Build Grayson's HDJ81 Build Thread

[kendgray]

I used jack stands to hold the rock slider in place with the nose slid into the cutout in the OEM front mudflap. I've seen others mention you can keep the JDM front mudflaps with the full length WKOR sliders and it looked like it was indeed going to work.

I removed and replaced this front hard-line bracket bolt with the included spacer to make room for the U-bolts.

The rear hard-line mount was much more difficult to get to as it is stuffed between the frame and the fuel tank. There was not enough clearance to get the included spacer and extended bolt in this right space so I instead used 4 washers and the original bolt to make room for the U-bolts.

 

[kendgray]

I used a Dremel to clearance this plastic cover for the front left U-bolts and then was able to mount the slider.

The right slider is easier to mount without and hard-line to worry about. The exhaust hanger gave me a bit of a headache as this turned out to be impossible to get into place with the slider already in place. You have to hold the exhaust hanger with the rock slider and lift the two in place together to clear the exhaust pipe. Lesson learned after removing some fresh paint trying to get in in place.

The sliders indeed fit with the OEM mud flaps in place but rubbed ever so slightly. I used a Dremel again to clearance just a bit of mud flaps to prevent rubbing.

 

[kendgray]

Very happy with the finished product. I opted for the 20° angle and the dimples rear plate, a choice WKOR must not see often because they emailed me before the built it to verify I actually meant to order it this way. Not really worried about using this as a step but have a dog and a 9 month old who will soon be crawling in the back and I don't want legs getting stuck in the slider. I also figured the plate will help protect against stuff coming off the front wheel not caught by the mud flap.

 

[kendgray]

Took the truck out for what was likely its first time ever wheeling and had a blast. The rock sliders have already earned their keep.

I was expecting be be limited by my driving ability, open diffs, no front armor, and 35s. I was not expecting to be limited by fueling issues. The engine keeps cutting out when at idle and on a steep incline. I know this is a known issue for the 1HD-T's injector pump, however, I was under the impression that the 1HD-FT's IP sorted these issues out. My initial thought was that this might be related to my kickdown cable being out of adjustment. I adjusted that to within spec and now shifting is smoother and the 4th gear torque converter lockout isn't has harsh. No beans on fixing my stalling issue though...

I'm going to try adjusting my idle screw next as it usually idles around 700-750rpm and isn't normally even touching the idle screw. No sure why this would cause stalling only on an incline and I am doubtful this will fix the problem.

If anyone has other ideas/suggestions I'd greatly appreciate any insight.

Once that is sorted out the next question is whether I put elockers or a front bumper on next...

 

[Delta VS]

Took the truck out for what was likely its first time ever wheeling and had a blast. The rock sliders have already earned their keep.



View attachment 3857146

I was expecting be be limited by my driving ability, open diffs, no front armor, and 35s. I was not expecting to be limited by fueling issues. The engine keeps cutting out when at idle and on a steep incline. I know this is a known issue for the 1HD-T's injector pump, however, I was under the impression that the 1HD-FT's IP sorted these issues out. My initial thought was that this might be related to my kickdown cable being out of adjustment. I adjusted that to within spec and now shifting is smoother and the 4th gear torque converter lockout isn't has harsh. No beans on fixing my stalling issue though...

I'm going to try adjusting my idle screw next as it usually idles around 700-750rpm and isn't normally even touching the idle screw. No sure why this would cause stalling only on an incline and I am doubtful this will fix the problem.

If anyone has other ideas/suggestions I'd greatly appreciate any insight.

Once that is sorted out the next question is whether I put elockers or a front bumper on next...

where is lift pump on these? in tank?

 

[kendgray]

where is lift pump on these? in tank?

I'm still learning this system so someone correct me if I am mistaken but I don't believe there is a lift pump outside of the IP. I haven't taken one apart yet to understand how it works but it's either a separate pump built into the IP housing or the IP serves as the lift pump itself. I've seen people adding in-line lift pumps to 1hd-t's to try to help with consistent fuel delivery but most of what I've read says the 1HD-FT's don't really benefit from one.

 

[Delta VS]

I'm still learning this system so someone correct me if I am mistaken but I don't believe there is a lift pump outside of the IP. I haven't taken one apart yet to understand how it works but it's either a separate pump built into the IP housing or the IP serves as the lift pump itself. I've seen people adding in-line lift pumps to 1hd-t's to try to help with consistent fuel delivery but most of what I've read says the 1HD-FT's don't really benefit from one.

could be fuel filter too. we can discuss when you stop by.

 

[ikarus]

Correct no lift pump. How many miles on your cruiser? Could be age or mileage and your pump needs to be rebuilt

 

[WiscoPat]

Correct no lift pump. How many miles on your cruiser? Could be age or mileage and your pump needs to be rebuilt

@ikarus is correct, there is no lift pump with the mechanical injection pumps on the diesel 80 series. The injection pump is supposed to not require one for normal operation, but does run into issues at steep inclines at low idle.

When I had my 1HD-FT refresh done through Torfab last fall, they added a lift pump from the tank to the fuel filter to help alleviate this and to preserve the life of the newly rebuilt injection pump.

 

[Delta VS]

Wow, no lift pump, that's nuts. Guessing that is your issue @kendgray, as the injection pump likely has a sliding vane type pump on the shaft, good for creating the needed pressure when it has no height difference between tank and pump (or head), but not capable of sucking fuel uphill when the engine is above the tank.

 

[Delta VS]

http://myfirewood.com/TOYOTA/LAND_CRUISER/rm0020e/rm/rm617e/m_fu_0046.pdf

^diagram of pump

You can see on the last page the "fuel pump rotor" and four "blade"s, this is the part we were discussing, and the one talking about above as not being good at sucking fuel uphill.

 

[kendgray]

Correct no lift pump. How many miles on your cruiser? Could be age or mileage and your pump needs to be rebuilt

~54,000 miles on the odometer. Always the possiblity that that was rolled back prior to being sold but I believe it's accurate. If it's accurate, fuel likely sat in it for quite a while which may be contributing. Wouldn't mind rebuilding the IP while parts are available anyway

 

[kendgray]

@ikarus is correct, there is no lift pump with the mechanical injection pumps on the diesel 80 series. The injection pump is supposed to not require one for normal operation, but does run into issues at steep inclines at low idle.

When I had my 1HD-FT refresh done through Torfab last fall, they added a lift pump from the tank to the fuel filter to help alleviate this and to preserve the life of the newly rebuilt injection pump.

Do you know which lift pump they used by chance?

 

[WiscoPat]

Do you know which lift pump they used by chance?

Not off memory, but I'll snap a photo later

 

[kendgray]

http://myfirewood.com/TOYOTA/LAND_CRUISER/rm0020e/rm/rm617e/m_fu_0046.pdf

^diagram of pump

You can see on the last page the "fuel pump rotor" and four "blade"s, this is the part we were discussing, and the one talking about above as not being good at sucking fuel uphill.

Yeah, it's looking like you were right. I get that this level of wheeling isn't really what these trucks were designed to do on a regular basis, but seems a little absurd that Toyota didn't design these with a fuel delivery system capable of handeling a moderately steep incline. Looks like it's time for me to take a dive into what others have done for lift pumps. Thanks for the input again!

 

[SNLC]

You don’t need a lift pump on these engines.

Cheers

 

[SNLC]

And for reference @kendgray the infamous “Sooty” (early HDJ81 1HDT powered 80) owned by Shauno in Australia has done hundreds of trips off road and he has never had an issue with fuel delivery or needed a lift pump. His truck Sooty gets used real hard to on every kind of trail and angle you can imagine.

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Never heard of a single Aussie running a lift pump on any Toyota diesel let along the 1HDx series.

Built a dozen FT/FTEs in our shop and none needed a lift pump.

Now if it is low on fuel (1/4-1/8th tank) and you get on extreme angles, yes you can have some issues. That has nothing to do with the pump though. Don’t wheel it when low on fuel, easy solution.

I have seen one 1HDT powered automatic transmission 80 struggle off-road but that was entirely due to it being an auto and it just not able to get the torque converter to do anything besides complain. In my opinion auto powered diesel 80-series just kind of suck off-road without torque converter and or trans mods.

Toyota built millions of Cruisers powered by the 1HDx series of engines and not a single one came with a lift pump. Go figure.

Cheers

 

[kendgray]

And for reference @kendgray the infamous “Sooty” (early HDJ81 1HDT powered 80) owned by Shauno in Australia has done hundreds of trips off road and he has never had an issue with fuel delivery or needed a lift pump. His truck Sooty gets used real hard to on every kind of trail and angle you can imagine.

4WD 24-7

4WD 24/7 was previously known as 4WD Action. Shaun Whale, Graham Cahill and the boys have been creating the best off-road content for Australians for 20 years. Our YouTube channel is updated regularly with 4x4 customs, tips, builds, reviews and FREE full length episodes showcasing the most epic...

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Never heard of a single Aussie running a lift pump on any Toyota diesel let along the 1HDx series.

Built a dozen FT/FTEs in our shop and none needed a lift pump.

Now if it is low on fuel (1/4-1/8th tank) and you get on extreme angles, yes you can have some issues. That has nothing to do with the pump though. Don’t wheel it when low on fuel, easy solution.

I have seen one 1HDT powered automatic transmission 80 struggle off-road but that was entirely due to it being an auto and it just not able to get the torque converter to do anything besides complain. In my opinion auto powered diesel 80-series just kind of suck off-road without torque converter and or trans mods.

Toyota built millions of Cruisers powered by the 1HDx series of engines and not a single one came with a lift pump. Go figure.

Cheers

No, I think you're probably right. It doesn't make a ton of sense to me that it would be a fuel pickup problem when throttle fixes it rather than exacerbating it. After it cut out a few times, I used the hand throttle to raise the RPMs up to 850-900ish and it didn't stall again.

I've also now found several threads where people had similar issues and lift pumps did not resolve their issues. Unfortunatly none of them ever posted what did resolve their incline stall issue if they ever fixed it.

I'm also still suspect of the A/T contributing here. I need to find something steep I can park the truck on closer than the Owyhees so I can do some real troubleshooting. Would be nice to know if it would die while in neutral on an incline or if it only occurs while in drive.

 

[ikarus]

Yeah I’ve heard of those stalling issues not being able to build boost as well.. I’ve read some threads but would have to dig around. Haven’t experienced it myself. Easy fix though.. manual swap! Haha

 

[SNLC]

I knew I had a video of it around some where.



My buddies HDJ81, 1st gear 4wd low and pedal is to the floor.

That is not a fuel delivery issue. It’s a trans/torque converter issue and as Ikarus says, it won’t build any boost like this.

Most early 81’s also have a solenoid-valve on the p/s box to assist with low rpm’s and when the p/s is being put under load. Ie, they idle up a bit in these conditions to compensate for load on the p/s system. If not working correctly, big tires, rocks, ect it can cause the truck to die or almost die to due low idle dips. We usually get rid of it, it’s a funky system only used on early HDJ81s.

Cheers