New battery and starter, not starting 98 f150

ford
suspension

#1

Hi folks,
My truck is a 98 f150 5.4 ltr. It had been kind of funny starting on really cold days this winter(sometimes wouldn’t fully turn over so I had to push on gas while turning key to start it) and one afternoon last week when I went to turn it on it wouldn’t start. I got it towed home and replaced the starter which had a broken wire on it (the braided copper wire). It did not start after that. We jumped it and it started one time, but very weakly and died after about one minute. I then got the battery tested and they said it was bad so I replaced it and it still did not start. Jumped the new battery to make sure it was good and still no go. When I turn the key I can hear juice for a moment and a click, but I cannot hear the starter spin and thats all it does.

I checked out the fuses, the starter connections, checked and cleaned the connections on the battery.

I have to decide tonight if I’m going to try to diagnose and fix it tomorrow or have it towed to a shop. What I need to know is how to test/diagnose anything that might be keeping it from starting so I can be fully prepared to get it fixed tomorrow(nice warm day). Please and thank you for any help!
Aaron


#2

The problem might be with the starter relay.

http://www.rockauto.com/catalog/moreinfo.php?pk=1005849&cc=1315033

Take a set of jumper cables and with either the red or black clamps jump the two large terminals on the relay. If the starter operates replace the relay.

Tester


#3

Clean and check the ground connection from the battery on the engine block. While you’re at it if there are any swollen places on the cable indicate a cable comprimised by corrosion and needs replacement.


#4

I think that we already did basically the same thing. I friend used something like a screwdriver, dont remember exactly what he used, but he connected the battery to the relay and it still didn’t start.


#5

I m more familiar with older ford trucks, but this sounds similar to when my voltage regulator failed


#6

First thing I do in a no-crank situation is measure the voltages on both starter terminals, from the terminal to starter case. If both are above 10.5 volts during attempted cranking and the starter doesn’t spin, the starter motor has to come out and bench tested or if you are sure it is bad, fixed at your local auto-elec shop (that would be my choice) or replaced with a new one.

If either is below 10.5 volts, put on your detective hat. You need to find out why.


#7

I hate to say it, but does the engine turn? Can you put a wrench on the crank bolt and turn the crank?


#8

are you sure there are no corroded connections? or cables?


#9

Ok so I ended up taking it to a mechanic. He discovered that the ac compressor was frozen up and keeping the engine from starting. He replaced it and problem solved! I’m glad I took it in instead of spending more time trying to figure it out myself bc I would have never thought it was something like that. He said he took off the serpentine belt after he found it frozen up and the engine started right up so he knew that was the problem. Thanks for the input everyone!