Fuel starvation issue

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I will keep this simple. This 1984 FJ60 is box stock and mostly original.

I have driven this 1984 FJ60 a few hundred miles without any issues then one evening I filled it up with gasoline and went to go play. About 10 miles after leaving the gas station it stumbled and died. I blew out a very dirty fuel filter and reinstalled it. That got me about 5 miles which were enough to be back in town. I blew out the fuel filter two more times on the way back home.

Since then, I have replaced all rubber fuel lines. Fuel lines have been blown out. Fuel pump replaced. Fuel filter replaced. Carb drained and needle and seat cleaned with carb cleaner. Carb has not be gone through because when the carb has fuel getting to it, it runs very well. Fuel tank drained, filled and drained two more times.

In the morning, the FJ starts good and runs great. But it will only go about 8 miles and then the fuel filter runs dry. If I let it sit overnight, then it starts and runs perfectly for another 8 miles. This time that it occurred I blew backwards through the fuel filter (which was clean) until I could hear bubbles in the tank.

The FJ started up and I drove it 8 miles back home. Once I am at home and let it sit for 45 minutes, the fuel filter is clear full and there is an occasional bubble going backwards through the filter to the tank.

Three possibilities: 1) vapor lock is happening. 2) Fuel pickup screen is plugged from potential bad gas from the initial start of the problem. 3) Fuel lines reversed on the fuel pump or at the tank.

Thoughts from the forum, please.
 

cruisermatt

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My thoughts are that you should determine those three things you listed aren’t issues and then come back.
 

3_puppies

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IMHO vapor lock is almost a non issue with todays gasoline, and it surely wouldn't happen in 8 miles, and it would happen between the fuel pump and carb
there is no screen or sock on the 60 series US spec gas pick up tube, it is just an open tube in the lowest part of the tank.
I can't remember how low the return side dumps back into the tank,

my best guess would be either the pickup tube has a pinhole in it where it comes out of the top of the tank or you have a pinhole in 1 of the metal tubes running along the frame rail.

will it die if running a high idle sitting in the driveway?
try running the fuel pickup into a 5 gallon can of gas and see if it happens

one other thought would be the tank is not vented and you are creating a vacumn in the tank and it won't suck gas. try running without the gas cap.
 

RodrigzCrzr

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You may have debris in the float bowl of your carb. And like 3_puppies said possibly the fuel pick up in the tank is clogged.
 

cruisermatt

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Paul is right, there isn't a pickup screen on 60 tanks. I was thinking of 62 pumps.

Although not sure about vacuum theory. Fuel evaporates and causes pressure, not vacuum. Running without the gas cap is an easy enough test though.
 

3_puppies

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Paul is right, there isn't a pickup screen on 60 tanks. I was thinking of 62 pumps.

Although not sure about vacuum theory. Fuel evaporates and causes pressure, not vacuum. Running without the gas cap is an easy enough test though.
my theory on the vacumn in the tank is drawing gas out of the tank and not replacing it with air/atmosphere, but usually would take longer than 8 miles, more like 20-30 miles
 

morganism

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Sounds like it may b be as Puppies is expousing.

Do you have a big whoosh when you open the tank cap?

Try unhooking your charcoal cannister hoses on top, spray in WD40, or PB blaster in both holes. Now switch hoses from tank and return. Cannister valve is a known bad valve.

See if it works.
 
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Try what morganism said above. I had a similar problem once due to the tank pressurizing because of a bad charcoal canister. Swapped the two hoses on top around and good to go.
 
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Thanks, folks for all of this feedback. The fuel lines are in the correct position. This is a rust free chassis and after a thorough inspection of the steel lines the look good and when under pressure there are no wet spots on the lines. It will run in the driveway all day, enough fuel is pumped to the carb that it will run at high idle for a long time. As far as the tank pressure goes, yes, it does vent off when the cap is opened. I already tried driving it with the cap off and the same fuel starvation issue happens. I have not reversed the charcoal canister hoses, but with the problem not going away with the cap off I did not think that was the issue. I will try that hose switch for sure.

Let me add an observation that came to me last night: the two times this has happened were when I filled the gas tank up. I have no clue if this is a factor or a coincidence. The first time I drained the tank and change the fuel pump I only put in 5 gallons of gas and it seemed to run fine, so I filled it up. And after 8 miles the fuel filter went dry. Seven to 10 miles of driving on a full tank of gas seems to be a pattern.
 
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My thoughts are that you should determine those three things you listed aren’t issues and then come back.
The fuel lines are in the correct position. This is a rust free chassis and after a thorough inspection of the steel lines the look good and when under pressure there are no wet spots on the lines. It will run in the driveway all day, enough fuel is pumped to the carb that it will run at high idle for a long time. The last thing is to pull the tank out, yuck. Thanks for the quick reply.
 
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Sounds like it may b be as Puppies is expousing.

Do you have a big whoosh when you open the tank cap?

Try unhooking your charcoal cannister hoses on top, spray in WD40, or PB blaster in both holes. Now switch hoses from tank and return. Cannister valve is a known bad valve.

See if it works.
Let me add an observation that came to me last night: the two times this has happened were when I filled the gas tank up. I have no clue if this is a factor or a coincidence. The first time I drained the tank and change the fuel pump I only put in 5 gallons of gas and it seemed to run fine, so I filled it up. And after 8 miles the fuel filter went dry. Seven to 10 miles of driving on a full tank of gas seems to be a pattern.
 

Seth S

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You could put together a small 2 gallon test fuel tank that you strap into the passenger side of the engine bay and block off the stock fuel tank. Take the truck for a drive and see if your problem is gone. Might be a way to rule out the fuel tank or narrow the problem to the fuel tank or vents.
 

morganism

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Do you have a local Toyota dealer?

These tanks have a recall on them, with bad hoses from the vapor condenser behind the rear cargo panel. Get a replace for free, and then start looking again.

Also, that fast of starving may be a overheating fuel relay.
Do you have any weird , partial lighting of dash lights?
Have dimming headlights when idle?
Does your main Alternator wire get really hot when idling?

Clean the hold down bolts on the coil cage, and connect a wire from the corner of the ignitor case on top of coil, to a solid ground on the wheelwell, and see if it changes anything.
 
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Latest update, I drained the tank for the third time and the fuel ran out clean with virtually no debris. The fule flow is very low, enough to high idle and fill the crab to the center of the sight glass. But when driving type fuel demand is required it still staves out. There are no restrictions in the fuel line to the new fuel pump. I set up a remote fuel jug and ran a fuel line directly to the new fuel pump and it made zero change in fuel delivery. That eliminates all potential problems from the inlet of the fuel pump on back to the tank.

Next, I pinched off the return line at the new fuel pump and that made no change in the fuel flowing into and through a new fuel filter. Then I pinched off the inlet hose to the fuel pump and waited for a minute or so. When I released the clamp, fuel from the fuel tank whooshed into the fuel filter. That indicated that the fuel pump was able to "Pull" fuel and it confirmed that there was ample flow from the fuel tank.

So, why is there so little flow into the fuel filter and up to the carb? Remember, the FJ runs really well when it has fuel.
 
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Do you have a local Toyota dealer?

These tanks have a recall on them, with bad hoses from the vapor condenser behind the rear cargo panel. Get a replace for free, and then start looking again.

Also, that fast of starving may be a overheating fuel relay.
Do you have any weird , partial lighting of dash lights?
Have dimming headlights when idle?
Does your main Alternator wire get really hot when idling?

Clean the hold down bolts on the coil cage, and connect a wire from the corner of the ignitor case on top of coil, to a solid ground on the wheelwell, and see if it changes anything.
There is a fuel replay on a carburated FJ? It would not surprise me with the amount of emission crap under the hood. There are no lighting issues. Headlights and dash lights remain constant. None of the alternator wiring gets hot.

Yes, I do have a Toyota dealer close by. Are they honoring a fuel tank recall on a 1984 model?

P.S. I just posted an update with what I have found out since yesterday.
 

RodrigzCrzr

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I also want to add that it could be your fuel plunger. When it is idling do you rev it as it is sitting there and does the fuel starvation act up again?
 

morganism

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Recall for 60, out of tanks for 62

Lookup Safety Recalls & Service Campaigns

Not another fj60 gas tank recall issue. Called Toyota corporate today.

A lot of folks take this, get the new tank, and put in an extended range tank, then sell the new spare, to pay for a swing away bumper for tire.

I have to agree that it may be a sticking float valve, or a plugged screen from the fuel intake. There is a little one inside the carb.

PS, they are out of some of the short fuel lines inside the tank, you have to get an OK that they can cut some to length. Don't let em tell you no, they have to try and buy the truck if they cant repair it. They price it by looking at the rust underneath !
 

OSS

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Before I pound out my manifesto, I've got one question:

Was the fuel pump replaced with a genuine Toyota pump? Or is it an aftermarket China crapolicus?

If Shanghai parts are bolted to your 2F, that's likely the elephant under the hood.
 

NeverGiveUpYota

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Before I pound out my manifesto, I've got one question:

Was the fuel pump replaced with a genuine Toyota pump? Or is it an aftermarket China crapolicus?

If Shanghai parts are bolted to your 2F, that's likely the elephant under the hood.
Now why I didn’t speak up yesterday when I started writing that exact response? ;) You’ve trained me well other than being too shy at opportune times.
 
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