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Throttle cable stuck?


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#1 FunkyFresh520

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Posted 04 December 2016 - 03:04 PM

I have a 67 datto pickup and one morning wen i was goin to work i was pumpin the gas pedal to get it started and the pedal became loose. The cable is pretty much not returning back when i push the throttle. Does anybody know how i can fix this ?

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You can see here how it stays stuck with the throttle open
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#2 flatcat19

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Posted 04 December 2016 - 03:22 PM

When poorly grounded the electrical system will use the throttle cable as the shortest path to ground.

Verify you have good, and a few, ground from battery to engine, frame, and body.

Then you will also want a new accel cable.
You may be able to free yours up to work, but the damage has already been done.

You can't hang if your nuts haven't dropped...it's physics


#3 FunkyFresh520

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Posted 04 December 2016 - 03:31 PM

When poorly grounded the electrical system will use the throttle cable as the shortest path to ground.

Verify you have good, and a few, ground from battery to engine, frame, and body.

Then you will also want a new accel cable.
You may be able to free yours up to work, but the damage has already been done.


I dnt see how anything electrical is related to a accel. cable? I dnt get it

#4 flatcat19

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Posted 04 December 2016 - 03:45 PM

Battery grounds to engine. Right? From there the path needs to find a final destination. Engine can't be grounded because it sits in rubber isolators, right? Where's ground?

If there is no ground/bad ground to body and/or frame electricity will find the shortest path to ground. Your accel cable is that path to body ground.

The ground you walk on is electrically charged. Every electrical anything needs ground to complete circuit.

Want to test this? Remove ground cable from engine that connects to battery. What happens?

You can't hang if your nuts haven't dropped...it's physics


#5 wayno

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Posted 04 December 2016 - 03:57 PM

What was said was not said clearly, if the engine block ground to the frame/battery was removed or has been severed the throttle cable can become the ground, when this happens the cable is so small it acts like a fuse of sorts and gets smoking hot and melts the throttle cable sleeve which in turn jams the throttle cable, this is a common issue on 60s Datsuns.

Your cable might have just broken, you need to pull on the cable inside the cab and see if it comes all the way out, if it does you need a new throttle cable, if it doesn't then you need to remove the complete throttle cable and find out why it is jammed up, melted, broken, bent cable, ect.


 

 

 


#6 datzenmike

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Posted 04 December 2016 - 03:59 PM

The engine, transmission, leaf springs, shocks are all rubber mounted so the drive train is basically insulated from the body. I had a 521 when I was younger with no ground to the body and like most Datsun owners no battery tie down. Battery tipped over and the positive battery terminal touched the fender. Power found a path to the engine (ground) through the throttle cable. Presumably it glowed orange hot before I could tip the battery up. The hot cable melted the plastic sheath and ... welded it together when it cooled. Naturally this was in the idle position.

 

Yours may have damage from accessories grounding down the cable and accelerated the wear, I don't know. I have also had the cable fray inside and become tight to pull and won't release. This was from having too tight a bend in the cable.

 

 

First...  Disconnect the cable and pull each way... is it sticky or loose?

 

If loose, check to see if it's not the cable but that other linkage the cable is attached to.

 

Then see if it's the throttle plate on the carb hanging up.


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#7 Dolomite

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Posted 05 December 2016 - 06:38 AM

It could just need lube.
Chrome door handles are under rated.

#8 Stoffregen Motorsports

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Posted 05 December 2016 - 01:56 PM

Remove the cable. Hang it from a piece of wire. Squirt some WD40 on the cable and let it sit long enough to get inside the cable housing. Blow it out with air. Drip some oil onto the cable and let it sit over night (still hanging from wire so it runs down the inside of the cable housing). Check it in the morning.

 

Yes...WD40. Though I'm sure some crazy concoction like beagle pee mixed with molasses will work too.



#9 FunkyFresh520

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Posted 06 December 2016 - 12:08 AM

Lol wen i got time i will be looking into it

#10 FunkyFresh520

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Posted 26 December 2016 - 09:09 PM

When poorly grounded the electrical system will use the throttle cable as the shortest path to ground.

Verify you have good, and a few, ground from battery to engine, frame, and body.

Then you will also want a new accel cable.
You may be able to free yours up to work, but the damage has already been done.


I bought a new accel. Cable hopefully coming in this week. As for the ground issue how can i fix that?

#11 DanielC

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Posted 26 December 2016 - 10:07 PM

I am not sure about how the grounds are on a 520, but this is what is done on a 521.

Large negative battery cable goes to engine head.  A smaller pigtail comes off the negative battery cable, goes to alternator frame.  The pigtail is a minimum 10 gauge, for a 35 amp alternator.  Larger alternator, bigger pigtail wire, lower number gauge.

A second 10 gauge, or larger wire goes from alternator frame to a bolt holding the voltage regulator to the inner fender.

 

I would also run a short jumper ground wire on one of the rubber motor mounts, connected to the engine side of the mount, and the frame side of the mount.



#12 FunkyFresh520

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Posted 26 December 2016 - 11:07 PM

I am not sure about how the grounds are on a 520, but this is what is done on a 521.
Large negative battery cable goes to engine head. A smaller pigtail comes off the negative battery cable, goes to alternator frame. The pigtail is a minimum 10 gauge, for a 35 amp alternator. Larger alternator, bigger pigtail wire, lower number gauge.
A second 10 gauge, or larger wire goes from alternator frame to a bolt holding the voltage regulator to the inner fender.

I would also run a short jumper ground wire on one of the rubber motor mounts, connected to the engine side of the mount, and the frame side of the mount.


Im confused bro im sorry hhaha

#13 DanielC

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Posted 26 December 2016 - 11:46 PM

I can get you some pictures in the next day or two.



#14 kelowg

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Posted 27 December 2016 - 06:09 AM

Ground batt to body,body to frame,batt to head or block. Some even ground bed to frame. That and batt to alt.



#15 flatcat19

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Posted 27 December 2016 - 10:26 AM

You can never have enough ground.

You can't hang if your nuts haven't dropped...it's physics


#16 KoHeartsGPA

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Posted 29 December 2016 - 03:16 PM

Starter bolt to chassis, cab and bed to chassis, head to radiator, block to chassis on other side for good measure.

#17 240zness

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Posted 29 December 2016 - 05:34 PM

And maybe one of those things dragging on the ground off your chassis

#18 datzenmike

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Posted 29 December 2016 - 05:43 PM

I ran a thick wire with lugs soldered on the ends, to the engine bracket bolt and to the engine mount bolt. It's only maybe 6" long and you can't even see it. This is my 710 so this is the same as battery ground to body sheet metal. On a truck this would only ground the frame. The cab, fenders and box are rubber isolated so don't assume everything is well grounded. But with the frame solidly grounded you can easily ground these separately.


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