Sounds like you're making progress. You have to make sure that you get fuel up at each injector. Just one injector with air can cause a problem. You need to determine what is the run position on you fuel solenoid. Can you disconnect the fuel solenoid wiring harness if there is an electrical problem. They usually default to run position with no power.
1hdt fuel solenoid (1 Viewer)
- Thread starter franklin40
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- Thread starter
- #22
there is power i’ve tested that. i still wonder if there is a problem with the solenoid itself. i’ll crack the other lines tomorrow. my batteries are dying so i need to charge them first
sorry I got called to diner - back now so a few more suggestions.
if you managed to get fuel to the bleed screw you should be almost home.
re: the solenoid
-many have three positions on, off, and over fuel for the start mode.
-you shouldn't need to take it off - just find the run position.
-have someone turn the key on and off and observe it and see if the electrical control box (edic) moves the fuel shutoff to different positions when the ignition switch is turned on and off. If it doesn't move then something is suspect
like I said, if it has a manual linkage going to the electrical control then see if you can just disconnect it from the electronics and the it will likely default to run position
once you have the run position and fuel up to the bleed screw then crack all injectors one at a time and keep doing it till it starts - that air can be stubborn in the lines
if you managed to get fuel to the bleed screw you should be almost home.
re: the solenoid
-many have three positions on, off, and over fuel for the start mode.
-you shouldn't need to take it off - just find the run position.
-have someone turn the key on and off and observe it and see if the electrical control box (edic) moves the fuel shutoff to different positions when the ignition switch is turned on and off. If it doesn't move then something is suspect
like I said, if it has a manual linkage going to the electrical control then see if you can just disconnect it from the electronics and the it will likely default to run position
once you have the run position and fuel up to the bleed screw then crack all injectors one at a time and keep doing it till it starts - that air can be stubborn in the lines
- Thread starter
- #24
after charging my batteries over night it fired right up today. i let it run for about 15 minutes then shut it off. went to start it again right after and no go. i charged it again for 1/2 hour and it fired right up. still fires up not. never has it had any sign of a weak battery and the starter cranks like crazy. it just wouldn’t fire. now it seems to be running normal. would one weak battery in the system cause the starter to crank off the strong one but the solenoid to to open with the weak one? i’ve had corrosion issues on one battery making me wonder if it’s dying. if they are connected i would have thought all the electrical components would see the same voltage but maybe i don’t know enough
Squash
SILVER Star
Power up the fuel solenoid with direct power from a battery.
You should hear or feel the solenoid click.
Pretty simple way to verify if the solenoid functions properly.
Make very very certain that your battery connections are tight to perfect! A loose battery connection will haunt you.
You should hear or feel the solenoid click.
Pretty simple way to verify if the solenoid functions properly.
Make very very certain that your battery connections are tight to perfect! A loose battery connection will haunt you.
- Thread starter
- #26
i’ve tested and i have 12v to the solenoid. the fact that i can get it to run shows that it must be working. it’s just that’s this problem has been intermittent and seemed to improve after a full battery charge hence my question about having one bad battery in a dual battery system? i’ll try boosting the solenoid but i don’t know if it’ll tell me much now
Disconnect all terminals from both batteries, let them sit for 6+ hours, check their voltages. Ideally they'd be identical. This seems unlikely to be a culprit but electrical issues are a bizarro nightmare and this is awfully cheap and easy to check.
Try wiring the solenoid direct to a 12V source, i.e., not thru the harness or connector, and perform this running test again. A bad wire/ground somewhere in the harness could cause intermittent voltage loss at the solenoid and allow it to close for no apparent reason. This is much more likely a culprit than a bad battery. It wouldn't hurt to pull the solenoid and lube it up as well to ensure it can actuate consistently (or maybe it's always lubed with diesel?). If your solenoid actuates consistently, and fully, and a direct 12V source is applied and the truck still dies, that's not the culprit.
Try wiring the solenoid direct to a 12V source, i.e., not thru the harness or connector, and perform this running test again. A bad wire/ground somewhere in the harness could cause intermittent voltage loss at the solenoid and allow it to close for no apparent reason. This is much more likely a culprit than a bad battery. It wouldn't hurt to pull the solenoid and lube it up as well to ensure it can actuate consistently (or maybe it's always lubed with diesel?). If your solenoid actuates consistently, and fully, and a direct 12V source is applied and the truck still dies, that's not the culprit.
- Thread starter
- #28
i’m driving it today finally and it’s running fine for some reason. it’ll have to earn my trust again though after leaving me stranded!!
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They should fill the fuel lines from tank to pump in no more than 30 pumps. 1HZ fuel filter and primer are the same as 1HD T.
The fuel cut solenoid should make an audible click when its energised.
- Thread starter
- #30
the part numbers shown in the above post were what i was given from ens toyota. when i cross referenced them they came up as 1hz but are definitely different. it’s a filter housing with a replaceable filter element inside. vastly different and won’t fit in the space i have. my primer was pushing fuel out the bleed screw so maybe i’m just not understanding what “firm” means. i can still push the plunger down without too much effort. it’s not rock solid or even really stiff. but it is moving fuel. i’ll jump the solenoid and see. as i said it’s running now. not sure what caused all this to happen but maybe i do have a sticky solenoid or something.
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Squash
SILVER Star
You are wrong not to trust her.
Good batteries, air,fuel and these fawkers will get you where you need to go.
I've added a momentary switch to the starter relay and can start on one battery at 12 volts just in case.
Good batteries, air,fuel and these fawkers will get you where you need to go.
I've added a momentary switch to the starter relay and can start on one battery at 12 volts just in case.
How does that work? Can you post a pic or something? A video of starting with that mod? I'd love to see it!
- Thread starter
- #33
i’ve only driven it twice since it’s failed me so i’m not ready to trust it yet and it’s really only because i couldn’t identify WHY it left me stranded. i’m sure it won’t take long to regain faith. i love this truck and especially this engine. i just don’t like not knowing because then i can’t be ready.
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Well I guess you can say that you have been successful in bleeding the air out of your engine and getting it to run again. By the sounds of it your truck might have been ready to start the night you were working on it it but ran out of battery juice. I've seen this scenario played out before - the battery runs down due to trying to bleed the system then doesn't have quite enough juice left to spin over fast enough to start. Then it is ready to go when charged up again. It's bit of a battery level charge state fine line on this matter.
Did you wind up changing out the primer pump? I would think your question re: compatibility with it being originally for the 1HZ would be answered if it screwed in because of the same thread size. I've had several different primer pumps on my truck and they all do the same job if they are functioning correctly.
Re: diagnosing the original source of the problem. It seems to me that the most likely source would be intermittent electrical power to the fuel shutoff solenoid because of the behaviour - one minute it runs then the next not so more likely electrical then mechanical. Where you able to determine where run position is? If so, then if the problem re-occurs then check the position. Also check the bleed screw and see if it pumps fuel immediately or if there is air. Since there is no E at the end of your engine model # then I assume that it is a mechanical diesel? If so, then if your up in the bush next time the truck decides go on strike then it would be a similar process to re-starting - ensure run position then bleed air before running batteries down - with no electronic input to the engine required.
Some people intentionally choose to delete the edic and control the on /off position mechanically via a cable and that is an option for you here if it truly a mechanical diesel. You may not want to do that but again if you know where run and off positions are then you can temporarily override the edic in a pinch.
- Thread starter
- #35
argh it did it to me again!! i’m stranded but this time inhave a place i’m supposed to be. pulling my hair out. might have to dig into the solenoid sooner than later 
- Thread starter
- #36
after sitting for 20 minutes fired right up! someone please explain what’s happening here!!
i know i need to test the solenoid. i think it’s probably sticking or getting intermittent power. both i can deal with. just need time!!
i know i need to test the solenoid. i think it’s probably sticking or getting intermittent power. both i can deal with. just need time!!
- Thread starter
- #37
so this is the third time i’ve been stranded. i just listened to the solenoid and it is clicking when turning the ignition on. after letting it sit for 1/2 hour it seems to want to start again. i don’t know why
- Thread starter
- #38
again let it sit for 1/2 hour fires right up! does diesel vapour lock?
Squash
SILVER Star
Let it sit overnight and pump the primer, it should get hard or increase resistance in a couple of pumps. If the primer is soft you are sucking air. If soft
try using clear 5/8" hose from the output of the fuel filter directly to the intake of the injection pump.
If you are seeing lots of air bubbles then you have a vacuum leak in the fuel system...sucking air.
If the hose is generally clear and full of fuel then electrical would be my guess.
try using clear 5/8" hose from the output of the fuel filter directly to the intake of the injection pump.
If you are seeing lots of air bubbles then you have a vacuum leak in the fuel system...sucking air.
If the hose is generally clear and full of fuel then electrical would be my guess.
Doesn't sound like air suck to me. If it fails to start due to suck it is not gonna start again after I/2 hour. The air doesn't magically disappear by sitting a little while - it would have to be bled out again.
