White-GMC 94’ STC 330 N14

[Spud_Monkey]

Yep I went and got the truck, just never made it home with it “yet” asking was $6500 got it for $5250, 313k miles and I will update more specs later with pictures. Anywho about that “yet” part I’m sitting here in it about 300 miles from home off exit 200 in North Dakota after it decided after 175 miles to lose power. Started down to 55 mph and after all is said it crawled in at 5 mph, so I guess I get iron problems out on the road at midnight. Opened up water drain valve it spit some out looked like turpentine, blew the main hoses to backwards into tanks no problem, blew into PT pump it shot out fuel but still not getting up to any power. The fuel filter was dry when I opened the drain cock before starting anything and I can’t take it off just yet. So my theory is fuel filter is plugged, next one is air getting sucked in fuel lines that can’t be seen and last one is plastic wheel in the PT fuel pump is worn down. Did I miss anything? As I sit here the rig idles fine just rare lowering of RPM. Also I put some Lucas fuel treatment in and filled the tanks three quarters ways.

 

[funwithfuel]

If the filter is dry, odds are you sucked air. Loose fittings dry rot aeroquip hoses ,that sorta thing. When you blew back towards the tank, did you hear bubbles? How many inches of fuel you got in them tanks, and are they equal?

 

[Truck Shop]

How much fuel is coming out of the return line? Should have a good steady flow. Photo of fuel pump please to make sure it's a mechanical N14. Any back pressure or poor flow on rerturn line can cause aneroid on
pump to cut fuel back, if it truly is a mechanical PT pump, even with STC.

 

[funwithfuel]

How much fuel is coming out of the return line? Should have a good steady flow. Photo of fuel pump please to make sure it's a mechanical N14.

Did they make a celect with STC?
That'd be cool if someone swapped in a 400ESP+

 

[Truck Shop]

The early N14 mechanical late 92 to early 94 were STC with a PT pump. Next thing to do is pull both fuel hoses off and bypass every thing by running it out of a bucket. But I would chance the filter at the pump
is plugged full of algae crap possibly from setting or it had Bio fuel in it just setting.

 

[Spud_Monkey]

Got to bed around 0100 hrs woke up around 3 when it decided to shut off from idling, cranks back up but dies in few minutes. Going to get a fuel filter while waiting for it to warm up to dig in. Not going to be easy at a truck stop doing this, was in the 20’s last night with no heat.

 

[Spud_Monkey]

If the filter is dry, odds are you sucked air. Loose fittings dry rot aeroquip hoses ,that sorta thing. When you blew back towards the tank, did you hear bubbles? How many inches of fuel you got in them tanks, and are they equal?

Yep they are close equal at about 50 gallons full and I heard bubbles in the closes tank when I blew it backwards.

 

[funwithfuel]

You've got an obstruction somewhere. Standpipe is probably getting jammed up either on the bottom or up at the first elbow under cab. That knurled cap on the back of the fuel pump, try and tighten that by hand as much as possible. That's where the fuel filter would've originally been. That's just a bypass now and could be sucking air, it is fuel stained, so I'd start there.

 

[Spud_Monkey]

You've got an obstruction somewhere. Standpipe is probably getting jammed up either on the bottom or up at the first elbow under cab. That knurled cap on the back of the fuel pump, try and tighten that by hand as much as possible. That's where the fuel filter would've originally been. That's just a bypass now and could be sucking air, it is fuel stained, so I'd start there.

Well I took it off when I blew backwards from the filter housing to the pump line to see if it would fix it. Though will tighten it more if possible. Got filter from Napa going to put it one if no go going to take all lines off and blow through and if still no go, going to get new fuel lines.

 

[Spud_Monkey]

Yummy, might need two filters or three time I’m done.

 

[funwithfuel]

Oh man that's some nasty rust ya got there.
Steel tanks?

 

[Spud_Monkey]

Oh man that's some nasty rust ya got there.
Steel tanks?

Nope, aluminum ones.

 

[Truck Shop]

Shine a light down in the fuel tanks and see if you can see the bottom and how much scum is in the
very bottom. It looks like the STC control box is just below the PT pump, follow the fuel from the box
to the pump, remove that line and see if there is engine oil in that hose a #4 fitting. The STC is controlled
by engine oil pressure in that box, there should be no engine oil in that fuel line. That could be why the
fuel is dark.

 

[Spud_Monkey]

I will do that if I can get this thing home. It’s purring like a kitten, drove 100 miles stopped for fuel for the car and now it’s overheating even though it has plenty of fluid. Guess the fan clutch is bad too or slipping on the belt. So I’m sitting here on side of road letting it cool down, what joys of fun. Two hundred fifty miles to go...

 

[funwithfuel]

What kinda clutch kysor, Horton's? There's ways of mechanically locking them.

 

[Truck Shop]

Could also have a viscous fan hub or the type with the air line entering the front of the hub, Kysor.
Horton uses two socket head coarse 3/8 x 1 1/2 bolts in the center of the front of the fan hub to lock it.
Probably the Stat is sticking, best guess. Because bobtail it shouldn't need the fan.

 

[doublewide]

We're rootin' for ya spud!

 

[Truck Shop]

If you need I have a N14 manual I can loan you.

 

[Spud_Monkey]

What kinda clutch kysor, Horton's? There's ways of mechanically locking them.

Don't know yet, I will find out tomorrow, I'm tuckered out.

Could also have a viscous fan hub or the type with the air line entering the front of the hub, Kysor.
Horton uses two socket head coarse 3/8 x 1 1/2 bolts in the center of the front of the fan hub to lock it.
Probably the Stat is sticking, best guess. Because bobtail it shouldn't need the fan.

It shouldn't be hitting 210 either or running at 190 then creeping up to 200 on climbs either. I heard the fan kick on it's quiet with windows up, 30 mph head wind and climbing hills doing 1700 RPM around 65 mph, though when I hit the dirt road I could hear kick on around 210/220.

If you need I have a N14 manual I can loan you.

I got one from Manual Lib for free it was 587 pages labeled Shop Manual, though thanks for the offer

We're rootin' for ya spud!

I made it home!!! I think I slept about 4 hours in past 48 hours, but I made it, hell or high water, true grit here. Anywho thanks for the support guys as I cut, snip, tweak and fix things I will update on here. Pictures will come tomorrow in mean time it's time for some 130 proof bourbon so I can sleep tonight.

 

[Spud_Monkey]

We got a 2 line wet line kit on here, hmm what are all possibilities I could do with this...