99 7.3 will not turn over

[jc1187]

Hello all,

I have visited the site numerous times in the past. Lots of great info. This is my first and hope someone can give me some valuable info. First off I'm not very familiar with regards to diagnosing/repairing mechanical and/or electrical issues, so be patient with me. I know enough to get me in trouble.

I have a 99 7.3 6speed with 180k. cam positioning sensor has been replaced. The plastic clutch safety switch located on the push rod busted a couple of months ago, but i rigged it with some tape and basically it hasn't given me to many problems. Occasionally the truck won't turn over so i reach under the dash and reposition the switch and all is good.

Yesterday I climbed under the hood to replace the fuel filter. After replacement I attempted to start truck and just got a clicking sound. Engine would not turn over. I decided the clutch safety switch had finally given up so I purchased a new one and installed it. This didn't help anything. Thinking the switch may be defective I removed it from the from the clutch push rod and manually slid the contacts forward while my son tried to start the truck. Still nothing. I did notice that when the key is turned to the starting position, when I slide the clutch safety switch forward it causes the clicking sound which makes me think the switch is working as it should and that there is another issue. Any suggestions are greatly appreciated

[JSchuricht]

Check the relay on the passenger fender. You can try jumping it with a screwdriver, turn the key to the run position and make sure the truck is out of gear first.

[zambonimaxx]

Not trying to belittle your knowledge...but did you check the batteries? Is the clicking coming down from the engine bay or inside the cab? Do you hear the fuel pump kicking on when you put it in Run? WTS light light up? The temperature change is starting to take affect and the first place you will see it on these trucks in in the battery life. I had to replace 2 Optima Red-Tops within 2 years since the weather is so drastically different in 29 from summer to winter.
~Phil

[Degnol]

Originally Posted by zambonimaxx

Not trying to belittle your knowledge...but did you check the batteries? Is the clicking coming down from the engine bay or inside the cab? Do you hear the fuel pump kicking on when you put it in Run? WTS light light up? The temperature change is starting to take affect and the first place you will see it on these trucks in in the battery life. I had to replace 2 Optima Red-Tops within 2 years since the weather is so drastically different in 29 from summer to winter.
~Phil

^^^^^^^^^^^^
THIS

[ToMang07]

99 7.3 won't crank

[jc1187]

Phil,
Batteries are good. Clicking noise appears to be a relay switch under the hood on the passenger side. I looked it up on auto zone web site. I think it's the glow plug relay. When I have my son turn the key that relay makes a loud clicking noise. The WTS light is working properly. Thanks for any info.

Jeff

[jc1187]

Hi,

The relay under hood on pass side you mentioned is where the clicking noise is coming from when I turn the key to attempt to start the engine. Sorry but I don't understand how to go about jumping the relay with a screwdriver. Can you explain with more detail for me.

Jeff

[redneckabbott]

Same problem! Batteries are good and replaced safety switch. Will turn over by jumping the solenoid.

[timmyboy76]

check the #30 30amp fuse. if popped, unplug the fuel bowl heater, and see what happens

[redneckabbott]

Fuel bowl heater was unplugged long ago. Decided to swap my relays around and that solved most of my issue. It still won't start from the switch. Had to jump the starter relay. I hands a cousin with a parts truck so maybe I can try some parts and get this figured out.