Fixing a 7.3 that wont crank

[boggerted]

im getting a 1989 F-superduty that has a 7.3 idi and zf5 trans. The thing im trying to diagnose is, it wont crank. When you turn the key to start, it just clicks. The batteries are charged, the fender mounted relay has 12v on both sides when in the start position, and I tried tapping the starter amd solenoid on the starter. what else should I check? Also, I tried jumping the solenoid on the starter with a screwdriver, but it just sparks, no crank.

 

[towcat]

sounds like a bad starter. BUT.....just for ***** and giggles....bar over the motor to make sure it isn't seized up. 15/16"(iirc) socket on the front of the crank bolt is a good place to make sure it turns over. where is the truck at and how much is the asking price? they aren't worth much in some states due to the high registration costs and the out of the world ins prices.

 

[Diesel JD]

I'd try to turn the engine over with a breaker bar and 15/16 inch deep well socket, if the engine turns over freely then good. I suggest you take the fuel shutoff solenoid lead off the injection pump terminal. If the thing turns over then you might try pull or roll starting it. Those batteries should be load tested before you call them good or bad. How about the starter itself, or how about the starter mount starter solenoid.

 

[Diesel JD]

Hmm Calvin beat me to it.

 

[boggerted]

I got it to run by pull starting it, i wanted to fix the starter issue. I yhink the stqrter mount solenoid is bad, can you replace that without the whole starter?

 

[towcat]

I got it to run by pull starting it, i wanted to fix the starter issue. I yhink the stqrter mount solenoid is bad, can you replace that without the whole starter?

yes you can.
i get mime from my favorite alt/gen/starter rebuild shop. cost? around $45 for a good quality new unit.

 

[EMD_DRIVER]

You can replace the solenoid mounted on the starter. Make sure you have a big phillips screwdriver, for the screws that hold it on.

I changed mine the other night, but the "New" one was bad. It took ripping the negative terminals off of the batteries, to get it to stop cranking.

My old one's plunger was spring loaded, to where it would stay out. Make sure the plunger on the new one is the same way. The plunger on the one I got from AZ was free moving.

Gary

 

[RLDSL]

I got it to run by pull starting it, i wanted to fix the starter issue. I yhink the stqrter mount solenoid is bad, can you replace that without the whole starter?

Yes you can replace just the solenoid .....but, buy the time the solenoid takes a powder on you, the starter usually isn't far behind and with a shiny new solenoid on it will leave you scratching your head with a no start problem from slow cranking speed not too far down the line. Unless the piggy bank is real tight right now, save yourself some grief and just replace the whole shootin' match while you have it out. For this very reason Bosch doesn't like to sell solenoids separately for a lot of their diesel starters.

You can pop a new Nippondenso starter in there for not a whole horrible lot more than the price of a solenoid and have that sucker spinning like crazy in no time.

 

[boggerted]

You can pop a new Nippondenso starter in there for not a whole horrible lot more than the price of a solenoid and have that sucker spinning like crazy in no time.

How much is that starter? Where can I find one? The only one I found is one that probably is garbage at autozone for $160.

 

[discbrks]

I bought mine from CarQuest for $130.00. It spins so fast that I think the truck is gonna flip over!

 

[Joe Mc]

I bought mine from Autozone and so far the lifetime warranty has been great. I have owned the truck 8 years and hope to keep it at least 30 years more.

 

[jrou111]

I had this problem this week too - all of a sudden it wouldn't turn over.

So I replaced the starter, and that wasn't it!

The batteries were fully charged, but I took them and got them tested, and they were only holding 650 cranking amps each! Apparently that wasn't enough to get the starter to spin. I bought two brand new 1000ca batteries and she fires right up with 1 GP cycle on cold 90% wmo!

$134.99 - starter
$198.00 - 2 batteries
Priceless - Firing up instantly on cold WMO!

 

[Diesel JD]

If you think that's bad, when I got my truck it came with two no name brand 350 CCA batteries. When I figured out how crappy that was I replaced them right away with 750 cca Interstate stuff.

 

[boggerted]

I tested the starter mount solenoid and its working. i also figured out that the truck will crank slowly if you tap the starter while turning the key. Does this mean the starters shot? Or could it be that its slightly siezed being that it sat for 4 years?

 

[towcat]

I tested the starter mount solenoid and its working. i also figured out that the truck will crank slowly if you tap the starter while turning the key. Does this mean the starters shot? Or could it be that its slightly siezed being that it sat for 4 years?

change the starter.
turning slowly after banging on it, tells me the armature has committed thermo nuclear meltdown.