the screwdriver. More than once I've found spark plugs go bad and have no spark......just out of the blue. Anyway....

 

If you don't get spark, you can test the matchbox with a test light. It's operates the coil the same way the points do...turns ground on and off. Hook the test light clip to a good ground, turn the key on and put the test light on the pos post of the coil. Should be lit with the key on.....should stay lit when you turn the key to crank. If not, you have a key switch or wiring issue to deal with.

 

If that works, connect the clip of the test light to the pos term on the coil.....you're going to be looking for a ground now, so you want 12v coming in on the clip of the test light. Touch the test light to a good ground to make sure it lights up....you must have the key ON. Hold the tip of the test light on the neg term of the coil....use clips or a second set of hands......crank the motor. The test light should flash on and off. If it does, but you didn't get any spark from the coil wire, you may have a bad coil, bad wire, or you didn't have a good ground on the first spark test. If the test light stays on, remove the wire for the dizzy from the neg post of the coil.....touch the test light to the wire connector....if it still lights, I'd be moving toward the matchbox as being bad. If it didn't light or flash, crank the motor while the test light is connected to that wire. If it still doesn't flash, check to make sure you have 12v on the B term of the matchbox(reconnect the test light clip to ground for this check). If you do, I'd hook up a dedicated ground wire from the batt or chassis to the body of the dizzy before you call the matchbox bad. If it doesn't flash with the dedicated ground wire and 12v going to it, I'd call it bad(actually, I'd be taking it apart and checking the contact between it and the dizzy body). It's really common for them to not be getting a good ground.....it's pretty rare that they actually die.

 

If those tests work, check the neg term of the coil again(test light clip on POS).....it should not be lit. If it is, remove the wire/wires still connected to that term and check again. If it lights, you either have your test light connected wrong at this point or you have a bad coil....but that would be an extremely weird way for a coil to fail. If the term does not light, check the wires you pulled off.....if one of them lights up, it's shorted to ground somewhere and that's not good. The only two wires connected to the neg term on the coil in a stock 521 are one to the points(the C on the matchbox in your case), the other goes to a relay that puts the second set of points into the circuit to retard the timing(IIRC)(this wire should not be used in your setup). With the matchbox, you only need the wire going straight to the dizzy. If the wire to the matchbox flashed in the previous test, hook it back up to the neg term of the coil by itself(assuming there was another wire). Try starting it.

 

Hopefully, it's something simple like a loose connection somewhere. I'm out of time for now....hopefully all that will help someone, somewhere at sometime....even if not you :)

[Jayden71]

Thank you Klotzy!! Awesome info!! I will be doin some testing here after morning coffee :thumbup:

[Jayden71]

Power to coil = check

Power to Dizzy + check

Spark coming from wire when layed next to engine = check

Spark coming from plug when next to engine = check, blue spark

fuel in filters = check

smell fuel in carb = check

Pulled valve cover, all retainers are on, nothing seems amiss chain looks fine.

Just did oil change last week, oil still looks, smells like fresh oil

 

:confused: :confused:

 

I'm at a loss. Still can't figure why won't crank with key. It makes a small click nothing else. Screwdriver trick is gettin tiresome.

Cranks over nice, no backlash on starter

 

Gonna hafta rally the troops here in Boise to come help me :sneaky:

[wayno]

I had something like this happen to me recently when trying to start the truck, my guess would be that for me the engine was wet for the first time this summer/fall, I had gas, spark, timing was correct on everything, but it wouldn't run.

While it was trying to start, I grabbed the dist. and got hit several times, so I ask, how dirty are your spark plug wires and cap, if it got wet somehow while driving down the road and started loosing power and back firing, it could be that the dist. and wires are arcing across each other and basicly shorting out.

As for the starter turning the engine over when a screwdriver is used to JUMP the power from the positive battery cable to the starter exciter post, do not use the word short for this action, it confuses people, I would think the battery cable is good, but check it anyway for corrosion, try a differant one, also check you fuses, make sure they are all good, as there is no fuse to go threw when using a screwdriver, but there is a fuse to go threw when using the key.

Your positive battery cable goes directly to the starter solenoid, if it goes to the back of the alternator, then I am

surprised that you have not had a fire, unless the wire going from the back of the alt. to the starter is the same size as the battery cable itself.

[Jayden71]

Yes the battery cable from starter to back of alt is the same gauge as from battery to starter. Been like that for the 8 years I've had this truck. Nothin like this has happened before

[banzai510(hainz)]

521 dont have a Fusable link.

Yes the positive of alternator goes to the starter. This is common and most of us know this already. On 510s its a red wht wire. Yes it goes to tha volt reg also . Its always HOT. thats why be carefull pulling out a alt if the batter cable is still hooked up(use a plastic bag)

But anyways I dont think this has anything to do with it.

 

Ck the fuses. Im not positve if the key switch goes thru a fuse or not but ck. or replce the ignition fuse anyways and clean the connections.

 

Now Mklotz Wayno and Datzenmike gave pretty much all you need to know.

 

If you just take the wire and go from the =+batter to the selinoid it should crank the motor. If yes uyou either have a voltage drop across the key switch or the connection at the starter is loose , Recrimp or tighten the connector with seom pliers. Or maybe add a hot start relay.

 

Since you got spark and everything as you listed I would ck the valve lash on the rockers, swap in new plugs tighten the intake and carb bolts and try again,.

 

Maybe eve look at dizzy closer for wiggle or the bolt came out and dizzy is clocked far to one side going out of time.

 

Coils rearely go bad unless you hade the wrong one in there in the first place. Like running a Point coil w/o a ballast resisitor. If you do use a matchbox dizzy.

 

 

Im going to ASSUME the batter abd charging system is good on this.

 

I dont know where you get this timming jump quest. But you can alwasy but to TDC and ck the cam marks to confirm this and ck the rotor position.

[Jayden71]

I really apreciate all the info guys. I have Chester coming over and we are gonna finger this out, I miss my girl!!

 

I am running proper coil with dizzy. I have 60 amp external reg alt, charging system has been doin great. We will get it!!

[68Datsun510]

Matchbox bought from parts house 3 years ago

 

I got a blackbox dizzy before that did the same thing. The ignitor module (blackbox portion) went bad on it. The cheap ass reman ones do this. Swap the ignitor module with one from a known good dizzy.

[datzenmike]

 

If you just take the wire and go from the =+batter to the selinoid it should crank the motor. If yes uyou either have a voltage drop across the key switch or the connection at the starter is loose , Recrimp or tighten the connector with seom pliers. Or maybe add a hot start relay.

 

 

Get volt meter and pull the start wire off the solenoid. Have someone turn key to start and read the voltage on this wire. Bet it's under 5-6 volts. Now check the ignition switch out end. Just keep following back to find out why it's not 12 volts. If you can't fix, you can use this weak signal to power a relay like Hainz sez.

[HRH]

Matchbox unit took a crap I'll bet you. Check also for the clearance between the reluctor ring in the distributor and the corresponding 4 points on the dizzy shaft. Make sure there isn't a huge gap.

 

We can test matchboxes at NAPA. Don't buy one from us, you'll pay up the nose. But you can test, then try another from a wrecking yard. You're probably getting spark, but not in the correct arrangement, which is why it won't fire.

 

Also check the back of your ignition switch, to make sure that hasn't melted or come disconnected.

[Jayden71]

Runs like a champ.

[mklotz70]

Runs like a champ.

 

That's great, but I sure hope you're going to give us more than this as a follow up!