Hello All,

New to the forum here and also new to the diesel world. I've spent plenty of time doing work on gas engines but this is my first diesel.

I just bought a '92 F250 with a 7.3 and I've got plenty of questions! The truck is an XLT, automatic and has 318,000 miles on it.

When I went yesterday to get the truck, I replaced the starter as it was bad. We tried starting the truck with the new starter and had no luck. Next, we hooked the truck up to jumper cables as I had a feeling the batteries were to weak to engage the starter enough to turn the flywheel. Sure enough, the starter was able to turn the flywheel and the engine began to turn over. After a few tries, the engine still wouldn't start and I didn't want to ruin a new starter so we decided to use some starter fluid to see if it would fire up. One quick, small spray and she fired right up. Bingo!

I left the truck running while getting ready to leave and then drove it about 20 miles home. The truck ran great and I had no issues once the truck was running.

After getting home, I killed the engine and decided to try and start the truck again to see if it would crank up. No dice. At this point, it was late in the day so I decided to leave her be until morning. This morning, I pulled the batteries and took them to get tested and they were both shot. Would not hold a charge which is what I suspected being as they were cheap batteries from Wal-Mart and were three years old. Purchased new batteries and got them under the hood and hooked up.

Once the new batteries were hooked up, I instantly noticed how much stronger the starter sounded and also noticed that the lights and everything in the dash was working much better. So, that piece of the puzzle was solved but the question of whether or not it would start was still unanswered. After a few tries of starting the truck, it still wouldn't fire up so I left it be for the time being...again, don't want to ruin the new starter.

All of this brings me to my next question. I picked up new glow plugs (yes, the MotorCrafts) as the previous owner said the ones in the truck are probably burned out. I'm hoping this will fix my problem and I will find out this week sometime when I get a chance to change them out.

The wait to start light is not in the dash for whatever reason. However, when I turn the key to on position, I get the clicks. I'm waiting for the clicks to stop before trying to start the engine but all it does is turn over and never fires up. Do I need to diagnose maybe another issue (GPR) before replacing the glow plugs or should I just go ahead and replace them and see if that works? I do know the ones that are in it now are the AutoLites so I'm hoping I don't run into any problems getting them out.

Lastly, this truck sat for two months and it's obviously an old truck with high mileage. What else should I look for/do as far as maintenance to ensure it runs decent and fires up with ease? This truck will live at the deer lease for a few months during the season so I'm wanting to get it in good working order before taking it out there.

Phew, sorry for the long winded post but like I said, I'm new to diesels. Any and all help/advice will be much appreciated and I can't wait to get my hands dirty and dig into this project of a truck!

 

Unless all 8 glow plugs are in good working order, connected, etc. the GP system won't work right. This will produce fast clicking and no actual heating.

Before you can really do troubleshooting you have to replace the GPs, or make sure that all 8 work(test with a wire to battery +, if it sparks touching the top of the GP the GP is good).

In the mean time... keep a container of starting fluid handy. Just need to make sure that the GPs are not hot when you spray ether.

As far as maintenance, make sure you've got clean oil in it, and SCAs in the antifreeze, keep a spare jug of oil in the truck(It'll probably leak/burn a significant amount).
You may also want to look at replacing the return lines and return O-rings, but if it will fire off with a little bit of ether on the first try, that's not a problem now.

 

That's what I figured with my limited research on these forums. I will replace all GPs and see what happens. If still having trouble I will move on to the next piece of the puzzle. I definitely plan to keep some oil in the truck at all times just in case. The PO said it was using about a quart of oil between changes so we'll see how accurate that is. There is a small leak on the right side valve cover so I plan to replace that gasket and help slow some of the loss.

Thanks for the reply and helpful information.

 

If that's true, that's great. Before I rebuilt my motor, it was using about a quart every 500 miles.
The good news is you can run these engines 2 quarts low before you even hit the add mark, and there's enough reserve capacity that you can actually be about a gallon low without losing pressure. Not that I'd ever /want/ to be that low...

Oh, one other helpful tip -- when replacing the oil filter, use an oil filter from a 7.3 Powerstroke engine. It's a longer filter(More media = better filter) that's the same diameter and threading, and fits easily enough. It also adds an extra quart of capacity.
It's also very easy to find anywhere due to how common those engines are.

 

So I finally got some time this morning to get the old glow plugs out and replaced with Motorcrafts. That was definitely one of my problems. The old were all burned up. Once I got them all replaced, I turned the key to on and instead of the constant clicking that I was getting before, I got one click and then could hear it cycle. Once it cycled off, I tried to start the truck but could tell the power was weak. Hooked it up to jumper cables and it fired right up.

Took the truck for about a 10 minute drive and then once I got back to the house, I attempted to fire it up two more times with no problems and then I could not get it to fire up unless hooked up to jumper cables.

Now I'm thinking it's the alternator which wouldn't surprise me but I also think it might be my battery cable terminals. They are pretty beat up and it's hard to get them on tight to have a solid connection. Is it possible that with a bad connection on the terminals the alternator is not able to do it's job of charging the batteries? I'm thinking I should replace the terminals first and see if that fixes my issue before spending $150 on a new alternator.

If not, they need replacing anyways so I think it's worth a shot to see if that fixes my issue.

Thoughts?

 

Before doing wiring stuff, get yourself a digital multimeter. $5-20, depending on where you get it.
You /need/ one. That will tell you if you're charging, or not, or what. You can then test your regulator, alternator etc.

First step is getting a multimeter.

 

Sounds like youve got a buncha little problems, but youre getting em sorted out. Welcome to the board.

x2 digital multimeter is pretty handy, even if it is the $2 harbor freight one.

 

Ok. I'll pick up a multimeter today and see what I find out.

Also, I noticed yesterday while driving the truck around that the transmission is shifting hard through 1st and 2nd gear. Any clues to why that's happening?

I also found this on the passenger side behind the battery. Does anyone know what these wires are?

 

also get a small battery charger and leave it on low charge overnight.
it takes a while to charge the batteries. 10 minutes of driving after a start is not enough to do anything.

what type trans is in it, a C-6(3 speed auto) or an E4OD(overdrive trans)?
if it has the E4OD trans, the shift solenoids in the trans tend to "stick" after sitting causing harsh or late shifts.

 

Picked up a multimeter and tested the load on the batteries before starting the truck and also after it was running.

I got anywhere from 12 to 12.26 volts without the truck running and about the same or slightly less with the truck running. So it appears that the alternator is not working. Anything else to check before replacing the alternator?

 

check the stud on the back of the alternator.
and hook those wires that are cut back up, if i remember correctly you have a voltage regulator on the passenger side fender. if the wires to the regulator are cut, the alternator will not charge the batteries.

 

I'll get those wires repaired and connected and that should probably fix the problem...or at least part of it. I didn't realize until just a bit ago when I started tracing the wires that those are the ones coming off of the alternator that tie into the battery cables!

Also, this is on the other end of the wire harness that connects to the alternator. Can someone point me in the direction of what this is supposed to plug in to?

 

looks to me like AC compressor

 

Yeah, that dawned on me this morning. PO took the compressor out and I realized that's where it goes.

Any suggestions on best way to fix the cut wires? I was thinking butt splice if I have enough wire on the plug end.

 

butt splice will work for a while, but eventually they will corrode and fail. i prefer soldering the connections, then sealing them with heat shrink tubing, then finish it off with a coating of 3M black electrical tape.