Electric Issues

[Zeusimo]

I'm Having Some Electricity Problems On My 620

 

Symptoms:

Whenever I Turn My Headlights On Or Windshield Wipers On It Turns Off At Stop Signs If I Don't Keep The Revs Above 1.25k

It's Really Hard To Start If The Lights Are Turned On When I Turn The Key, And Then After It Starts It Would Shut Off Immediately

And It Often Misfires When Starting I'm Beginning To Move

 

This ONLY Happens When The Lights Are Turned On And The Windshield Wipers

 

I've Recently Noticed This As It's Starting To Rain And Get Dark Earlier

 

Does Anyone Know What's Wrong??

I Think The Alternator Is Bad, Maybe The Battery?

[elmerfudpucker]

voltage regulator?

[260zkaboom]

Your alternator isn't keeping up with your power usage when you are using headlights and wipers.

Take out the alternator and have it checked out at an autozone or other place that will check it out.

Check with the parts place to see if you can upgrade to a maxima or 280z alternator that has more amps at idle.

 

Approximate amp draw is just under (according to fuse limits)------ 15 for ignition, 15 for wipers, 7-10 for each headlight.

 

So with all that going on, the stock truck alternator is maxing out at 35-38 stock I believe........

 

Skib, Icehouse, or Bleach may have more exact info on amperages of the alternators.

 

Also make sure the top of the battery is clean, dirt will cause a parasitic drain.....throw away the rag/paper towel and wash your hands right away ,

if not the acid will transfer to your clothes and magically will have cooling holes next time you wear them ( from experience ......duh).

[260zkaboom]

I think that year has internal regulator I believe.

[banzai510(hainz)]

buy a volt meter for the truck so you can see whats happening with the electrical system if its loading down.

Even the plug in the cig type work good enough. thats what I use on my 521.

 

clean conts on battery

buy molded battery cable not the 3pc type that get corrossion.

if external volt reg get a solid state unit type if possible.

load ck the alternator

 

damn nice truck you have!!!!!!!!!!

[datsun brat pack]

78 and up have internal regulatior's 30amp 720 84 and up have 50amp's:D

[Pacific coast Datsun]

Sounds like a bad alternator. If so it's a perfect time to upgrade to one that puts out more amps.

I went with one meant for a 81 510. It puts out 60 amps & youll need to run a smaller belt or swap the alt. pulley [if possible].

If yours is an internally regulated alt. it should be a plug in & go swap. If not theres 2 wires that go to the voltage regulator that get cut & then get spliced to the T plug on the back of the alt.

[deadmonkey]

78 is INTERNALLY regulated. I went round and round with Shucks with that crap. From '77 to '78 they went from external to internally regulated... so MAKE SURE you get an internally regulated alt.

Perhaps check for power drain? It sounds like there may be a partial short, though I would think a fuse would blow with that kind of short. Maybe check to make sure somebody didn't oversize some fuses to keep them from popping?

 

Manual says at idle with lights on high and heater fan on high you should have 12.5 V at the battery.

 

I would check the battery first. If you have a known good battery, plop that in and try it. If not, take out the battery and charge it before taking it in to have them test it, otherwise you will have to wait for them to charge it before they can test it. Like Hainz said, clean the contacts on both ends, if corroded.

 

Make sure they know the Alt is internally regulated if you take it in. I was given some BS once that when they tested mine, they use their own regulator on the machine and the machine said it was fine when in reality all it tested was the wiring, not the charging circuit. They are retards at those stores! It took them 10 minutes to find the 'T' shaped plug for their testing machine.

 

Be aware of changing out the pulley on the alternator as you might void the warranty. They mark those with yellow paint to make sure. My alt is HUGE and barely fits in there. I simply got a 1.5" bigger belt and it barely fits in there! I think the little hitache (or was it Mitsubishi?) one is the proper size replacement...

 

but make sure and pop out the bushings in the alt mounting for the old one BEFORE you take it in for the core... You will need those to make the new one fit properly!!

[metalmonkey47]

Take out the alternator and have it checked out at an autozone or other place that will check it out.

 

You don't have to take it out to have it tested ;) We carry a neat little tool that puts a drain on the charging system and tweaks the charging system to test it. It's as accurate as throwing it on the tester inside. The same tool will do a starter test AND battery test.

[Zeusimo]

Thanks For The Replies I'm Gonna Have It Tested Since I Have Cavemen Tools

Thinking Of Upgrading Alt

What Alts Just Bolt-On (I Know That's Impossible)

I'm Beginner With Electricity

Maybe This One?

http://community.ratsun.net/topic/18218-how-to-install-a-saturn-alt/page__p__251785__hl__alternator__fromsearch__1#entry251785

I Just Can't Make My Own Pulley

[banzai510(hainz)]

620 trucks use the smaller alt cause the idler arm is slightly in the way it will hit up against it when fully extended

[Pacific coast Datsun]

"What Alts Just Bolt-On (I Know That's Impossible)"

 

I used one for a 81 510. Fits the L series Alt. mount w. no mods needed. I went with a belt thats slightly bigger & the Alt. is about 1/2 inch from the idler arm.

[Zeusimo]

"What Alts Just Bolt-On (I Know That's Impossible)"

 

I used one for a 81 510. Fits the L series Alt. mount w. no mods needed. I went with a belt thats slightly bigger & the Alt. is about 1/2 inch from the idler arm.

 

I Went For Your Suggestion And Thats A Small Half Inch!!!

It Also Hits The Water Hose

[datzenmike]

To move the lower rad hose get a water inlet from a Z car with the inline six. It's swept back more and makes more room for the larger alt. I found this out years ago before the inter netz. Also try a 720 lower mount to block. I think the mount positions the alt. slightly lower and this allows it to swing back and under the rad hose better.

 

.

 

 

 

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[Pacific coast Datsun]

I Went For Your Suggestion And Thats A Small Half Inch!!!

It Also Hits The Water Hose

Thats odd but i believe you. I forgot to mention that i used a thick zip tie to pull the lower hose out of the way a bit.

[Zeusimo]

Autozone Tested It And They Said It Passes With Flying Colours!!!

I Said BS Theirs No Way That Thing Passed

So I Bought It ($57.43) And Put It On, I Was Surprised That I Was Able To Use The Stock Belt

 

I Just Got Back From School And I Drove With High-beams On (Just To Test)

NO Misfiring, Or Stalling

And It Doesn't Make This Weird High Pitch Whistle When I Turn The Lights On Anymore

Before Volts Would Go From 14.35 To 12.13 After I Turned On Everything

Now Volts Go From 14.4 To 14.25 After I Turned On Everything

 

Old 30A??

 

New 60A!!

 

Used Some Kind Of Hard Plastic String To Pull Back Hose (Temporary)

 

A Finger!

[banzai510(hainz)]

Zeusimo

alot of parts stores only ck for voltage and dont ck for a load.

They propable got the correct voltage but hit the cig lighter and watch it drop to nothing!

NAPA i used to go to had a load tester.

 

As for the rad hose I would try to find a metal band that can fit around it or even cut a Campell soup can and get a radiator clamp to hold it on so in case you hit(the blades) the alternator youll hear it instead of a tiny hole thus leaking water thus head warp /gasket change ect....... as the belt stretches it will come closer.

 

Im not positive depending on alternator mount that go to the block the pivit point might be closer or not thus extending the alternator to the idler arm.

I myself have a 50amper on a 521 and i grinded the idler nut for soem extra room.

[deadmonkey]

This is exactly why I went round and round with those guys about my Alt... Fing pissed me off so much I don't go there anymore.

 

It amazes me that they don't load test those, because the regulator has to have load for it to kick in a charge.

[Pacific coast Datsun]

Glad it worked out for you! Hainz has a good idea regarding getting that lower hose away from the alt. blades. Fortunately my zip tie is still holding but ill prob make some adjustments.