Question good batteries good starer good altenator low voltage wont turnover

kato79

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New to the ford community hello everyone I have issues already. New batteries good connection new alternator starter tested good cranking like batteries are dead. With key on battery gauge reads about 10 volts when the gpr relay clicks on voltage drops to about 9 volts before even trying to crank it so of course it won't even turn over at that low voltage. Tried everything I could think of need help suggestions anyone?

PS: Recently bought the truck from original owner almost immaculate condition first ford ever owned heard they were good trucks did it for the diesel.
95 7.3 psd 184000 miles
5 spd
4.10 gear front and back
Xtra stiff rear suspension
4x4
 
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01yellerCobra

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First thing I'd check are all the grounds. It sound like one of them is bad. Also, were the cables themselves replaced?

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DaveBen

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I agree with yellercobra, check the cable ends and especially the grounds. More probelms are due to bad connections. The low voltage tells me that you have some corroded connections. You should see 12 v when you turn on the key after the glowplugs cycle.

Dave ;tu
 

Crumm

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Define "new batteries". These trucks require high cca batteries that are fully charged. If they are tip top shape then cables may be coroded inside the insulation.
 

JLDickmon

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New to the ford community hello everyone I have issues already. New batteries good connection new alternator starter tested good cranking like batteries are dead. With key on battery gauge reads about 10 volts when the gpr relay clicks on voltage drops to about 9 volts before even trying to crank it so of course it won't even turn over at that low voltage. Tried everything I could think of need help suggestions anyone?

PS: Recently bought the truck from original owner almost immaculate condition first ford ever owned heard they were good trucks did it for the diesel.
95 7.3 psd 184000 miles
5 spd
4.10 gear front and back
Xtra stiff rear suspension
4x4

the right way to do this, is to perform a voltage drop test.
I wrote this up years ago, and the basics are the same except you'll be dealing with all big cables..

So run to Harbor Freight or Sears and get a decent meter, and pick this thread up on about post #58.. about halfway down the page..
http://www.superdutydiesel.com/forums/showthread.php?23955-Missing-no-power/page6
 

JLDickmon

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and yes, you can "drop test" both the power AND ground sides of the circuit!
 

westquest

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Hi all having the same problem but mine turns over real slow. Also is there supposed to be power going to my starter with the key off? If not any ideas what it could be. P.s I replaced the glow plugs but not the GPR and it has not started since. Thanks for replying. PPs I also have a 95 7.3 turbo charged diesel.
 
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BIG JOE

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Hi all having the same problem but mine turns over real slow. Also is there supposed to be power going to my starter with the key off? If not any ideas what it could be. P.s I replaced the glow plugs but not the GPR and it has not started since. Thanks for replying. PPs I also have a 95 7.3 turbo charged diesel.

20 year old electrical/starting system ?

First thing to do would be to Load Test each battery.. individually.. completely isolated from ANY load source. If either is weak... replace them Both.

Then inspect the cables and clamps for corrosion.

Replace the GPR.

Give it a try.. if no start.. get back to us ?

Joe
 

westquest

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Never mind the Message I sent you Joe. Checked the Batteries both are good. There is some corrosion in the wires. Also is it normal to have 2 starter solenoids? One on the side and one on the starter? Also no voltage regulator? What can I say it is my first diesel.:)
 

DaveBen

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The alternator is internally regulated, so no separate regulator. Clean all of the corrosion off the wires/connectors. This just adds resistance to the circuit and that is not good. Diesel engines need a LOT OF POWER to get started when it is cold. So everything you can do to help the starter will help. What do you mean by the batteries "Checked good"? They should be load tested individually. Let us know how this goes.

Dave :)
 

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