(SOLVED!) 1HD-FT fuel starved at startup (2 Viewers)

[overpakd]

I have a 95 HDJ81 with the 1HD-FT. Recently, she's decided not to start after sitting for a long while (usually overnight). Pumping the accelerator while cranking will finally get her going. 24V starter is strong (replaced ~40K km ago by PO) and cranks hard as long as the batteries will hold.

I had not replaced the fuel filter yet as it looked very new and the Japanese appeared to have serviced *everything* before auction. I went ahead and replaced it anyway. The old filter did not have any obvious water or sediment in it. With the new filter installed, I primed the hand pump until "hard" and still had a very similar issue starting immediately after that. The idle adjustment screw had been weirdly backed way off since I got it and I hadn't adjusted. I had taken to using the rpm hold knob on the dash to keep it idling where I wanted (which wasn't all that reliable anyway), so I adjusted that yesterday as well. I honestly thought maybe that somehow solved it, but the problem was back after sitting a few hours.

Once started, she absolutely purrs at a very consistent 800 rpm idle, and I sense a little more power in early off-boost driving with the new filter. It's only cold starting that's the issue.

After pumping the fuel filter hand pump, I can hear fuel gurgling - it's a guess, but sounds like it's fuel retreating down the fuel line pre the filter. The hand pump does not stay hard (it seems like it should, but I don't know). I cannot find any evidence of a fuel leak anywhere, but maybe there is an air leak?

Any suggestions on what could be wrong and where/how to look next?

 

[overpakd]

Update: This is related to the fuel cut off solenoid. With the ignition "on", I'm measuring ~10V at the solenoid. Connecting 12V from the battery positive terminal directly to the cut off solenoid (challenging!) immediately clicks the solenoid and she'll start right up.

The correct next step is probably to troubleshoot that 12V ignition wire along it's path to the solenoid. I have no idea how to get in there and follow that back to it's origin - much less replace it if that's needed. Does anyone have any tips or just know where the next connection point in the harness is? Pictures are worth 1000 words here. I'm a novice at interpreting the EWDs, but I don't think anything there indicates *where* a harness or connector is physically located.

As an alternative, I'm considering just jumpering another ignition 12V source from somewhere accessible above on a new wire to the cut off solenoid. I can't immediately locate ignition switched 12V from above. Anyone know a good spot?

Incidentally, it may also be the case that my batteries are slightly weakened. I'm getting 12.3V when off. "Fully charged", I'd expect to see 12.6V, (and they may just not be fully charged right now with all my testing). But even with a full 12.6V, if I apply a 2V drop (roughly what I'm seeing at the solenoid), it wouldn't matter if the batteries were perfect. I checked the dates on the batteries and they're about 2 years old. I could try replacing them, but that's expensive and seems like the wrong fix (if it would even fix it).

 

[overpakd]

TLDR: the truck starts perfectly now. Just bump the key and boom. Better than new. Corrosion/Oxidation primary suspect.


The only problem with that summary is I can't be sure why it works so well now. I found that I had, while trying to hot-wire the cut off solenoid, shorted something and blown the IGN fuse. This meant I could *only* get power to the solenoid when hot-wired. I replaced that fuse and the truck was starting well without the hot-wired solenoid. I decided to leave that jumper wire connected and available in an emergency, so I protected it and taped/tied it out of the way and properly tightened the nut on those connections to the solenoid. After everything was tightened and tidied up, she is starting better than ever.

The only thing I can guess was happening is that over the last 28 years, that connection (even though protected with a nice little rubber boot) has oxidized and finally created enough resistance that the solenoid wouldn't fire. Disturbing and retightening the connection corrected (at least temporarily) this problem and now I get fuel *immediately* on cranking.

I plan to leave the jumper wire available for a week or so just in case, then take that connection back apart, remove the jumper wire and properly clean the terminal and connector, apply a little electrolytic grease and tighten it all back down and hopefully be problem free for another 28 years.

 

[mudgudgeon]

Solenoid may have been a bit sticky due to old fuel if it's been sitting a while.
Jumping it may have busted it loose.

Check your battery voltage with a mutimeter while under load such as starting. Voltage should start above 12 bolts at both batteries.

If one battery is weak, it will drag the other one down to an early death.
Replace both at the same time as a matched pair, ie, the same type/brand/specs etc

 

[overpakd]

Well folks, no joy after all. A couple days of perfect starting gave way to the same issues again. Still having cold start issues even having reseated the fuel cut solenoid wire that I thought solved it. I'm *fairly* convinced I'm chasing an air/vacuum issue in the fuel lines.

Here are some more clues from my investigation in no particular order:

- There is a vacuum that builds at the fuel filler cap. When I refuel, especially when the tank is low, air is sucked in when I open the cap. Also, when filling the tank, after the pump shuts off, there is a slow, rhythmic gurgling coming from the filler pipe. Like it's burping air and letting the fuel drain down the pipe (no early cutoff problems or other issues *while* fueling though). Incidentally, opening the fuel filler cap while cranking does not change the failure mode. I assume there is already air in the lines (if that's the issue).

- After hand pumping at the filter, There is a gurgling sound coming from either the main fuel line before the filter or the return fuel line. This *sounds* like fuel retreating down the main line back toward the tank, but haven't confirmed that with any tests. Maybe this a normal sound of dribbles of fuel forced through the IP and to the return line? I don't know enough about how this *should* work.

- Pumping the hand pump ad nauseum does not appear to help the cold start (inconclusive / not tried enough times to be sure)

- There is >12V at each battery (measured directly across their terminals) before cranking. Still need to measure this with a helper *while* cranking, but I *think* power is good.

- There is 10.75V at the fuel cut solenoid when IGN switched to on. This appears to be plenty to kick the solenoid despite earlier misgivings and tests. Blowing the IGN fuse confused the testing. See below.

- This one is super confusing to me: When I apply 12V directly from the battery to the fuel cut solenoid, the solenoid clicks as expected, but I always also blow the IGN 7.5A fuse. The jumper wire is securely tightened with a similar ring terminal to the fuel cut solenoid in tandem with the existing factory ignition wire. The loose end is carefully touched to the positive battery terminal. No reason I can see to think this would cause any kind of short or overcurrent to blow the fuse, but it does.

- Another confusing one: On a fresh battery, but cold start (think long drive and then shut-off in the driveway overnight), the starter will spin and spin and spin with no indication of any desire to turn over (zero fuel). I'm reluctant to immediately go for the solenoid jumper wire in this case because of the previous finding, but it's probably worth a 7.5A fuse tomorrow morning to try it. Anyway, *if* I continue to crank and crank (crank for 3 seconds, rest, off, on, repeat), the battery(ies) will eventually start to sag. **When the batteries start to sag, she starts - chug, chug, fire**. Every time, it's when the batteries finally start to sag and starter slows a little. This is obviously a tense moment because it feels on the edge of too weak to start, but it also seems the ONLY way she will start when in this state. This makes zero sense to me. Could be a red herring because of the time needed to finally get air out and fuel in where it's supposed to be and this magically coincides with the time needed to sag the batteries, but this effect has been VERY consistent throughout this issue.


Obvious next steps:
- All the fuel hoses in the engine bay look like new rubber, but I'm going to pull off all the old finger clamps in favor of tightening hose clamps as a start.
- I may grab some 1/2" clear piping to watch the fuel through the main line, from the filter to the IP and from the IP back to the return. The hard lines also "look good".
- I have not gotten down under to see if I can inspect the hoses at the tank on the other ends of the hard lines. If I can reach those, I'll try new clamps there as well.
- Is the evap check valve accessible and could it be bad?
- I don't want to just replace the filter hand pump assembly for cost and effort, but is there a good way to test for a leak there? Clear hose again? More than willing to replace bad parts, but would rather not simply as a diagnostic.


If you got this far, THANK YOU for reading and pondering with me. Any other thoughts/suggestions/next tests?

The good news is I continue to trust her and take her on adventures and we had a great outing in the mountains this weekend. The bad news is I continue to trust her and take her on adventures and my daughter and I are headed on a ~16 hour round trip next weekend. At this point we're just planning to do so with fingers tightly crossed and all tools and patience on board.

 

[mudgudgeon]

All the fuel hoses in the engine bay look like new rubber, but I'm going to pull off all the old finger clamps in favor of tightening hose clamps as a start.
- I may grab some 1/2" clear piping to watch the fuel through the main line, from the filter to the IP and from the IP back to the return. The hard lines also "look good".

The OEM style clamps are superior to worm drive hose clamps, but, they won't seal a hard or cracked old rubber hose. But neither will a worm drive clamp.

Clear hose is perfect way to diagnose what sounds like an air leak in the fuel system.

Clear hose between pump and filter housing first will show if you have air getting in. Then clear hose before the filter housing will confirm if the filter housing is leaking, or the leak is in a hose before the filter

 

[mudandrock]

Put 12v directly from your battery to the FCO solenoid and try to start. If it’s the same problem then you’re barking up the wrong tree. My gut tells me you’re loosing prime and it’s probably your hand primer. Ive also experienced similar issues when an injection pump starts to fail, but check the low hanging fruit first

 

[overpakd]

Ok, back for a positive update!

TLDR: Air in the injector lines was the apparent issue. Starting like a dream again.

I bought some clear PVC hoses to replace the supply line to the filter/pump housing and from the filter to the injection pump. (side note: all three hoses at the front of the system are different diameters. Supply to Filter: 12mm, Filter to IP: 10mm, IP return: 6mm. I haven't messed with the 6mm return line yet, but will replace it with OEM hose when I finally replace the others.)

I unclamped and remove the filter side of each hose first and quickly turned the hose down into a cup to see what fuel I could capture from the line... zero. All the fuel had retreated from those lines while sitting idle - a good clue the system wasn't air tight. Upon inspection the original rubber hoses were beginning to crack and split at the ends and the clamps were weak, so I suspect this was allowing air into the system in certain conditions.

Attaching clear PVC hoses with screw type hose clamps allowed me to hand pump the system and fill it with fuel. The line from the filter to the IP, however, stayed half full of air no matter how much fuel was pumped. To purge the line, I opened the clamp and slid the hose back just enough to crack the seal and let air spew out until the hose topped off with fuel. This was easy with the clear hose, but I'm not sure you could tell that you'd properly purged this with a rubber hose since air pockets wanted to hide in the lower bends of the hose. It seems like this would be a problem every time you change the filter. I will find out what it's like to purge the black hose soon enough.

So, with those fuel lines nice and full of fuel, I hand pumped till stiff and gave her a crank. Slow "dry" start, but she did start. I messed around with the hoses for a day or two between starts and long idles to see if more air was being introduced or if the problem could be somewhere else. The symptom really never changed, but the clear hoses stayed full of fuel for days.

I read in a couple places a suggestion to crack the injector lines one a time while running to purge the IP and those lines of air. I really didn't want to do that if not necessary, but today decided to give that a go. First, I cracked the main inlet hard line (which is just an extension from the clear hose I'd already "purged", but it's connection is still higher than the hose and I figured there could be an air bubble there. With it slightly cracked, I gave the pump one push and diesel flooded out of that connection. To be really sure, I probably should have done that a few times, but I just tightened it back up. Gave her a start, but had the same slow dry start and finally turned over.

With the motor off, but the key turned to on (fuel cut solenoid open), I cracked loose the first injector line up top and gave the pump a few pushes. No detectable fuel coming through, but I did have a towel stuffed under it and might not have been able to tell if it was. Figuring fuel wouldn't be necessarily flowing through there with the IP not turning, I tightened that injector line back up and gave her a start. Bumped the key and she roared to life. So *maybe* this step released the problem air even though it didn't seem like anything happened.

For good measure, while running, I cracked each injector line open just enough that the motor ran a little rough from starving and fuel spritzed out of the line then retightened. I did this at every cylinder.

It's only been an afternoon since these steps, but the 7-10 test starts since have been absolutely perfect. No delay. Bump the key, starts immediately. Fingers crossed this was the only issue. I may have to repeat this process when I replace the clear lines with the correct rubber hoses and reintroduce air into the system.

Will update again if the issue returns. Thanks all for following the saga

 

[Squash]

No need to crack the injectors.
Once fuel arrives these things just clear themselves.
Key is never run your diesel dry. If she hesitates or stalls do not turn the engine over unless absolutely necessary.

 

[overpakd]

No need to crack the injectors.
Once fuel arrives these things just clear themselves.
Key is never run your diesel dry. If she hesitates or stalls do not turn the engine over unless absolutely necessary.

I assume that's the normal case, but this started for me suddenly and I've never run it even close to dry. In any case, injector line purge seems to have solved it for me this time and hopefully won't have to revisit that method.

 

[mudgudgeon]

I assume that's the normal case, but this started for me suddenly and I've never run it even close to dry. In any case, injector line purge seems to have solved it for me this time and hopefully won't have to revisit that method.

Cracking the injectors wasn't the solution to air getting into the fuel.
The fact there was no fuel at hoses when you disconnected them at the filter says air was getting in to the fuel lines. Most likely through cracked/ hard hoses from what you've described.
Fresh fuel hose throughout the system is probably good PM at this point. If your problem recurs in the near future, then hoses are out of the picture, and your primer pump/ filter assembly is the main suspect

 

[dudwire]

Currently diagnosing the same issue myself. After sitting a few hours it will crank for a few seconds or so before it starts. Once its started you can switch it off within a couple seconds of running and it'll start right back up instantly like it should.

I done some testing on mine today with some clear hose and found it was pulling air before the pump after the second fuel filter with the water sensor - it did not suck any air into the line at idle, only once the engine was under load or at high rpms. Between the first and second filter it had no air leaking into the lines.

I've replaced the factory clamps with worm style ones for now to see if it makes a difference in my case as you could easily pull the fuel line off with the old clamps on.
Next step will be to replace the fuel line and/or water sensor.

 

[overpakd]

Mine is at it again. 3 days of perfect starts had me convinced it was solved. I still have the clear lines on. While I don't *see* air in these lines, the hard PVC material doesn't actually seal perfectly even with very tight worm clamps. Wiggling the hose from the filter to the IP can introduce small air bubbles. New rubber hoses just arrived, so those will go on today which should correctly seal these. Presumably, I will have to crack the top of the system once again this time. If the correct hoses don't solve it, I'll order the new filter pump head.

 

[mudgudgeon]

Mine is at it again. 3 days of perfect starts had me convinced it was solved. I still have the clear lines on. While I don't *see* air in these lines, the hard PVC material doesn't actually seal perfectly even with very tight worm clamps. Wiggling the hose from the filter to the IP can introduce small air bubbles. New rubber hoses just arrived, so those will go on today which should correctly seal these. Presumably, I will have to crack the top of the system once again this time. If the correct hoses don't solve it, I'll order the new filter pump head.

I have a string preference for the factory spring type clamps vs worm drive clamps.

The worm drive tend to pinch the hoses leading to leaks

 

[overpakd]

Replaced hoses again with newly arrived good, black, (compressible) rubber. Hand pumped at the filter til stiff. Problem is the motor still wouldn't start. Previously, long cranking would eventually get fuel and she'd start and run fine, but now she just spins. I'm making assumptions that air (at/in the injection pump or beyond) is still the problem, but I'm not sure what else to do to clear it. I tried pumping the hand pump with the key turned to On since that will open the solenoid. Overflow fuel is still bypassing to the return hose while pumping. I did check the fuel cut off solenoid again to make sure I wasn't being dumb, but voltage is still good and relay is clicking.

Despite having never actually run the motor dry, it seems that's what I have to treat this as. I read someone suggest cracking each injector line and hand pumping while cranking until fuel started to dribble out. I tried that but never got any fuel at any injector. The injector pump bleeder screw (when open) still flows generously with half a hand pump, so plenty of fuel on the way *into* the pump.

I switched back to clear hose from the filter to the IP. It's very easy to get a large air gap in that line that needs to be purged. so maybe that was an issue with the rubber hose in place and I just couldn't tell. I had already tried cranking for a long time with the injector lines barely open and hand pumping to the point that the batteries weakened too much for the 24V starter relay. She's on the charger now, so I can test more tomorrow having purged that clear line of all air.

I think someone mentioned pulling glow plugs in order to crank with no compression, but I believe the 1hd-ft uses a pre heater (with a glow screen maybe) instead? (Incidentally, that pre-heater seems to work fine. Intake pipe is warm and I hear the pre-relay heater click on and then click off after 81s (per the FSM). I don't think there are plugs on this. Any way to make cranking until fuel arrives easier/more correct?

 

[Squash]

Ft has a screen. No pulling injectors.
I would put a clear hose from the filter to your IP. Leave the hose in place making certain the clear fuel is passing through. If bubbly then bypass the filter with another clear hose. If fuel clears up then your filter housing is sucking air. If bubbly then move towards the tank.
Also, pump the primer till it's stiff, if it took a bunch of pumps then something is dickered.
The other method is prime the primer till stiff and while someone tries starting, you pump the primer in order to keep it stiff. If this happens again something is dickered.

 

[overpakd]

Well, this one has sent me down several investigative goose chases so far. Still not there yet.

I didn't realize it at first while debugging and cranking and cranking and cranking, but at some point the starter noise changed. It sounded like the starter was just free spinning - nothing else was moving, belts, pulleys, etc. so I'm assuming it was not engaging the flywheel. Someone correct me if there's some kind of clutching mechanism involved and I *shouldn't* see the crankshaft turn in this process. I don't know how else it could work, so I think that's my issue now.

After charging both batteries overnight out of the truck, they still were reading a little low and after 1 crank attempt had barely 12V. After fully charging again, took them down to Auto Zone and they still tested low. So, 2 new batteries popped in - same symptoms. *Maybe* this was my original problem, however. Stepping back and thinking about it, I had no fuel issues for a very long time, only after the problem started, did I suspect fuel, change the fuel filter, potentially introduce air into the system, etc. No question the old hoses were cracked, so they could have been contributing, but really wish I'd just thrown batteries at it first now in case.

So... now onto the starter. Why doesn't it engage the flywheel (anymore)? Maybe I burned something up cranking too long trying to get fuel to arrive. So, I went down the rabbit hole of a 12V starter conversion for a couple reasons. 1. Potentially more reliable starts from 1 battery 2. You can get a 12V starter from Toyota locally in a day. Bought a new 12V starter and picked it up Saturday morning.

I wanted to bench test the 24V starter first, but had an absolute bear of a time getting the top bolt and subsequently the starter out of the cruiser. Finally got that done and put it on the bench with one fresh 12V battery. Everything tested well per the FSM. All continuity correct. All operations - pull-in, hold-in, unloaded operation - work fine. So... not the starter?

Now, I'm at a loss (again). Today, I'll connect the starter back in the truck on the original wiring, but not mounted and "bench test" under the truck. While there are many mysteries to the 24V relay timer, the combo circuit and the starter relay, they all *appear* to be doing what they should as with the key turned, ~24V hits the main lug. I haven't been able to compare the voltage to terminal 50, which drives the magnetic switch because of it's position while mounted. The under the truck test will confirm that today. That said, on the bench, the starter will not spin at all if only the main lug has power (which it always does - ~12V). Only once the magnetic switch is triggered on terminal 50 does it spin AND pull in the pinion gear. So, if I was hearing spinning, it seems like it had to be working.

So, I'll continue the debug path today, but if anyone can help me understand why I would hear that different sound when cranking that seems like the flywheel is not engaged - even with a good starter - let me know. Could the flywheel be not moving? In all my fuel priming, could I somehow fuel locked cylinders that need to be relieved for the motor to turn? Seems like a long shot, but I'm reaching for anything.

Of course, if the 24V starter does exactly the same thing, I may wire up and try the new 12V part, but it just doesn't seem like the issue now. The 24V starter in the truck looks new and was dated with recent mileage (can't remember now, but about 220K kilometers and the truck has 250K now).

 

[overpakd]

No dice. "Bench" tested the starter wired to the truck with the normal circuit but sitting below on a block of wood. On start, it spun and extended exactly as expected. So, assuming I must be crazy and the starter is good, I reassembled. This was somehow easier than it was getting it out, but I guess I'm learning how to maneuver in that very tight spot. Getting a socket on that top mounting bolt still takes a good 5 minutes of effort... Once the starter was back on the truck, I get the same symptom. Starter spins, but flywheel is not engaged (this is my presumption based nothing on the front of the motor connected to the crankshaft moving and the "free wheeling" sound from the starter. So... maybe the starter tests fine under no load, but a clutch in the pinion mechanism is bad so it hits the flywheel and the pinion stops spinning.

After a week of not being able to start my daily driver, I'm on the verge of throwing in the towel and having it towed to a local shop. Feeling pretty defeated, but tomorrow may bring some renewed willpower to continue. Maybe I will swap in the new 12V starter and wire out the 24V combo. If I did burn up a clutch in the starter in this process, I need to figure out how to avoid that if I'm going to put the new one in. Or maybe I didn't do anything and something in the starter has been slowly failing all along. If I do pull it back out, and especially if the new starter fixes it, I will tear it down and inspect the internals.

 

[mudgudgeon]

Does the starter click repeatedly when trying to start? Or click and spin?

Do batteries show 12v under load?

Repeated clicking means the solenoid is not holding itself in. Either not enough current coz batteries no good, or not enough current coz contactors in the solenoid are cooked, or bad ground connection, or bad positive lead connection

If solenoid locks in, and you can hear the starter turning, but engine not turning, there's something wrong with the pinion gear or the engagement mechanism.

If solenoid clicks, and holds, and starter doesn't keep turning, and batteries are holding 12v plus, you might have bad windings in the starter motor. If this is the case, it may test fine on the bench, but not turn over under load.

 

[overpakd]

Does the starter click repeatedly when trying to start? Or click and spin?

Do batteries show 12v under load?

Repeated clicking means the solenoid is not holding itself in. Either not enough current coz batteries no good, or not enough current coz contactors in the solenoid are cooked, or bad ground connection, or bad positive lead connection

If solenoid locks in, and you can hear the starter turning, but engine not turning, there's something wrong with the pinion gear or the engagement mechanism.

If solenoid clicks, and holds, and starter doesn't keep turning, and batteries are holding 12v plus, you might have bad windings in the starter motor. If this is the case, it may test fine on the bench, but not turn over under load.

2 new, good batteries. Starter clicks and holds and spins, but flywheel isn't spinning. Last guess is clutch in the starter pinion gear is cooked and slips when engaging the flywheel. Next step will be try the new 12V starter instead. A shame I didn't just put that one in today, but the bench test of the old one fooled me.