1987 Chevy v10 parasitic draw

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Cdog_96

Member
Joined
Jan 15, 2022
Posts
45
Reaction score
31
Location
Aiken
First Name
Clay
Truck Year
1983
Truck Model
K10
Engine Size
454
Hey guys, so I am restoring a 1987 Chevy v10 with TBI, the truck will sit overnight and the battery will be completely dead next morning. I noticed the ECMB and horn/dimmer fuse are constantly hot with the truck off. Any tips on how to locate the draw ? If it's one of those two circuits how to remedy it? Any help appreciated thanks !
 

Ricko1966

Full Access Member
Joined
Apr 11, 2017
Posts
5,387
Reaction score
8,594
Location
kansas
First Name
Rick
Truck Year
1975
Truck Model
c20
Engine Size
350
Pull the fuse put a 194 bulb and socket in place of the fuse,if the draw is there the bulb will light. Now start disconnecting everything on that circuit until the light goes out,when the light goes out you found your problem.
 

Attachments

  • Screenshot_2024-05-05_214402.jpg
    Screenshot_2024-05-05_214402.jpg
    57.8 KB · Views: 34

Matt69olds

Full Access Member
Joined
Jan 8, 2018
Posts
2,447
Reaction score
3,816
Location
Central Indiana
First Name
Matt
Truck Year
81
Truck Model
GMC 1/2 ton
Engine Size
455 Olds
Watch this:

xc_hide_links_from_guests_guests_error_hide_media

If you pull all the fuses and the draw is still there, disconnect all of the alternator wiring. If the draw is still there, then something is wired that isn’t fused in the fuse box. If the draw is gone with the alternator disconnected, you have a leaky diode in the alternator.
 

Cdog_96

Member
Joined
Jan 15, 2022
Posts
45
Reaction score
31
Location
Aiken
First Name
Clay
Truck Year
1983
Truck Model
K10
Engine Size
454
Watch this:

xc_hide_links_from_guests_guests_error_hide_media

If you pull all the fuses and the draw is still there, disconnect all of the alternator wiring. If the draw is still there, then something is wired that isn’t fused in the fuse box. If the draw is gone with the alternator disconnected, you have a leaky diode in the alternator.
So the alternator is hot to touch with vehicle off, disconnected it this morning and will confirm if that stopped the voltage drop this afternoon. I am assuming that is the problem, I have a wire running from back of alternator to the starter lug and the plug is plugged in back of alternator. Is this correct for the wiring? Kind of stumps me because it is a new AC Delco alternator
 

Latest posts

Forum statistics

Threads
44,096
Posts
949,228
Members
36,184
Latest member
Swanpcat
Top