1. Welcome to PlowSite. Notice a fresh look and new features? It’s now easier to share photos and videos, find popular topics fast, and enjoy expanded user profiles. If you have any questions, click HELP at the top or bottom of any page, or send an email to help@plowsite.com. We welcome your feedback.

    Dismiss Notice

Ford 302 Alternator for plowing

Discussion in 'Ford Trucks' started by Plowformoney, Oct 6, 2006.

  1. Plowformoney

    Plowformoney Junior Member
    Messages: 24

    Higher amp alternator ?


    i have a 1991 F150 5.0L . When I shift from drive to nuetral and vise-versa. the motor almost dies and all my gauges shoot to the lowest position for a second. Is this my alternator? Idle control valve? I dont have a volt meter to test it.

    I will be putting a plow, lights etc on and I know I need to get a better alternator. Whats my current alternator rated at? What do I need to handle plowing?? Thanks guys!
     
  2. Brian Young

    Brian Young PlowSite Veteran
    Messages: 3,382

    Could be either one. I work on Ford every day and I've seen idle control valves go ka-put all the time. Or the alenator is shot. A stock alt. is I beleive, 85-110 amps. I know in my truck I beefed it up to a 140 amp altenator. Are you looking for a new truck? Mine is for sale and is basically brand new. (94 F150 heavy half ton all set up for plowing)
     
  3. Plowformoney

    Plowformoney Junior Member
    Messages: 24

    no thanks on the truck just bought this one.

    So will 140 be enough for plowing?
     
  4. Brian Young

    Brian Young PlowSite Veteran
    Messages: 3,382

    Yes and be sure to put a HIGH RESERVE capacity battery in it as well. NOT a High COLD CRANKING BATTERY ----A HIGH RESERVE CAPACITY BATTERY (your plow lights wont dimm as much!
     
  5. SnoFarmer

    SnoFarmer PlowSite Fanatic
    from N,E. MN
    Messages: 8,556

    A high reserve batt would be a Deep cycle Batt you DO NOT want a DEEP CYCLE batt.

    You want a batt with at least 1000ca and 750cca. Thinking about reserve?
    JUST ADD a second Batt.

    Sounds like a bad alt /voltage regulator/ short.


    Brian Young,
    A stock alt 85 to 110??? pick one it is not both..
    I bet the stock one is only 85amp.

    Up grade to the hight out-put alt.
     
  6. MickiRig1

    MickiRig1 PlowSite Veteran
    Messages: 3,617

    I would say it's your idle air control.
    They go bad ALL THE TIME. My trucks had 2 in 6 years- 30k miles. You can try cleaning the passages and lube the piston on the IAC. Most times it's a waste of time. Make sure none of the cables are loose in the mount or binding, spray with wd40 etc.. I even took a dremil with a cut off wheel and made a slot in the opposite end of the throttle plate stop / screw. This way I can turn the idle up and finish what I am doing if it dies again. Some times a bad idle can be the throttle position sensor but it would also have other issues then just idle.
    The volt gage and others will drop down when the idle is too low, the trucks on the verge of shutting down due to a very low idle.
     
    Last edited: Oct 10, 2006
  7. Plowformoney

    Plowformoney Junior Member
    Messages: 24

    could you describe where idle air control is? maybe a pic. Thanks man!
     
  8. Brian Young

    Brian Young PlowSite Veteran
    Messages: 3,382

    Well the new Decka battery I just bought for my 94 is a "high reserve capacity" battery and its not a "deep cycle" so I don't know what to tell ya. We use these "high reserve capacity " batteries in all of the cop cars we work on due to all of the electrical garbage we put on them! And my point to having a high reserve battery wasn't to start the vehicle it was so that the plow, when operating it, won't drain the battery power to the point where it stalls it out.
     
  9. SnoFarmer

    SnoFarmer PlowSite Fanatic
    from N,E. MN
    Messages: 8,556

    Good points . That is the same reason for the 2batts. There not for starting but to run the plow and garbage.... A plow can draw over 50amps, not counting all of the lights and electrical garbage plowers put in their trucks. more power.....
     
  10. Brian Young

    Brian Young PlowSite Veteran
    Messages: 3,382

    Yes 100% agreed a 2 battery system would be the way to go! And I believe Ford makes a reto fit kit just for the F150's
     
  11. MickiRig1

    MickiRig1 PlowSite Veteran
    Messages: 3,617

    The idle air control is right by the throttle plate on the passenger side of the intake. It has a oval flange with a cylinder attached at a right angle, 2 bolts hold it on , it has a two wire lead to it.
    It's probably still working somewhat, but not feeding the full amount of air to have a good idle speed.Most times when they totally die the truck will not idle at all.

    You can buy higher output alternators for your truck right off the shelf. You have to upgrade the output wire to the battery / batteries to do it right.
     
  12. Plowformoney

    Plowformoney Junior Member
    Messages: 24

    Well I took it off, clean it, and its still doing the same thing...hmmmm
     
  13. MickiRig1

    MickiRig1 PlowSite Veteran
    Messages: 3,617

    Like I said, sometimes you can clean the piece up and lube it and it will work. Or it will work for a little while. It's probably not opening far enough to get a good idle.
    I have had 3 Fords with EFI the newest a 2000. Even the 2000 has had it replaced at less then 50K miles. It's about a $65 parts at AutoZone or Advance stores for your year engine. The Ford stealer parts dept will charge you $110.