New engine - but is it getting fuel?

[NotEnoughTrucks]

Ray - I would like to revisit this post of yours.

On the dual tank trucks, there is a switch in with the heater controls, on single tank trucks, the switch is omitted, but the connector still exists near the heater control. There is a description of the 6 pin plug in the top corner of p.104 in the EVTM, but no references to connector number.

The plug that replaces the switch has two jumpers on it. There are two rows of 3 pins. The middle position will be jumpered to either the front or rear tank wiring. If the plug is missing, your in tank pump will not run and the fuel gauge will read empty. This is also a handy place to check for voltage to your in tank pump although it would not rule out a problem between the plug and the tank itself.

To begin - I am not certain if this truck started out as a single tank truck or dual. Close to the in-tank fuel pump connector is another connected set of wires (All taped up - possibly spliced) that run to the back of the truck. It runs to my tail lights/back up light. This is somewhat consistent with other wiring that is taped to the fuel pump wiring and runs to the tranny safety switch.

Second - The connector to the fuel pump has 4 wires: orange, pink/bk H, yellow/white stripe, and black (really faded) or brown. What is odd is that the connector wire colors exactly match the 7.5 single tank configuration as seen on page 102 of the EVTM. Not sure if this is significant but wanted to mention it.

Third - I also looked for the 6 pin plug you referenced. I found the plug mounted near the bottom of the right side of the heater controls. It is a grey plug with six terminals, but there are no jumpers on those terminals. Am I to do something with this plug, or just leave it alone?

Fourth - You mentioned that plug is a "handy place to check for voltage to your in tank pump". How would I do that?

Lastly - How could I bypass the pink/bl H wire temporarily to test if the the pump will work, and get some fuel in the line?

 

I'm going to go visit my old cab this weekend. Hopefully, I can get some pics of the area in question.

2 days of work came my way and our springtime weather is taking its sweet time in arriving this year.

[sgauvry]

I'm going to go visit my old cab this weekend. Hopefully, I can get some pics of the area in question.

2 days of work came my way and our springtime weather is taking its sweet time in arriving this year.

Yes. We have snow melting from a 10 inch drop we had last week. Supposed to be 52 today but nothing but rain between now and Saturday. Temps around 50 each day. Finally!

[sgauvry]

Thanks for your work, Ray! You too, Gary and Bill!

I pulled the tank pump just to give it a look-see (easily accessible due to my hatcbh built into the wooden bed). The pump is only a couple of years old. Couldn't see anything unusual there, but when I put it back in I no longer had a fuel gauge reading of full. In fact it read empty. That tells me the float was likely stuck in the full position.

I am befuddled by how the fuel gauge gave me accurate readings prior to pulling my old engine and now, zippo! :nabble_anim_confused:I know that tends to happen when one pulls things apart, but this really boggles me since I didn't mess with any of the wiring that leads to the tank. I think it is possible since there was fuel in the lines before I removed my old engine, the HP pump was working alone and the in-tank pump never worked except to give me an accurate fuel gauge reading.

I'm looking at page 104. That references a 2 tank system. I'm not seeing the switch you are referring to.

On page 103, the single tank setup, I see no switch there except for the inertia switch. I played with that a little but couldn't seem to get it to go anything. I was expecting to get kind of a reaction like you'd get on a GFI electrical switch.

Page 100 shows the fuel tank selector switch. Is that the 6 pin plug you are referring to? How the heck do you get to it. And, since my fuel gauge worked, could that selector switch be my problem?

Sorry for the long post. Just trying hard to figure this thing out.

Can't do any more today as my body is quitting on me. But I can read your reply when you have time.

Thanks a bunch!

Steve

Hey gents -

Few things to update -

Found what I think is the tank selector switch. Here are some pics:

There are only 5 poles to connect to inside the switch, but there are 7 wires coming to the back of the switch. 2 jumpers, possibly?

Here's the bad news: The ignition switch that is bolted to the steering column totally came apart. However, prior to doing so, I had a tremendous billow of smoke coming from the starter solenoid and voltage regulator area of the truck. Since the ignition switch started to come apart as I turned the ignition key to off, it would not stop the process of cooking components. Had to run over and disconnect the battery. The cooking of components meant that, even with the ignition switch replaced with a new one, I now have NO power coming to the dash cluster. That means no gauges, no wipers, no turn signals/flashers, no heater, no cranking, NADA! I do have headlamps and dome light. The engine will crank when jumping the solenoid.

All fuses are good. Is there a hidden fuse box I do not know about? Possible bad voltage regulator? Shot inertia switch? Ideas?

Thanks, gents! Can't move forward to this gets figured out.

 

[Gary Lewis]

Hey gents -

Few things to update -

Found what I think is the tank selector switch. Here are some pics:

There are only 5 poles to connect to inside the switch, but there are 7 wires coming to the back of the switch. 2 jumpers, possibly?

Here's the bad news: The ignition switch that is bolted to the steering column totally came apart. However, prior to doing so, I had a tremendous billow of smoke coming from the starter solenoid and voltage regulator area of the truck. Since the ignition switch started to come apart as I turned the ignition key to off, it would not stop the process of cooking components. Had to run over and disconnect the battery. The cooking of components meant that, even with the ignition switch replaced with a new one, I now have NO power coming to the dash cluster. That means no gauges, no wipers, no turn signals/flashers, no heater, no cranking, NADA! I do have headlamps and dome light. The engine will crank when jumping the solenoid.

All fuses are good. Is there a hidden fuse box I do not know about? Possible bad voltage regulator? Shot inertia switch? Ideas?

Thanks, gents! Can't move forward to this gets figured out.

Ouch! That's gonna be a problem.

First, you will need to acquaint yourself with this section of the EVTM: Electrical/EVTM/1986 EVTM/Charge & Power Distribution. There you'll see several fuse links, one or more of which is probably fried.

You can usually tell a fried fuse link because when you pull on it the wire is gone inside and the insulation will stretch. Fuse Link L feeds the headlights so it must be good. But Fuse Link M feeds the ignition switch and that is the likely culprit.

[sgauvry]

Ouch! That's gonna be a problem.

First, you will need to acquaint yourself with this section of the EVTM: Electrical/EVTM/1986 EVTM/Charge & Power Distribution. There you'll see several fuse links, one or more of which is probably fried.

You can usually tell a fried fuse link because when you pull on it the wire is gone inside and the insulation will stretch. Fuse Link L feeds the headlights so it must be good. But Fuse Link M feeds the ignition switch and that is the likely culprit.

Hi Gary -

Yes. I have been looking at that. Not seeing a fuse link M.

Page 15, 16 - (With Alternator Warning Indicator) Gasoline (without auxiliary battery)

Fuse links I, H, G, F, E, N, S, D, B, C, P. There is no Fuse Link M.

Fuse link E, possibly?

Will also tell you I checked voltage downstream of each fuse link. 12.4 volts on all readings.

Thanks!!

Steve

[Gary Lewis]

Hi Gary -

Yes. I have been looking at that. Not seeing a fuse link M.

Page 15, 16 - (With Alternator Warning Indicator) Gasoline (without auxiliary battery)

Fuse links I, H, G, F, E, N, S, D, B, C, P. There is no Fuse Link M.

Fuse link E, possibly?

Will also tell you I checked voltage downstream of each fuse link. 12.4 volts on all readings.

Thanks!!

Steve

Look at Page 20 Figure 1. Granted that's for the diesel, but I'm pretty sure that M was in the same place for a diesel as a gasser.

[sgauvry]

Look at Page 20 Figure 1. Granted that's for the diesel, but I'm pretty sure that M was in the same place for a diesel as a gasser.

The pic on page 20 is for an aux battery and M is for a system with an ammeter. On that page, fuse G is for the alternator warning indicator, but also for a system with an auxiliary battery. Or am I reading this wrong?

Back to pages 15 - 16, Fuse link H runs to the ignition switch, wire 37 yellow. Will also check Fuse link E wire 38, bk/o runs to fuse box.

Sound like a plan, man?

[Gary Lewis]

The pic on page 20 is for an aux battery and M is for a system with an ammeter. On that page, fuse G is for the alternator warning indicator, but also for a system with an auxiliary battery. Or am I reading this wrong?

Back to pages 15 - 16, Fuse link H runs to the ignition switch, wire 37 yellow. Will also check Fuse link E wire 38, bk/o runs to fuse box.

Sound like a plan, man?

Fig 1 on Page 20 is looking at the passenger's side fender, and is not for an aux battery, which would be on the driver's side. And, Fuse Link M is for all vehicles in 1986 as they appear to have included an ammeter on all of them.

For 1985 the EVTM shows that it is called Fuse Link I for vehicles that have a warning light. But it is the same circuit #37 with an orange 16 gauge link (the 1986 is a green 14 gauge) that goes from the starter relay back to the yellow wire going to the ignition switch.

[sgauvry]

Fig 1 on Page 20 is looking at the passenger's side fender, and is not for an aux battery, which would be on the driver's side. And, Fuse Link M is for all vehicles in 1986 as they appear to have included an ammeter on all of them.

For 1985 the EVTM shows that it is called Fuse Link I for vehicles that have a warning light. But it is the same circuit #37 with an orange 16 gauge link (the 1986 is a green 14 gauge) that goes from the starter relay back to the yellow wire going to the ignition switch.

Yep! Fuse Link I is the one!! Will check that next chance I get. But if it's sending through 12.4 volts downstream of the fuse link, it is ok, right?

Thanks!!

[Gary Lewis]

Yep! Fuse Link I is the one!! Will check that next chance I get. But if it's sending through 12.4 volts downstream of the fuse link, it is ok, right?

Thanks!!

Yes, if you have voltage downstream then it must be good. But remember to fix whatever shorted before you replace the fuse link. You can buy fuse wire at many parts stores.