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what strength alternator would you recommend for a stock 1988 360 LA

Discussion in 'Pre-1994 trucks, commercial vehicles' started by upser145, Mar 4, 2017.

  1. upser145

    upser145 Member

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    bone stock except exhaust. thanks for the help
     
  2. upser145

    upser145 Member

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    trying not ot order one because of time restrains and and hhaveing no luck finding a 360 alternator i could get in less then two weeks, if i happen across a 318 alternator i assume it wouldn't work. i know a v6 alt wouldnt work obviously but not sure about a 318 figured it would be worth a shot
     
  3. pt006

    pt006 Active Member

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    There were 4 alternators available for 1988 dodge pickups. A nippondenso 75 Amp and a 90 Amp. ---- Or a Chrysler 90 Amp and a 120 Amp. Unless your truck came equipped with a 120 Amp alternator from the factory, do NOT use one to replace yours. Since you have a stand alone regulator, I think any of the 3 other choices should work. Remove the regulator from the firewall and clean off any rust to verify a good ground. I believe V-6, 318, and 360 alternators will interchange. Check the listings from Auto Zone or Advanced Auto etc to verify. The Chrysler Alt. has a cover on the backside, nippo does not.
     
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  4. RalphP

    Level 2 Supporter

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    Why not?

    That's what I did on my 1988 Dakota; seems to work fine, although the voltage at charge is about 14.2V or so.

    RwP
     
  5. PCRMike

    PCRMike Well-Known Member

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    On the D series trucks, putting a bigger alternator on it is not safe. Under normal circumstances it gives no issue. Say he leaves the headlights on and drains the battery. Gets a jump and barely gets it started. The H.O. alternator will be at full output charging the battery. The smaller gauge wire can overheat, melt, short, catch fire, etc. Not worth the risk without other system upgrades.
     
    Bob Lincoln likes this.
  6. upser145

    upser145 Member

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    al a altetnator off a 88 v6 would would?
     
  7. valiant67

    valiant67 Rich Corinthian Leather
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    I think the wiring is all the same for the "newer" family of alternators from the late 80s, no matter the voltage. That is unlike the earlier cars with the 100 amp monster.
     
  8. AllanC

    AllanC Well-Known Member

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    I reviewed a wiring diagram for a 1988 D150 equipped with 360 V8. Wiring layout and routing appears identical between the 40/90 alternator and 50/120 alternator. Alternator output control is through a separate voltage regulator mounted on the firewall.

    There is a note in the schematic that indicates 8 gauge wire for 40/90 alternator and 6 gauge wire for 50/120 alternator. So as others have suggested if you used the 120 amp output alternator you should run an additional wire from the alternator battery terminal to the battery. You would need to consult the wiring diagram to see all of the splices that alternator battery wire to battery makes on its path.

    Since that is a carburetor equipped vehicle, there is no electronic fuel injection along with electric fuel pump so electrical demand is less than modern vehicles. A 75 / 90 amp alternator should be more than adequate. It is easier to access brushes on the Nippondenso unit for replacement than on the Chrysler designed alternator.
     
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  9. upser145

    upser145 Member

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    Would a nippondenso alternator work if Chrysler was orginally on part store ordered wrong part neeed to know if i need to cancel order
     
  10. Bob Lincoln

    Bob Lincoln "CHECK FAULT CODES"
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    I would NOT run an additional wire from alternator to battery. Instead, I would run a single, larger wire, such as the 6 AWG mentioned. Running parallel wires, especially of a different wire gauge, will result in different voltage drops and therefore can create problems with reference voltages. This is especially true of ground wires.
     
  11. RalphP

    Level 2 Supporter

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    Ah.

    Not a problem for me; I was redoing The Big 3 also.

    RwP
     
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  12. AllanC

    AllanC Well-Known Member

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    The 4 electrical connections on the various alternators for that model year (Denso, Chrysler) are all the same orientation. Also I strongly believe the mounting ears and spacing and belt alignment on the double V belt drive would all be the same and interchangeable. About the only problem issue that could arise is if you order a replacement alternator from a retail auto parts vendor you would be expected to return a like alternator to get the core credit. In other words if you are replacing a Chrysler alternator the retailer would want a Chrysler alternator for exchange. If replacing a Denso alternator the expectation would be to exchange a Denso to get core credit.
     
  13. upser145

    upser145 Member

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    Well I replaced alternator and it didnt seem to fix my problem. when it started I was going down the road and i felt like it didnt have any power and when I got on it some it just cut off and wouldn't crank like it was dead so i figured alternator, got pulled home replaced alternator jumped my dead battery off and it ran for a minute or two and died I jumped it twice after that with it dieing shortly after start now it won't crank even with a jumpstart it'll turn over but it won't crank. So at this point I'm guessing I need a battery
     
  14. upser145

    upser145 Member

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    what would my voltage regulator look like? I'm assuming it would be on the firewall i see a gray box and a black box im not sure what they are im thinking one of them is probably it
     
  15. Bob Lincoln

    Bob Lincoln "CHECK FAULT CODES"
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    Don't shotgun this. Do proper diagnostics and it will save you time and money.

    First step: fully charge the battery, let it sit a couple of hours, then load-test it. Auto parts stores will do that for free, or you can put it back in the truck, measure the voltage (should be about 12.6V with engine off). Then turn on the headlights and measure the voltage after 10 minutes. Should still be above 12.0 volts.
    If the battery is good, you have another problem. Voltage regulators rarely fail. Not sure if it's integral with the PCM in your truck - it was for most cars of that vintage.

    You should also thoroughly clean the battery posts and the clamps, and examine where the cables meet the clamps for corrosion under the insulation. When you reinstall the cables to the battery, turn on the headlights and measure voltage between the positive post and positive clamp, and between the negative post and negative clamp. With engine off and headlights on, you should not get more than 0.1 volts. If you do, you have a poor connection. Also with engine off and headlights on, measure voltage between the engine block and the negative post, should not be more than 0.1 volts. If it is, you have either a bad ground cable or connection.
     
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  16. AllanC

    AllanC Well-Known Member

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    This truck has the 5.9 / 360 V8 with 4 bbl carburetor so NO electronic fuel injection and no ECM (engine control module). So the voltage regulator is stand alone and probably located on the firewall. Here is a link that shows images of the voltage regulator. Make sure the case of the voltage regulator is grounded to the body. A better ideal is to run a short wire from the case to the battery negative post to insure proper grounding.

    voltage regulator 1988 dodge d150 pickup - Google Search (at https://www.google.com/search?q=voltage+regulator+1988+dodge+d150+pickup&espv=2&tbm=isch&imgil=nas88-Q46SqtSM%253A%253Be_8xR4X4wJoO2M%253Bhttp%25253A%25252F%25252Fwww.ebay.com%25252Fsch%25252FDodge-D100-Voltage-Regulators%25252F33577%25252Fbn_1365573%25252Fi.html&source=iu&pf=m&fir=nas88-Q46SqtSM%253A%252Ce_8xR4X4wJoO2M%252C_&usg=__VxVQ3ukk3g3xw2w2sNfo2tBkmTM%3D&biw=1059&bih=663&dpr=1.25&ved=0ahUKEwi0yJ-91MfSAhUG6CYKHQuADHcQyjcIRA&ei=013AWPSSDIbQmwGLgLK4Bw#imgrc=nas88-Q46SqtSM ):

    Bob L gave excellent tips for checking charging system problems. Follow them.
     
  17. upser145

    upser145 Member

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    it was the battery thanks guys
     
  18. page2171

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    I'm copying this for future reference...just in case I need it. Thanks!
     
  19. upser145

    upser145 Member

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    well I put a new battery in it and it worked until today it died once again going up the road. but Ive put in a brand new alt and battery I'm not sure what else it could be especially since it seemed to work for about a week
     
  20. upser145

    upser145 Member

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    the alternator I bought was a reman so I'm thinking maybe when I put the new battery in it it made up for the alternator not charging as strong as it was supposed to but like i said i drove it for a week during the day and at night with lights on and everything worked good until today. could my idle be to low for it to charge good possibly? the fact that it worked great for a week confuses me. the only elctrical thing i did since i got it working is yesterday I put a fuse in for the heat and ac as i had taken that fuse out awhile back and not replaced it but I dont see why putting that fuse back in would suddenly make it die.
     

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