Hey guys,

Another one of my truck from hell threads

So my truck keeps draining my two batteries (diesel). I will go to start it and It will turn over good for a few seconds.

I believe there are two reasons possibly,

(1) I need to spray my air box with starter fluid before I start it if it isn't still hot, so if I don't I probably drain the batterys.

(2) the PO wired it so that the engine with crank on a switch rather than through the ignition.

So I have to turn the ignition switch to on, and then flip the switch to get it to turn over.

So my scenarios is, I run it say for awhile and park it for a few hours, and I want to try it again with out the starter fluid, I give it a try by turning the ignition, and flipping the switch, I don't get anything, turn the switch back off and LEAVE THE IGNITION engaged, get out of the truck and spray it with fluid, get back in and flip my starter switch again, and at that point, I know longer have enough juice for it to really crank over, it is too slow.

My thought is that, I need to turn the ignition back, because it is draining the battery to quickly, does that make sense or should the ignition being turned to on not drain the battery that quickly.

So my fix I would like to do, is wire the starter back into the ignition switch.

And also fix the starting with the fluid issue.

Thanks Guys,
Devin

 

Your batteries are probably no good. If you put them on a trickle charger overnight, in the morning it should whip that engine over very quickly. And you should be able to do this several times before it slows. If the batteries are good, they normally will burn out the starter before they give out.

Now about all this wiring; Are you using the glowplug system? If you are, how is that wired in? The only suggestion I have for you as far as the wiring is to drop the column down and look at the ignition switch, and see if the wiring has been modified there.

 

You shouldnt use starter fluid unless your glowplugs are disabled. You can do serious damage.

The starter circuit being on a different switch should not cause your batteries to go dead. Have you checked it for a draw? Disconnect both battery negative cables, then put a test light in series with one battery to the cable you disconnected. If it lights up any more than really dim, you have a draw. It sounds more like you have a bad battery. Have you had them tested?

 

No, they are brand new batteries

I was thinking I was draining the battery while my ignition was turned to on, but I don't think so now that I think about it.

Yes I am using glow plugs.

Now to drop the column down and to mess with the ignition, don't I need a tool to push the steering column back in or something, Someone told me this because I also have no key, I can just turn the ignition freely and I need to get a new ignition and key from a junker.

Why shouldn't I use starter fluid? and no my glow plugs aren't disabled, I wouldn't know how to disable them anyway, cause don't I need them to get the engine started.

I guess the other important question is why do I need starter fluid?

 

IF your new batteries are good and big enough to start this thing, you probably have a bad starter, cables, or a bad connection. You should be able to keep cranking until the starter burns up before it slows down.

Starting fluid causes very high pressure in the combustion chamber. It burns better than diesel fuel. You can blow a head gasket or blow a pre-cup out of the head. That loud rattling you hear when it first starts with SF= BAD.

 

I don't think the starters bad, because it acts like a draining battery, I am going to try it again later when the engine is cold and see how long it cranks for and I will report back.

 

Cold start the 7.3L IDI with bad glow plugs - YouTube
Heres a video that will give you an idea of how fast it should be cranking.

 

That's what mine sounds like, but I do not get that long out of it.

So I think my problem is definitely with the batteries losing a charge.

But could It be possible that I could not be turning over because maybe all of my glow plugs aren't working, the PO did a really hack job on the wiring for the glow plugs, so its possible that's why its not firing right up?

 

Without knowing what the Previous owner did to the wiring, there could be a lot of faults that could drain the battery.

Both batteries on a Factory dual battery system is supposed to be isolated when the truck is off, and only connected to the alternator when the ignition switch is turned to run with both batteries charging with the engine running. Have no idea if it's still hooked up that way or not.

If it was miswired when they bypassed the ignition switch, your glow plugs may not be getting any power. Could be one of your problems. Cannot tell untill you go and inspect the wiring unfortunately.

The ignition switch is a multi throw switch and switches several different circuts at once. If it's been bypassed through a single throw switch, that could be part of your problems.

Sounds like the truck needs a total rewire or wiring rebuild. I would seriously suggest removing all the wiring and fixing it on a workbench like I described in the other thread. That would take all the guesswork out of the wiring, as you would know it was 100% after the rebuild.

 

Yeah I am starting to consider that some more, I think I am going to go to the junk yard again tomorrow and see if I can cut a few pieces of wiring harness out, my understanding is that is is set up in chunks so If I can get full pieces I will.

If not I will be hacking away and mending back together in mine.

Thanks

 

Yes, there are several different seperable sections of harness that can be replaced in "Chunks".

The largest section is the main harness which consists the fuse panel, instrument cluster, Radio, headlamp, wipers, heater, and ignition switch wiring. All other harnesses plug into the main harness in some way. Some of the different harnesses are as follows...

Engine harness

Framerail harness.

Alternator harness.

Rear Taillight/Brakelight harness

Then you have optional accessory harnesses.

Dual Battery Harness (If Equipped)

Trailer Wiring Harness (If Equipped)

Cargo / Map / Dome lamp harness, (if Equipped)

Courtesy Light harness (if Equipped)

Radio speaker harness (If Equipped)

Cruise Control harness (If Equipped)

Clock Harness (if Equipped)

Fog Lamp Harness (If Equipped)

Power window/door lock harness if equipped. (These plug direct into the fuse panel so it's not obvious it's seperate)

Then you have short pigtail harnesses for...

Underhood Lamp
Underdash Courtesy / glove box lights
Cab Marker Lights

etc...

Try to get close to the same year model as what you have for best compatibility. Ford had a habit of changing connectors between the years that make wiring swaps more difficult. Match the connectors and you should be good. 1984-1986 would be the most compatible, with 1985 being the best match.

Also keep in mind the wheelbase issues with a crewcab and the framerail harness. The framerail harness will be longer with the crewcab than say the regular cabs. Diesel engine harnesses are different than non-diesel. The main harness is different with diesel, and between instrument clusters with gauges vs instrument clusters with idiot lamps. The alternator harness is different depending on amperage, and if the truck has a ammeter or warning lamp etc... Just be aware of those differences as well. If the harness doesn't quite match then it could be one of these reasons, and therfore it's not compatible. They will usually have different connectors to keep you from mismatching and using them etc...

As for wire repair...

Wires can sometimes be replaced one at a time by removing the terminals from the connectors and transplanting the whole wires between two connectors. Mostly this can be done with with Ford's plastic connectors. They can be removed with a wire removal tool, or with a precision screwdriver as the wire and terminal is locked into the connector by a small plastic tang. Some connectors have a red or brown lock inside the connector that locks the wires inside. This will have to be removed before you can remove the terminals. The terminals that go inside the connectors are still avaliable. This way you can crimp them on new wire sections and reuse the factory connectors without splicing. This is very easy when you remove the harness and remove the protective tape from the wires as I explained earlier in your other thread.

Most Ford weather tight connectors of this time frame are not repairable and need to be replaced by cutting and splicing or in whole wire groups. You should be able to tell the two types of connectors apart.

If done rightly you can rebuild these harnesses and make them look and function like brand new, and would not be able to tell the difference from factory original. It can be time consuming, but I think it's well worth the effort. Especially if you plan to keep the truck for a long time.

Hope this helps...

 

Hey, Devin,

You are new here, and I know that it can be real hard to know who knows what they're talking about when you come to forums like this.

That's why I'm saying... you have some of this forum's - and the industry's - best guys here trying to help you, please listen to them. None of them can truly diagnose your truck without seeing it, we all have to rely on information you provide. But all three of them are spot-on with their initial diagnosis - based on what you've told us.

With that being said, I agree with them... if the batteries are in good working order (which "new" would imply but not guarantee) then the problem is most likely between the batteries and the starter... could be corroded cables and/or connections (including the negative between battery and block), a starter solenoid at the end of its useful life, or the starter motor could be burning out and drawing more current as it heats up.

There are other things it could be, too, but none of us have seen your truck and so certain assumptions are made that everything else is in good working order. Without having seen it - or read descriptions from you - it's impossible to know by remote.

I would begin with investigating the fat cables between the battery and starter, and maybe remove the starter and bring it to a parts store for testing on their machine. Or, maybe bring it to Sears or Pep Boys or some such and ask them to do a starter draw test, this is often done for free as a courtesy. (I don't necessarily trust counter clerks at parts stores to know what they're doing so I won't recommend going there, but a parts store can sometimes do this, too.)

It seems you now own a truck with a lot of problems and a lot of hacks done by POs. This will take you some time to get straightened out but the guys here can help you if you let them.

 

Is this your first diesel? I can tell you right now, if your glowplugs are not being used/not working(I don't see how they could if the ignition switch is not hooked up correctly) this engine will never start.

A diesel has no sparkplugs to ignite the fuel. The fuel ignites from the heat of compressing the air on top of the piston. When the engine is cold, there is no way to generate enough heat for it to fire, the cold engine metal sucks all the heat away. So you have to have a starting aid to add heat, or it will never fire off. Starting aids that add enough heat are;

Working glowplugs.

Plugging the block heater into a 110v outlet

Starting fluid used in moderation, with the glowplugs disconnected.

Once you get it running and fully warmed up, on a warm day you will not need any starting aids usually the rest of the day. You've got to have something on the first start of the day though, no matter how hot it is outside.

 

Thanks guys for all the useful information,

I pulled some chunks of harness from the junkyard today, it is seeming to integrate it back in is more difficult than I thought, it is also about 30 here in Vermont and I only brought two pairs of clothes and neither are really for cold weather, so I can only stay out 10 minutes at a time and then start to get too cold again, and that is really not enough time to get any good work done on the wiring... I need a garage lol.

Anyway I am going to try again in the morning.

I also noticed and suspected before, I don't have a starter relay It looks like. I pulled one from the yard today and am going to try add it back in with the wiring but we will see how that goes.

Also, I notice I have this:




And I am not sure what it is, I did not see it on the vehicle I pulled from, but it also makes it more confusing for trying to fit the new wiring in.

 

I would expect that NAPA box to have identifying numbers on it someplace (maybe on the bottom).