My 1st HDJ81 Couple of Questions

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jpsfj60

jpsfj60

10 Year 15 Year
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Dec 10, 2009
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991
Location
Hbg,Pa
Just got my 1st HJD81 and I am very impressed so far
with the motor and stock IP on my 300 mile drive home. Reminds me alot of my Dodge W250.
I am wondering what the fix is for the power mirrors that don't fold in. Have not yet looked into
the problem at all. Just know that they don't fold in when I press the R button.

Next should I tweak my IP like I did to my VE pump on my 6bt? My 81 runs just fine right now with
just 115,000KM on it. I have been reading what everyone is doing and has done to their IP's. What
kind of IP do we have in these HDJ81's? My 81 is a 1990.

What is the most important things I should be checking and looking for so I don't have a problem
out in the middle of no where? What parts should I keep in the rig for back up?
Should I just rebuild my started contacts now before I have a issue?

Have enjoyed reading all the info posted on here about these diesels. I am a landcruiser freak
and always wanted a diesel cruiser since I am a cummins freak too. Hope my auto transmission
holds up better in this 81 than my cummins auto and all the FJ61 autos that went out on me.
Thanks for any and all input to my questions. Can't wait to get this cruiser out on the trails soon!!
 
Welcome to the new obsession.
First thing you should consider doing are the BEBs, aka. rod bearings and bolts.
Second would be to check over the fluids and filters to make sure they are in good shape.
Third - Timing belt and tensioner
Fourth - External Transmission cooler, not found on HDJ81
Fifth - Valve adjust
Sixth - two thousandth on the list will find you...

Seriously it's a love hate relationship you will build with the 81.
I would only consider doing the IP modifications once you find a way to move and or cool down some more air... 3" exhaust and intercooler to keep the motor from meltdown.

You can check out my build thread in my signature for more ideas... the best mod I did was the FZJ80 bigger brake installation on the front.

Show us some pics
 
Mirrors don't fold in
 
My JDM Vx limited has power retract and it is totally awesome on tight trails.
I 2nd doing the BEB as soon as possible, I checked mine at 139,000kms and number 2 had a piece of bearing material missing about a quarter inch diameter. The rest only had really minor pitting.
 
Some times the motors get stuck from sitting for so long with no one using them. Mine did it the other day on w tight street when I tried them only one moved. After a little encouragement they both started working again. I find the same thing can happen to power adjusting seats.
 
Crab Sack said:
Welcome to the new obsession.
First thing you should consider doing are the BEBs, aka. rod bearings and bolts.
Second would be to check over the fluids and filters to make sure they are in good shape.
Third - Timing belt and tensioner
Fourth - External Transmission cooler, not found on HDJ81
Fifth - Valve adjust
Sixth - two thousandth on the list will find you...

Seriously it's a love hate relationship you will build with the 81.
I would only consider doing the IP modifications once you find a way to move and or cool down some more air... 3" exhaust and intercooler to keep the motor from meltdown.

You can check out my build thread in my signature for more ideas... the best mod I did was the FZJ80 bigger brake installation on the front.

Show us some pics
Click to expand...

Ok so my BEB's and bolts where already done. THey looked like they where in great shape for the mileage thats on this 81.
Timing belt and tensioner and water pump, thermostat was done. V belts done.
I will get that tranny cooler as soon as it warms up a little here or I get shop space and time at where I worked so I won't be outside. Will
get on that valve adjustment. Will need the specs for that as I have not got a 1 HTD engine manual yet.
Not going to mess with the IP pump yet but going to put a 3" or 4" SS exhaust from the turbo back on it. Have a SS MBRP muffler and 4" down
pipe sitting new in a box from a left over cummins project. Will see if I can use them.
AC system was upgraded to R134
IMG_8575.webp
Picture 010.webp
IMG_8575.webp
Picture 008.webp
IMG_8579.webp

The PO just put on a New Snorkel, ARB Bull Bar, TJM 9000lb Winch with wireless remote, 3" lift with Bilstein shocks.
New 305/75R16 Nitto Terra Grappler Tires.
 
W
vwluv10338 said:
Some times the motors get stuck from sitting for so long with no one using them. Mine did it the other day on w tight street when I tried them only one moved. After a little encouragement they both started working again. I find the same thing can happen to power adjusting seats.
Click to expand...

I guess I will just try and lube up the motor before taking them apart. My friend has the same exact HDJ81 and his mirrors fold in
just fine. I will need that option to work for the tight trails at my cabin in Perry County PA!!
 
Nice truck and good suggestions so far. I would add gauges to the list of must do's...even if maintaining stock settings: Boost, pyro and transmission temp.

IP Bosch VE, so you will be familiar if your're familiar with Dodge.

Larger exhaust is a great idea. Even bumping up the boost a few lbs without touching the IP settings is good imo. But you need gauges to know where you are at and for adjustments effect. I bet you notice a huge difference in EGT's with just a larger exhaust. Be interesting to have it all in place (gauges) before you change it. Folk who have the hydraulic A442 report that high RPM's when on long hills where you can't get or maintain lockup help keep transmission temps down. Again, you need gauges to know.

Lots of reading in this section of MUd if you search about hydraulic A442, 1HD-T, pusher pump, etc. Here are a few threads to weed through and mine info:

JDM A440F vs Non Electronic A442F

Read through this entire thread for tuning ideas when you get to that point, but in the meantime there are a few posts about the A442F hydraulic for further info: The Official 1HD-T/FT Fuel Pump Mod Tuning Thread

80 Series Transmission Oil Temp Sender Tap

HDJ81/FZJ80 Tranny Temp Gauge

Torque converter rebuild/replacement

NO FUEL PUMP ON 1991 hdj81 :/ just got a long ranger tank thought it would fit !!!

hth's
gb
 
Greg_B said:
Nice truck and good suggestions so far. I would add gauges to the list of must do's...even if maintaining stock settings: Boost, pyro and transmission temp.

IP Bosch VE, so you will be familiar if your're familiar with Dodge.

Larger exhaust is a great idea. Even bumping up the boost a few lbs without touching the IP settings is good imo. But you need gauges to know where you are at and for adjustments effect. I bet you notice a huge difference in EGT's with just a larger exhaust. Be interesting to have it all in place (gauges) before you change it. Folk who have the hydraulic A442 report that high RPM's when on long hills where you can't get or maintain lockup help keep transmission temps down. Again, you need gauges to know.

Lots of reading in this section of MUd if you search about hydraulic A442, 1HD-T, pusher pump, etc. Here are a few threads to weed through and mine info:

JDM A440F vs Non Electronic A442F

Read through this entire thread for tuning ideas when you get to that point, but in the meantime there are a few posts about the A442F hydraulic for further info: The Official 1HD-T/FT Fuel Pump Mod Tuning Thread

80 Series Transmission Oil Temp Sender Tap

HDJ81/FZJ80 Tranny Temp Gauge

Torque converter rebuild/replacement

NO FUEL PUMP ON 1991 hdj81 :/ just got a long ranger tank thought it would fit !!!

hth's
gb
Click to expand...

Thanks GB!! So what do I do to just bump the boost? This IP looks a lot different than the cummings VE IP or maybe cause it doesn't have
the TPS on top of it. So will a Denny T top hat delete work on these cruiser IP's? Sorry if these are stupid questions as I have had no time
to really sit down and research this IP. Have started reading the Official IP Mod Tuning Thread though. GOOD STUFF!!!
 
Increase boost by installing a manual boost controller and a boost gauge. I"m not sure what a Denny T top hat delete is, but I've never heard of it being used on these pumps/engines.

The firewall VIN plaque will tell which trans you've got, I'm guessing it will be an A442F, and being a '90 it would be the fully mechanical/hydraulic version as opposed to the electronic version. If that's accurate, you have a 3 speed with OD/4th, and torque converter lockup only in OD/4th gear, so heat can be an issue any time the TC isn't locked, and I would definitely add an external trans cooler, and a trans temp gauge is a good idea as well.
 
as above, have a read through the "official 1hd-t tuning thread.

The Official 1HD-T/FT Fuel Pump Mod Tuning Thread

particularly the last few pages. There's been some really good discussion and write up in there that would help you baseline the tuning on your truck.

If you want to increase performance, all the "official 1hd-t . . . " threads are a worthwhile read on a rainy weekend
 
Sweet Cruiser! It looks exactly like mine minus the lift and snorkel.
 
jpsfj60 said:
Thanks GB!! So what do I do to just bump the boost? This IP looks a lot different than the cummings VE IP or maybe cause it doesn't have
the TPS on top of it. So will a Denny T top hat delete work on these cruiser IP's? Sorry if these are stupid questions as I have had no time
to really sit down and research this IP. Have started reading the Official IP Mod Tuning Thread though. GOOD STUFF!!!
Click to expand...

I'm not sure what a Denny T top hat is either. You mentioned a 6dp and VE so with that knowledge I mentioned that the HD-T uses a VE as well. A lot of manufacturers do use the VE design and then also have their own spin on how to adapt it. I'd start by taking the time to read the links and information in this area of Mud to discover the areas that people have had to address and what they did. Let the engine breath (exhaust), moderate boost if maintaining stock turbo (folk seem to use 14psi as a basis), external cooler on the transmission and put in gauges as mentioned so you can monitor what's happening. Then you'll want to get a bigger turbo, put in an intercooler, valve body and TC upgrades...lol.

Lubegard Red makes a great ATF additive and I know folks who have experienced a 10F drop when added. Consider running synth ATF.

If you don't have a history on when the last valve set was done I would consider doing one. 1HZ and 1HDT Valve shim adjustment tutorial video

As for spares, whatever you would want to have with you for an 80 series, add in 1HD-T specific belts, filters, etc (especially fuel filters as if you run into bad fuel you want to have at least one with you).

hth's
gb


hth's
gb
 
a 4" exhaust would be very very difficult to fit, if not impossible. 3" from the turbo flange back made a massive difference on my 80, well worthwhile. Before any tweaks, I would reccomend an EGT gauge (Pyrometer) with the probe in the exhaust manifold, and a boost gauge so you know where she's at when you start.
 
AussieHJCruza said:
a 4" exhaust would be very very difficult to fit, if not impossible. 3" from the turbo flange back made a massive difference on my 80, well worthwhile.
Click to expand...

I don't think 4" all the way back would be impossible, I'm fairly sure its been done.

I have done two systems now using a 4" dump pipe back to the transfer case, then 3" from Transfer back.
to do 4" all the way, you'd need to crush the pipe to get past the transfer, or offset the transfer case mounting on the crossmember to create some room.
the next problem is getting over the chassis above the rear diff.

I think it would be doable, but would take some creativity and lots of swearing :hillbilly:
 
mudgudgeon said:
I don't think 4" all the way back would be impossible, I'm fairly sure its been done.

I have done two systems now using a 4" dump pipe back to the transfer case, then 3" from Transfer back.
to do 4" all the way, you'd need to crush the pipe to get past the transfer, or offset the transfer case mounting on the crossmember to create some room.
the next problem is getting over the chassis above the rear diff.

I think it would be doable, but would take some creativity and lots of swearing :hillbilly:
Click to expand...


You could possibly do outside chassis until the rear diff. Hmm...side-pipes?
 
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