The Oh Fishall Fuel Pump Thread

[12V71]

Sam, did you check fuel pressure? I've had Chevy pumps with worn impellers scream like a banshee and not put out any pressure. A pump with a good impeller may sound slower.

[farmersammm]

Sam, did you check fuel pressure? I've had Chevy pumps with worn impellers scream like a banshee and not put out any pressure. A pump with a good impeller may sound slower.

I think I'm good now.

I took the thing back to Oreilly, and we tested it side by side with another one off the shelf. The pump has a nice super high pitched sound, but very quiet. It matches the other one in the back tank sound wise, so I'm golden!!!!!!!!!!!!!!! It sucks that out of 2 brand new pumps, one was defective. BUT THEY WERE VERY NICE ABOUT EXCHANGING IT. We had almost the same problem with a starter for K'kins car..........it took 2 to get a good one.

Fuel pressure is running 35 at idle (also key on engine off), and upwards of 45 at snap. The biggest change has been the idle after snapping the throttle.

Before replacing the pump, the engine would sputter, and lose rpm after a throttle snap........then regain rpm. Now, there's no hesitation at snap, and no stumble at idle after the snap.

I've only put fuel in the front tank. I'm waiting for Monday to call the dealer, and try to get ahold of the fuel vapor valve seal before I put any gas in the back tank. They have 2 different valves on these...............one is a single line valve, and this truck has the 2 line valves. The seals are different for each type of valve. I've seen the correct seals on Ebay, but they're days a way. I'm hoping the dealer has them in stock.

After startup, I cleared the fuel in the rail by releasing pressure from the fuel pressure tester. I got a bit of yellow gas, but only a bit. It's running a nice bluish color now. I'm thinking that the yellow stuff was already in the rail before I replaced the pumps. This truck has had a bad history of water in the gas.

To be safe, I also cleaned the front tank best as I could without removing it. It wouldn't have made any difference anyway...........it's a long tank,, and I can't reach all the way to the ends through the fuel pump hole, so it couldn't have been manually scrubbed any better off the truck.

The gas that came out of the tank when it was siphoned was yellowish tinted. The walls of the tank, when scrubbed, also had yellowish crap on them. This is probably residue from the many times the tank has been waterlogged. While scrubbing, I did find some pretty bad rust on the low spot in the tank (front tank is metal, not plastic like rear tank). I checked, and these tanks are still widely available, so I'm not too worried. Probably get one, and put it up for when this one starts to pinhole.

When it died the second time, after replacing the filter, I replaced the filter with what they had at Oreilly. I believe it's a Wix, or some other brand. Anyways...this was when I figured I needed a new pump......the filter wasn't clogged.

I had a Fram in it before I replaced it. Brand new one. When I pulled it off, it was actually easier to blow through than the new Oreilly filter. I plan on picking up a few Fram filters, and pulling the Oreilly filter immediately. Then change filters a few times till I'm sure all the loose stuff is out of the tanks. I know there has to be some stuff left in them, if only lint from the rags. Sometimes the aftermarket filters are too tight micron wise. They brag on how fine the elements are. IMHO, all this does is place load on the pump. Fram is about as close to OEM as you can get. BTW.........they do the same with furnace filters for the house. The fine media Heppa filters make your blower work like a mule. I refuse to use them. I go with a standard fiberglass filter when I can find them. They're getting rare though.

Until the back tank is fully flushed, I'm gonna keep spare filters, disconnect tools, and a pressure gauge(to relieve rail pressure, inertia switch is almost impossible to get to), in the truck. I'm sure there's some sludge I missed. Be a fool not to plan on maybe having to replace a filter somewhere on the road.

Hopefully start on the bed tomorrow. Shim modifications, and dealing with the water in the gas problem. The stupid thing has trapdoor filler pockets on top of the stinkin' bed. Stupid.......they fill up with water because the drain's too small, and hay/dirt gets in there and plugs them up. Never fails.......I usually clean then out,, but the one time it rains hard is the time I forget to clean them. Gonna get rid of that problem first thing.

[farmersammm]

I Just Had To See

Remember how you were when you were a kid. Just had to poke around in something to see how it worked. Had to tear it apart. (Fixing came later, ruining was easier)

I think I now know why the back tank never worked since I bought the truck The fuel system, with the way the flatbed is designed, is about the most vulnerable thing on this truck, and probably always has been, since the bed was mounted a quarter century ago. Bed's been on that truck longer than some folks have been alive

[12V71]

That's the inner kid in us that takes stuff apart to see how it works.

[M J D]

That's the inner kid in us that takes stuff apart to see how it works.

Or in some cases certain groups do that to entire nation.

[farmersammm]

Got my seals in today, so the rear tank is ready for fuel...........sorta.

I still need to repair the filler hose.

I called a guy I do business with regularly, and he has two grades of filler hose. One stiff grade, and another more flexible grade. The flexible grade runs around $9/foot. I didn't ask what the stiffer grade runs.........but it's probably like the tank truck hose I buy from him for the swather. It's about twice that price.

Total out the door price for the hose, union, and t-bolt clamps, is around $30. That is GREAT!!!!!! To buy the same crap through Oreilly would be about 3x that price.

AND I GET TO STOP AND GET TAKEOUT FROM CARL'S JUNIOR

We ate our first takeout in a year this week. Both our vaccines are in full effect now. It was a pleasure to bring home a bucket of chicken from KFC. Funny thing we both looked at each other, and said "Well that's enough KFC for the next 6 months". You might miss stuff, but when you get back to it, you realize how greasy it is, or salty, or..................................... Life is funny that way.

BUT NOT CARL'S JUNIOR, OR ARBY'S REUBEN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[farmall]

Aircraft fuel tank sealant is glorious and every mechanic should try a kit. When the Air Force threw away "expired" tubes they never made it to the dumpster but now I'm retired I buy kits to keep handy in my fridge.

https://www.aircraftspruce.com/catal...al09-04612.php

It's what seals basically all the aircraft fuel tanks, countless cockpit transparencies, panels as faying sealant, and more. I sealed GM diesel timing chests at Incirlik when the local motor pool went on strike and it worked a treat. It's not like RTVs or caulks and cares nothing for fuels, hydraulic fluids etc.

I cut an access hole in my Chevy bed for future fuel pump access and every truck I have will grow one if it needs a fuel pump. I slather bed bolts with industrial anti-seize before reinstalling them on every truck I get and of course all the fuel tank threaded hardware.

[farmersammm]

I was about to lower the bed onto the truck today, then it hit me.

I wasn't absolutely sure that the lock ring on the rear tank is fully seated I was only able to hand tighten it, then hit it with a drift to turn it tighter. Broke off one of the ears on the thing, and decided I'd best leave it alone. So, I'm not confident it's as tight as it should be. I don't need any leaks.

This puts the stinkin' brakes on the whole thing

The factory manual calls out the torque at 40-50ft/lbs on the ring. They also suggest using a strap wrench to tighten the piece of crap. I don't have a strap wrench big enough to go around the ring, and furthermore.......I think strap wrenches can break plastic stuff when they cam over to tighten the strap. The plastic ring is 27yrs old, and it's brittle.

Now I gotta make a stinkin' tool for the job.

It's basically just a version of commercially available sender unit lock ring tools. I'd buy one, but they don't have any locally, and it's a special order. It's complete except for welding a nut to the thing so a socket will fit it.

I just want to see this damn thing out of the shop. I'm sick of looking at it. And I'm having to use the pickup to haul hay in from almost 65 miles away ONE F'N BALE AT A TIME. Weather is supposed to warm up soon,,,,,,,,,,,,,God I hope so. But we're supposed to have rain Fri thru Sun. I gotta get this thing put together tomorrow. It doesn't have working windshield wipers, so it can't be driven when it's raining. I have another motor for the wipers, but it has to be pulled from the parts truck.

Still gotta get to Tulsa to pick up the filler hose stuff.

If all goes right, the bed ought to be on tomorrow evening. K'kins has to help me to put it on. Takes two people.......one on the crane, and a ground person to keep it lined up while it's being lowered..........without hitting anything important, like the cab or gas tanks.

[farmersammm]

Aircraft fuel tank sealant is glorious and every mechanic should try a kit. When the Air Force threw away "expired" tubes they never made it to the dumpster but now I'm retired I buy kits to keep handy in my fridge.

https://www.aircraftspruce.com/catal...al09-04612.php

It's what seals basically all the aircraft fuel tanks, countless cockpit transparencies, panels as faying sealant, and more. I sealed GM diesel timing chests at Incirlik when the local motor pool went on strike and it worked a treat. It's not like RTVs or caulks and cares nothing for fuels, hydraulic fluids etc.

I cut an access hole in my Chevy bed for future fuel pump access and every truck I have will grow one if it needs a fuel pump. I slather bed bolts with industrial anti-seize before reinstalling them on every truck I get and of course all the fuel tank threaded hardware.

That looks like good stuff. I never heard of it, so it's a valuable link

Does this stuff come off if you have to take things apart?

Yeah, I'm religious with anti seize. It's cheap insurance for the future. I wish they'd take the time to put the stuff on manifold studs at the factory. It's almost like they WANT you to break them.

[whtbaron]

"I was about to lower the bed onto the truck today, then it hit me." Quote...


Sounds painful...

[12V71]

Gotta love owning trucks... Got home today and saw a puddle under the SuperFord . Frikken water pump, at least the V10 has one that's easy to change.

[farmersammm]

Fifteen Seconds of Fame

Specialized tools take a bit of time to make.....................ALL FOR ABOUT 15 SECONDS OF USE The ring turned almost another half turn from where I thought I had it properly tightened. So, it's all good And no broken ears on the ring.

If it has to be right, it has to come from Uranus

Feel free to call one of our charmin sales reps for assistance.

[farmersammm]

Gotta love owning trucks... Got home today and saw a puddle under the SuperFord . Frikken water pump, at least the V10 has one that's easy to change.

I have a split seam on the top tank on the F-150. Been a slow leaker for years, until this week. Now it's taking a gallon of water about every 100 miles, or less. Drove 120mi today, and it was pretty hot by the time I got back. Problem is...........if you have to add water on the road, you have to sit quite a while to let the water cool down so it doesn't boil out of the neck when you open it up.

Fill it up, and it blows water out fast. Once the water level goes down, the leak slows down because the level is below the split seam. But by that time, the heat starts to rise pretty fast. PITA.

[12V71]

I have a split seam on the top tank on the F-150. Been a slow leaker for years, until this week. Now it's taking a gallon of water about every 100 miles, or less. Drove 120mi today, and it was pretty hot by the time I got back. Problem is...........if you have to add water on the road, you have to sit quite a while to let the water cool down so it doesn't boil out of the neck when you open it up.

Fill it up, and it blows water out fast. Once the water level goes down, the leak slows down because the level is below the split seam. But by that time, the heat starts to rise pretty fast. PITA.

Ouch, that can be hard on heads and blocks. Had a series 60 Detroit in the shop awhile back that overheated and junked a $3000 head casting. Plus 3 cracked pistons and scored liners. Computer tattletale said it hit 240 degrees several times.

[farmersammm]

This one could be an easy fix. I have a good radiator(i'm assuming) in the parts truck. But, the price of radiators is so reasonable nowdays, that it might just be as easy to get a new one. Radiator at Autozone, w/o Air Conditioning, is $149. Messing around with the parts truck just takes more time, and it's no guarantee that the radiator in that truck is any good.

It's the hoses I dread. Aftermarket stuff sometimes has different diameter outlets/inlets than the original. It can be a real mess trying to find the right hose. I think I had this problem when replacing the top hose on this truck years ago. IIRC, a replacement water pump had a different sized outlet, and it was a mess trying to find a hose with two different diameter necks. It's been such a long time that I can't remember exactly, but I do know I had a hose issue.

[Zimm]

Watch the bottom hose on that F150 too. There are two different types. One with an air pump, one without. Guess how I learned that?

Put a new radiator in mine years ago. Pretty easy as I recall. Hell of a lot less time and bother than driving around with a couple gallons of water.

[farmersammm]

The Beagle Has Landed

Pressure washed the underside to make it easier to work with.

And she's on Took the better part of the afternoon to do all the bolts, and electrical. I'm too damn old to be crawling under this stuff anymore.

Do the fuel fill stuff in the morning, and it's out the door.

[farmersammm]

Put about 200 miles on the truck yesterday, and it ran fine.

BUT I CAN'T GET GAS IN THE BACK TANK. I need to figure out if the tank vapor valve is no good, and not letting air escape to the charcoal cannisters. Or maybe the cobbled together filler neck is no good.

I know that filler necks are no longer vented, and the air is vented somehow through the EVAP system, but I need to figure out how it works.

[farmersammm]

No work today..............rain day.

On the flip side Because I spent a good deal of the day on the road yesterday bringing hay back FROM THE OTHER SIDE OF THE MOON, I had a pizz poor Beer Nite. Actually NO BEER NITE So K'kins, being the wonderful woman that she is....................."Well it's been a rain day, and nothing getting done, so you can do your regular Beer Nite a day late"

This gives me ample time to contemplate the vagries of the market, my navel, and the inexplicable workings of the EVAP system on a Ford...............and get lit at the same time

[12V71]

Put about 200 miles on the truck yesterday, and it ran fine.

BUT I CAN'T GET GAS IN THE BACK TANK. I need to figure out if the tank vapor valve is no good, and not letting air escape to the charcoal cannisters. Or maybe the cobbled together filler neck is no good.

I know that filler necks are no longer vented, and the air is vented somehow through the EVAP system, but I need to figure out how it works.

I always went just above the filler hole where the nozzle fits and drilled 2 of the biggest vent holes that would fit. Push a magnet through the nozzle hole to collect the chips. It may still fill slower than normal but it will fill.

[farmersammm]

I always went just above the filler hole where the nozzle fits and drilled 2 of the biggest vent holes that would fit. Push a magnet through the nozzle hole to collect the chips. It may still fill slower than normal but it will fill.

I'm above the inlet to the actual tank.........so that checks.

I thought about the stupid unleaded flap they have on anything built after the late 70's, and know that there's no air escaping the tank when gas goes in. Like you say, I might be at the point where I need to drill some holes, or eliminate the flap entirely.......hog the thing out.

The missing portion of the whole filler system on the back tank is the little hose that fits inside the larger hose. I'm sure this is the key to the whole problem. The shutoff system on the gas pump is being fooled by this. It was the same on the old 78 Powerwagon. You had to drizzle gas into the tanks. The air escaped through the filler neck that the fuel was going though.

[farmersammm]

I read something about how gas pumps work. It explained how the shutoff valve works inside the pump nozzle, but it was a bit beyond my patience, and understanding. Something about vacuum, or something like that.

Anyways, after reading this stuff, I thought that the little inner filler hose is unobstructed, puts gas in the tank, and the displaced air exits somewhere else. The pump just "knows" that everything's ok (confused shrug)

[farmersammm]

I mean HELL.............these damn things took gas in the old days

[farmersammm]

And, I might of made a mistake when I cobbled together the new filler neck. None of the off the shelf stuff would work, so I made a substitute. I might have made it with a too small opening.

I used the original filler neck, and married it to some sch80 pipe to transition to the existing filler hose. I might have made the opening in the sch80 too small...........I dunno. It was a saddle fit on top of the sch80, with a hole in the sch80 to take the gas.

The camera is out in the container, so I' have to post some pics tomorrow.

[farmersammm]

I think the small tube fools the pump into "thinking" it's just an extension of the nozzle.