HELP
Thread Starter
|
Freshman User
Joined: Aug 2012
Posts: 32
Likes: 0
HELP
I got a 1996 7.3 with 213k and i decided to put a new motor in it and its a 95 7.3 with 100k on it and its not sounding right and i cant really explain the sound it just doesnt sound right im putting a link to youtube to let you hear it see what you guys think i appreciate it guys you have been great help
Hotshot
Joined: Jan 2012
Posts: 11,132
Likes: 3
From: Southern West Virginia
If you have a ground issue, get that figured out first thing, and sounds like you have really weak batteries, or a bad starter. It should turn over way faster than that. The engine has to spin I think 100 rpm before it will start, but the ground problem could have the PCM messed up. Do you get a wait to start light when you turn the key on?
Post Fiend
Joined: Dec 2010
Posts: 10,121
Likes: 3
From: Orrville, Ohio
I agree with what Bill said. It doesn't sound like it is cranking fast enough. Either it is a power issue (which is where I would start if you're not getting power in the cab) or the starter is shot. Is that the same starter that was on the old engine (ie was it working before the swap)? Do you have any history on the engine that you swapped into the truck?
Thread Starter
|
Freshman User
Joined: Aug 2012
Posts: 32
Likes: 0
It was supposed to have had 100k and the trans went out on the truck and sat for about 8 months I've also heard it could be vapor locked? I have no idea. The starter that's on the truck now is the one off the old motor and its a good one I'm assuming that the batteries are just weak
Post Fiend
Joined: Dec 2010
Posts: 10,121
Likes: 3
From: Orrville, Ohio
Vapor lock...no, that's a gas engine problem. Lifters not pumping up no....not on these engines. Charge the batteries up and give it a shot then and see what it sounds like. And figure out why you don't have power to the cab. That could be a related issue to the engine not cranking and starting. If you don't have power to the cab, do you know for sure you're getting power to the PCM? Do you get a "Wait to Start" light when you turn the key on? Does the tachometer bounce when you're cranking it? I think you need to get the batteries on charge and figure out your power issue first, then worry about other things if it still won't start.
Hotshot
Joined: Oct 2003
Posts: 17,791
Likes: 98
From: Ashland City, TN
If you have a ground issue, get that figured out first thing, and sounds like you have really weak batteries, or a bad starter. It should turn over way faster than that. The engine has to spin I think 100 rpm before it will start, but the ground problem could have the PCM messed up. Do you get a wait to start light when you turn the key on?
<???>
Trending Topics
Post Fiend
Joined: Dec 2009
Posts: 15,505
Likes: 18
From: Livoina,La
Requirements to start a 7.3...............6.0
7.3L Powerstroke Starting Req.: *************************6.0L Powerstroke Starting Req.:
Vehicle Power : *10.5v ****************************************Vehicle Power : 10.5v
RPM Signal : 100rpm ******************************************RPM Signal : 100rpm
Inj. Cntrl Press. (ICP) : *0.85v (about 500psi) *****Inj. Cntrl Press. (ICP) : 0.85v (about 500psi)
Fuel Pulse Width : *1 to 6 milliseconds ***************Fuel Pulse Width : *0.5 to 2 milliseconds *
7.3L Powerstroke Starting Req.: *************************6.0L Powerstroke Starting Req.:
Vehicle Power : *10.5v ****************************************Vehicle Power : 10.5v
RPM Signal : 100rpm ******************************************RPM Signal : 100rpm
Inj. Cntrl Press. (ICP) : *0.85v (about 500psi) *****Inj. Cntrl Press. (ICP) : 0.85v (about 500psi)
Fuel Pulse Width : *1 to 6 milliseconds ***************Fuel Pulse Width : *0.5 to 2 milliseconds *
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Hotshot
Joined: Oct 2003
Posts: 17,791
Likes: 98
From: Ashland City, TN
Requirements to start a 7.3...............6.0
7.3L Powerstroke Starting Req.: *************************6.0L Powerstroke Starting Req.:
Vehicle Power : *10.5v ****************************************Vehicle Power : 10.5v
RPM Signal : 100rpm ******************************************RPM Signal : 100rpm
Inj. Cntrl Press. (ICP) : *0.85v (about 500psi) *****Inj. Cntrl Press. (ICP) : 0.85v (about 500psi)
Fuel Pulse Width : *1 to 6 milliseconds ***************Fuel Pulse Width : *0.5 to 2 milliseconds *
7.3L Powerstroke Starting Req.: *************************6.0L Powerstroke Starting Req.:
Vehicle Power : *10.5v ****************************************Vehicle Power : 10.5v
RPM Signal : 100rpm ******************************************RPM Signal : 100rpm
Inj. Cntrl Press. (ICP) : *0.85v (about 500psi) *****Inj. Cntrl Press. (ICP) : 0.85v (about 500psi)
Fuel Pulse Width : *1 to 6 milliseconds ***************Fuel Pulse Width : *0.5 to 2 milliseconds *
I thought I had read 400.
Post Fiend
Joined: Dec 2010
Posts: 10,121
Likes: 3
From: Orrville, Ohio
Talyn, I thought the number was 375 RPM so you're not the only one.
Have you charged the batteries? Check the voltage across the battery while you're cranking it. If it is lower than 10.5 volts, it won't start as the PCM doesn't have enough power to fire the injectors. I'm going to assume you're not getting any smoke out the tailpipe?
Have you charged the batteries? Check the voltage across the battery while you're cranking it. If it is lower than 10.5 volts, it won't start as the PCM doesn't have enough power to fire the injectors. I'm going to assume you're not getting any smoke out the tailpipe?
Post Fiend
Joined: Dec 2010
Posts: 10,121
Likes: 3
From: Orrville, Ohio
And the voltage? If the system voltage drops below 10.5 volts while you're cranking it you either need to jump it or charge the batteries. Below 10.5V system voltage (while cranking) and it WILL NOT start.