The hose of death thread

[Surf5557]

Does anyone know the correct order of operations for installing the upper manifold and throttle body? Last time I struggled for hours trying to line up the most accessible bolt that holds the by-pass bracket to the manifold, but I gave up on the second bolt that was further towards the "Hose from hell." Is it somehow easier to assemble these parts with the by-pass pipe already mounted?

Also, I find that the length of my hoses is causing issues. Nowhere in my 1984 Factory Manual does it list instructions for this. I'd love to just bypass the by-pass!

[timsrv]

I vaguely remember dealing with that years ago before cutting the access hole (as pictured earlier in this thread). Hasn't been an issue since. Did you cut an access hole?

If you're planning to use the van in cold temperatures (below freezing), I wouldn't disable the bypass. Doing so would prevent the air valve from working and would allow freeze-ups of the throttle body. Tim

Edit: I believe I leave that pipe assy bolted to the manifold, then cut both the bypass hoses (HOD 1 & 2). The vacuum lines are not that hard to pull off. After the manifold is out of the way, it's easy to clean-up/remove the left-over parts of hoses. Tim

[Surf5557]

Thanks Tim!
The second go around to correct the leaking bypass pipe I brazed the holes with an oxyacetylene torch and brass, then I bolted it onto the throttle body/manifold, and after that I installed the manifold. The last thing I ended up doing was connect the hoses (without the access hole) and everything is sealed up tight now for 2 weeks.
I'm convinced I fixed the leak this time, although I'm a little embarrassed that I did use some alumiseal in the coolant and it did nothing but congest my cooling system. Whoops

[Surf5557]

That last one would be a PITA to cap off with the engine installed/assembled. An alternate way for that could be to put a hose plug on the metal tube where it comes out the D/S back of the engine. If you do it that way, then you'll also need to get the bypass return line that's also part of that metal tube assy.

Frankly, I'd rather replace hoses, then you'd have heat and not need to mess with it (at least the hoses) for another ~30 years (but that's just me). Tim

In the last picture you have included a peek of the vacuum lines that go into the valve on the power steering pump. How does one correctly install those hoses when the valve can be under/over torqued and the orientation of the ports reversed? Is there indication for correct orientation on the pump valve?

[timsrv]

In the last picture you have included a peek of the vacuum lines that go into the valve on the power steering pump. How does one correctly install those hoses when the valve can be under/over torqued and the orientation of the ports reversed? Is there indication for correct orientation on the pump valve?

It doesn't matter if they're reversed. It's just an on/off valve so it doesn't matter which hose goes where.

[spacecruisers]

the pre-formed hoses on the underside of the intake (part numbers in purple) are all NLA.



I have some hose the same size but it kinks when I try to bend it at that angle. I was able to replace the one small straight piece obviously, but the bent pieces kink pretty bad.

is there a way to form it to the proper shape? or maybe use a different type of hose material thats more flexible?

[timsrv]

That really sucks............I was wondering when that was going to happen. Those are all vacuum hoses with ~1/2" ID (to direct air through the Auxiliary Air Valve). The only thing that comes to mind is to find some 1/2" ID formed heater hose with tight bends, then cut parts out of it to match what you need. When I get in a spot like that I ask the guys at my local Napa to let me look through their inventory. There's also some weird shapes and bends available at the Dorman HELP! rack.

Then there's brass nipple elbows pushed onto straight hose. Another option is Unicoils. Gates makes devices called "Unicoils" that you put over straight hoses. You get one that fits the OD of the hose, then you can bend sharply and it prevents kinking. They work, but I'm not crazy about them as they make the hoses heavy and clunky. As these vans get older and parts get harder to find, I suspect there will be a lot more of this type thing we're forced to do to keep them on the road. Good luck. Tim

[originalkwyjibo]

That really sucks as I was getting ready to rebuild a spare engine and replace all that stuff. I went through this when I did my head gasket 5 years ago. I tried my best to avoid the dealer but ran in to problem after problem with aftermarket hoses. The issue was the diameter. They actually are not 1/2 inch but 12 mm which requires a clamp to seal and is still not ideal. From what I remember there was not enough room on some of the air valve connections to install a clamp. I had the same issue with coolant hoses and the local industrial hose supplier told me this was common on Toyota, Mercedes, and a few others that chose to use metric sizes. The solution was to either stretch on the next size down or clamp down the next size up. I ordered all that was available form the dealer and compromised on the rest. I used a unicoil for the small angled hoses at the rear heater core as they were NLA at that time but like Tim said it makes for a bulky hose and may not fit for the air valve application. Two years ago when I tried to find a unicoil for my Subaru most parts store counter persons looked at me like I was a moron and said," A uni-what?". The guy that finally knew what I was talking about said they quit making them but I've still seen them online just not on the local parts store counter.

[llamavan]

[...] problem after problem with aftermarket hoses. The issue was the diameter. They actually are not 1/2 inch but 12 mm which requires a clamp to seal and is still not ideal.

And this is why I had to spend eight hours on my back on a cold cement floor (and cussing almost the entire time) to replace a leaking HOD not all that long after the head job (by someone else). There's no substitute for OEM hose, especially in any hard-to-access locations!

Gwen

[originalkwyjibo]

They actually are not 1/2 inch but 12 mm which requires a clamp to seal and is still not ideal.

I was incorrect on the size. Factory is 14mm not 12mm. Hope I didn't cause anyone confusion.

[Jbbishop2]

Just another Hose o' Death access panel job, and huge thanks to the detailed original post and all the help that was posted after. I'm replacing the hose with the only thing the local CarQuest auto store had that will fit, SAE 30R7 fuel line hose. It's rated to 50 PSI working, 250 psi burst, 275 degrees F, and is nitrile-lined. The silicone heater hose sounds better, but a hose in the hand...

[AD2101]

Good luck man. I nearly got burned by the previous owner cheaping out and using 50 psi fuel hose rather than proper heater hose for a hose of death replacement. It worked for a couple of years but split in half at literally the most inopportune time.

I'm sure you could rock it for a while but I'd hope you get some proper hose for it. It'll be a quick replacement since you've already done all the leg work.

[Jbbishop2]

Good luck man. I nearly got burned by the previous owner cheaping out and using 50 psi fuel hose rather than proper heater hose for a hose of death replacement. It worked for a couple of years but split in half at literally the most inopportune time.

I'm sure you could rock it for a while but I'd hope you get some proper hose for it. It'll be a quick replacement since you've already done all the leg work.

It's a valid point, and I'm going to pick up the Toyota 99556-10200 (or 99556-10300, as Tim recommended, long enough to make two replacements) as soon as possible. The original seems too have lasted 29+ years, that's good enough for me. Thanks for reinforcing the urge to get the right part.

[armorrell]

I'll be doing this change out soon and post another video of the process once I get into it. Thanks so much TIM for all the reference points and education. It's definitely invaluable!

[ShapeShifter]

I'll be doing this change out soon and post another video of the process once I get into it. Thanks so much TIM for all the reference points and education. It's definitely invaluable!

Looking forward to it. Ramjetalpha1

[Kombi]

It would appear that it is prudent for a new owner who is positive that nothing has been done in 15 years to a van to flush, then replace all water hoses, and the thermostat? And that the OEM hoses are worth the premium. Time to get a parts list together. Any particular antifreeze? Will the antifreeze sold for Asian cars work? Or is that for aluminum engines?

[Kombi]

For those that need preformed tight bend vacuum hoses that are NLA 90 degree plastic angles are available from a variety of sources.
https://www.google.com/search?client...30.JwLHLHVeh0c

Hydroponic supply stores might be a source. I think Granger or a heating supply Jobber. Some heating systems are vacuum controlled. A brake tubing bender might let you do the angle in steel.

[JDM VANMAN]

The other day after driving the van on some morning errands I noticed some smoke coming out from underneath the driver side of the van, I opened the door and could hear a drip and burn off with smoke, because of where it was located I thought for sure it was the Hose of Death!!


Contacted my MasterTech and informed him of what was happening and the following day Sunday afternoon I drove it over to his house for a quick diagnosis. He jacked up the van and rolled under with the creeper for inspection and found not only that the Heater circulation molded hose was dripping but the Hose Of Death had developed elephantitis (fully expanded) unfortunately I couldn’t get a picture of that from laying on the creeper.


Thank you Tim for documenting this thread, I sent him the link for review as an easier option for the repair and he loved it.


Leaking Heater Circulation Molded Hose/Repaired with molded hose to route away from the manifold.














Hose of Death ready to blow








Cut access hole and replace with the Gates Heater Hose, new clamps, heater foil wrap and seal back up













Thank you Tim

JDM

[Kombi]

Has malleable copper tubing been tried? this seems to be a cheap and easy to bend tubing https://www.youtube.com/watch?v=oWP_zEKLvyc

[Jbbishop2]

I haven't tried copper tubing for the HoD, but this is a nice method, thanks for the link!