Coolant System Refresh HDJ81 / Rear Heater Delete (1 Viewer)

[ikarus]

I apologize for starting a thread that has a million variations in the 80 series forum but the 1HD is just different enough...

I'm working on refreshing my coolant system and deleting the rear heater in my 97 HDJ81 w/1HDFT. I currently have silicone upper and lower rad hoses and the lower is leaking so I figure now is a good time to go all OEM.

I've found just about every part I need except:
- 87245-60420: The rear heater delete OEM solution for a hose running from heater valve outlet to the firewall inlet. Out of stock at Partsouq. Fingers crossed that Amayama comes through. Anyone know of another source?
- 8724560620: The hose running from the firewall outlet back to the block. I can't find this anywhere. Any ideas? Could I DIY my own?

My goal is to replace all the old rubber. Anything else I should do while I'm in there? This will be in conjunction with an intercooler install so the engine bay should be relatively open.

8724560620 is in red in these photos/diagrams.

 

[codgn]

I used 3/8ths gates hose from oreillys when I refreshed some of the rubber coolant lines on my 1HDT. I also paired it up with OEM hose clamps

 

[veiloctane]

I was thinking of doing the same but with AN coolant lines and bending my own hard lines. I just need to get some tools to make that happen.

 

[veiloctane]

I was thinking of doing the same but with AN coolant lines and bending my own hard lines. I just need to get some tools to make that happen.

This guy has a great hardline bending tutorial and also shows AN heater hose.

 

[duece71]

Threat revival!
This along with AC system refresh are going to be some of the summer projects. Any updates on the hoses? Will LCPs rear heater delete hose work for the HDJ81?

 

[OGBeno]

Threat revival!
This along with AC system refresh are going to be some of the summer projects. Any updates on the hoses? Will LCPs rear heater delete hose work for the HDJ81?

No. The diesels and 1FZ have different hose setups.

You’ll need to source the correct non-US/non-rear heater hose sets.

 

[ikarus]

Threat revival!
This along with AC system refresh are going to be some of the summer projects. Any updates on the hoses? Will LCPs rear heater delete hose work for the HDJ81?

Hi @duece71 I never did update this thread. First pic in this post shows the part numbers - I found them both through Japan4x4:

Builds - Ikarus' HDJ81 Offroad Build

Hi" super clean vehicule, great topic thank's, just a question : why did you say it's a HDJ81? I though all post 1995 1HD-FT were HDJ82 regarding the VIN number JT111TJ82xxx? can you confirm? or explain the diffrence between hdj81 and 82? and after fitting the cooler don't forget to adjust the...

forum.ih8mud.com

I recommend replacing the heater valve as well, if you can find one new:

Builds - Ikarus' HDJ81 Aussie-Style Build

Just for another perspective, I decided to leave my 1HD-FT all stock. The original plan was to remove all the "extra" vacuum lines + gadgets and convert it to Aussie-spec. I found out it's maybe not quite that simple. Toyota designed it all as a system. Just my $.02 Yeah that's a great...

forum.ih8mud.com

 

[OGBeno]

Hi @duece71

I recommend replacing the heater valve as well, if you can find one new:

Builds - Ikarus' HDJ81 Aussie-Style Build

Just for another perspective, I decided to leave my 1HD-FT all stock. The original plan was to remove all the "extra" vacuum lines + gadgets and convert it to Aussie-spec. I found out it's maybe not quite that simple. Toyota designed it all as a system. Just my $.02 Yeah that's a great...

forum.ih8mud.com

Readily available. Just got one in last week.

 

[duece71]

Thanks for the info guys. I will look into everything.

 

[Douglas S]

Readily available. Just got one in last week.

View attachment 3669433

Not the correct part for the early HDJ81 that @duece71 has - the valve for early trucks is NLA and out of stock everywhere and has been for some time.

There are aftermarket options and some other part numbers that work - HDJ81 Heater Control Valve - https://forum.ih8mud.com/threads/hdj81-heater-control-valve.827718/

 

[duece71]

Not the correct part for the early HDJ81 that @duece71 has - the valve for early trucks is NLA and out of stock everywhere and has been for some time.

There are aftermarket options and some other part numbers that work - HDJ81 Heater Control Valve - https://forum.ih8mud.com/threads/hdj81-heater-control-valve.827718/

Excellent, I will look into those options.

 

[OGBeno]

Not the correct part for the early HDJ81 that @duece71 has - the valve for early trucks is NLA and out of stock everywhere and has been for some time.

There are aftermarket options and some other part numbers that work - HDJ81 Heater Control Valve - https://forum.ih8mud.com/threads/hdj81-heater-control-valve.827718/

My bad. You are correct Douglas. I was looking at an -FT powered 80.

 

[donnerpassing]

Not the correct part for the early HDJ81 that @duece71 has - the valve for early trucks is NLA and out of stock everywhere and has been for some time.

There are aftermarket options and some other part numbers that work - HDJ81 Heater Control Valve - https://forum.ih8mud.com/threads/hdj81-heater-control-valve.827718/

I used part no 8724060140 on my 1990 Hdj81. I really wanted an Aisin/toyota made valve as the aftermarket quality kind of irks me a little bit when it comes to stuff like this. I just moved the control arm from my old valve to the new one, and screwed the new valve down on the original valve bracket and it’s worked like a charm ever since

 

[Sonofaskipper]

My bad. You are correct Douglas. I was looking at an -FT powered 80.

Man, you got me all excited for minute!

 

[HillCountryTX]

Hi @ikarus, I noticed that you have a 97 HDJ81 w/1HDFT and you were kind enough to share how you bypassed the rear heater. Thank you! To that end, I have a 1991 HDJ81 with the 1HDT (I'm guessing they have very similar coolant hose routing when it comes to the rear heater/firewall interface and coolant hose routing). Anyway, my rear heater hardlines are leaking and I am wanting to bypass the rear heater entirely by using Toyota OEM coolant hoses and clamps. Below are several photos of my HDJ81's 1HDT engine bay where the rear heater connects with the rest of the coolant piping. In your post you provided the OEM coolant hose part #'s (see the following):

1) 87245-60420
2) 87245-60620

I am having trouble determining if those hoses will allow me to remove the metal "Tee" sections both on the inlet and outlet side of things. In other words, that the hoses you listed in your original post will connect to the firewall connection, or whether they will simply connect to the existing metal "tees" I have. I would like to get rid of unnecessary connections if possible (aka get rid of the metal "tees"), but only if it makes sense.

1991 HDJ81 1HDT showing engine bay where rear heater inlet/outlet come through the firewall.

Inlet for rear heater.

Outlet for rear heater.


Looking at the Partsouq parts diagram makes it appear as if the 87245-60620 will just connect right back up to the metal "tee" and will not change anything. However, 87245-60420 will get rid of the long, bent metal "Tee" for the inlet side of things (aka just after the outlet from the heater valve). Can you, or anyone else, provide any guidance on this? I also know I will need to get some sort of cap to cap the inlet/outlet of the rear heater where it comes up by the firewall.

Thank you!

 

[ikarus]

Hi @ikarus, I noticed that you have a 97 HDJ81 w/1HDFT and you were kind enough to share how you bypassed the rear heater. Thank you! To that end, I have a 1991 HDJ81 with the 1HDT (I'm guessing they have very similar coolant hose routing when it comes to the rear heater/firewall interface and coolant hose routing). Anyway, my rear heater hardlines are leaking and I am wanting to bypass the rear heater entirely by using Toyota OEM coolant hoses and clamps. Below are several photos of my HDJ81's 1HDT engine bay where the rear heater connects with the rest of the coolant piping. In your post you provided the OEM coolant hose part #'s (see the following):

1) 87245-60420
2) 87245-60620

I am having trouble determining if those hoses will allow me to remove the metal "Tee" sections both on the inlet and outlet side of things. In other words, that the hoses you listed in your original post will connect to the firewall connection, or whether they will simply connect to the existing metal "tees" I have. I would like to get rid of unnecessary connections if possible (aka get rid of the metal "tees"), but only if it makes sense.

View attachment 3859160
1991 HDJ81 1HDT showing engine bay where rear heater inlet/outlet come through the firewall.


View attachment 3859171
Inlet for rear heater.

View attachment 3859174
Outlet for rear heater.


Looking at the Partsouq parts diagram makes it appear as if the 87245-60620 will just connect right back up to the metal "tee" and will not change anything. However, 87245-60420 will get rid of the long, bent metal "Tee" for the inlet side of things (aka just after the outlet from the heater valve). Can you, or anyone else, provide any guidance on this? I also know I will need to get some sort of cap to cap the inlet/outlet of the rear heater where it comes up by the firewall.

Thank you!

Do these pics help? this is after I got it all buttoned up. No tees

I ended up using

Toyota 87245-60420 (8724560420) HOSE, HEATER WATER, INLET D;PIPE, HEATER WATER INLET, A

Toyota 87245-60420 (8724560420) HOSE, HEATER WATER, INLET D;PIPE, HEATER WATER INLET, A. New & genuine Japanese car parts. Fast shipping. Low prices. Request a quote from Amayama Trading Co. online.

www.amayama.com

&

https://partsouq.com/en/search/all?q=87209-60360

which is an assembly and I just removed the T section, and it reached the firewall fine.

Got both from Dave @ Japan 4x4

 

[duece71]

I used the LCP delete kit on my 1990, worked great. I tore out all of the rear heater hard lines. I dodged a bullet because the 2 rubber hoses under the vehicle were very old and bulging slightly. Whew!

 

[duece71]

Here is the LCP kit.

 

[HillCountryTX]

Thank you @ikarus and @duece71, I really appreciate it. I have ordered the 87245-60420 (same as the LCP delete kit, just not Gates) that goes from the outlet of the heater valve down into the inlet of the main cab heater, as well as some clamps to go with it. The part I am not sure about is outlet side of things where @ikarus has the 87209-60360 specified (but has removed the "tee" and associated stubby portion). It feels like my hose comes from a different location on the engine and that the 87209-60360 wouldn't necessarily work. I have attached a couple photos of this as it is currently set up from the factory.

Also, what did you all use to cap off the rear heater connections near the firewall (inlet and outlet for the rear heater that is found on the firewall)? I would like to cap them off so that they are protected from debris/damage should I ever want to reconnect the system (if I can fix it). Thanks!!

 

[Greg_B]

@HillCountryTX I deleted the rear heater in my BJ74 last year and found that two of the caps (I think 1/2" but double check the HDJ80 lines) in this Dorman Bypass Cap Kit worked great to cap the rear heater lines for the exact concerns you've mentioned. The Dorman caps fit okay but I used the toyota spring clamps to ensure the caps stayed in place. I had use for a few of the other caps in the kit so the kit worked well, but I think you can get the size you need on their own.

There are comments on line of these caps degrading over time so I am keeping an eye on them and don't use for anything critcal.

hth's
gb