PHH - is there an ULTIMATE solution?

Flagster

Expedition Leader
break it...!

The time consuming part for me was removing the bottom bolt on the metal tube...I gave up after 10 different wrenches (including the gear wrenches recommended on MUD) and two hours later ended up breaking out the metal tube by wiggling it back and forth and fatiguing the bolt bracket.
After that it is really a 15 min procedure slipping the bypass over and routing up through the engine compartment. Make your connections and refill the small bit of coolant that leaked out.
IMO You can do in a couple hours 1. If you have dwarf hands to quickly remove the lower bolt... or 2. If you just break the metal tube from the start...
I also just used stock hose with an outer sleeve...really easy to change now so no worries on length of service.
 

MarcFJ60

Adventurer
Removing the starter makes the job easier. It's also a good time to replace the starter contacts. As long as you replace it one way or another, I don't think it matters. The only wrong answer is to leave it and hope for the best.
 

Skrewball

Observer
Not that this hasn't been argued over and over, but don't we buy Toyota Land Cruisers for a reason?

How many miles did the stock hose last? Usually at least 150K. I have replaced stock ones with 300K. Mine went at 170K.

What is more likely to burst/split/chafe/rupture, steel or rubber? Toyota designed it to use steel for most of the routing for a reason.

If i replace it with a Toyota PHH, how long will it last? It should last about another 150K miles at least.

I replace these all the time, so i have some tips that make it possible for me to be done in an hour.

Remove the top section of the trans dipstick tube.
leave the starter in place.
be careful of the knock sensor.
a long 3/8 ratchet with a pivot head and a normal shallow 12mm socket will remove the lower bolt.
quality clamps that you don't overtighten.
don't put the lower bolt back in.

all just my $.02
 

VanGo

Explorer
I would suggest that there are several good solutions for replacing the PHH, and recognize that modifying this area to be a good idea, given it's history as a point of failure. Failure based on too many variables to list, but a couple variables that do seem to rise to the top are lack of preventative maintenance (PM) and simply "vehicle awareness". Knowing your vehicle's PM schedule and recognizing visual failure ques are important to any vehicle performance. Personally, I use a Gates kit with Breeze constant torque clamps, bypassing the rear heater as a solution to two proven areas of failure: PHH and the rear heater lines. Does this make my personal choice for modding the PHH the "ultimate solution" of course not. I have simply used the information available through personal research and hands on experience to come to a personal conclusion to address the PHH and my concerns. HTH.
 

Schattenjager

Expedition Leader
Not that this hasn't been argued over and over, but don't we buy Toyota Land Cruisers for a reason?

How many miles did the stock hose last? Usually at least 150K. I have replaced stock ones with 300K. Mine went at 170K.

What is more likely to burst/split/chafe/rupture, steel or rubber? Toyota designed it to use steel for most of the routing for a reason.

If i replace it with a Toyota PHH, how long will it last? It should last about another 150K miles at least.

Thanks for the tips!

However, this falls in the camp of 'why modify anything from the factory.' Well, at least to some degree it does. The PHH is probably not a problem for right hand drive cars to service. They may have simply over estimated the service life of the hose or more likely it never came to their attention as a maintenance item for the warranty period.

Not addressing this is, as a previous poster mentioned, the only wrong solution. I am going to soon drive from Anchorage to Colorado via Washington in late fall / early winter and do not want to think of doing this job on the side of the road with temps in the teens. With 150K just turning on the rig, it is a possibility, yes? The bypass, while not as elegant as the factory hose, makes the most sense to me. Simple, effective, easily inspect-able and serviceable. All the things the factory PHH is not. New parts can fail right out of the box as we have all likely experienced. Such a tedious job related to a critical potential failure should not, in my opinion, leave an upgrade unused in the name of factory specs.

I hope to tackle this tomorrow.
 

a.mus.ed

Explorer
Mine failed at ~130k miles, and took me 4.5 hours to fix (big hands/wrists...). I expect my bypass will take me roughly 15 minutes to replace. So....

1300000/((4.5*60)/15)=7222.22

My bypass can fail every 7221 miles and I'll still save time over replacing that damn stock PHH.:shakin:
 

Schattenjager

Expedition Leader
Did the by-pass - pretty easy job

This by-pass project was not the night mare I spent half the morning psyching myself up for. I can imagine trying to replace the PHH to factory specs being a major pain, however.

38ef9f65.jpg


Basically this and adding an oil pan heater and sheepskin seat covers took less than three hours. Not what I expected.

Pictures follow, but I will outline the steps for ExPO member to spare a trip to mud. Which is a real favor, btw. :sombrero:

1) Jacked / used stands for the driver front, removed the wheel and only the rear-most fender skirt. I used a door panel tool and everything stayed in tact for easy reassembly. You can look up toward the rear intake runner and see the offending hose taunting you. I then loosened the PHH clamp on the head side of the hose only.
9c4e3cf2.jpg

d2121f19.jpg


2) Removed the top bolt supporting the metal pipe and removed the associated heater valve hose clamp and removed the hose from the valve.
8921da87.jpg


3) Did the wiggle thing. Bent the bracket that the top bolt was removed from in order to get a wider throw and, with the bottom hose clamp loose but the phh still in place, I rocked the metal pipe back and forth and to and fro for about 10 minutes. The bottom, impossible to reach bracket acts a fulcrum and will cleanly brake away, freeing the assembly for removal. Stay with it, it's a short time well spent. This photo shows the heater valve hose spun 180 around to make a handle for rocking the tube free.
f3d48511.jpg


4) pulled the PHH free of the head. Have a bucket ready as you will loose some juice here. I am a pet guy, so i used the cotton paint tarp that is treated on one side. Soaked up the splash off and did not get any on the floor!
fc8cd349.jpg


5) now the assembly is free, it just a matter of getting it out of your way via fishing it through the tight, limited room available. I pulled it up and out.

6) the silicon hose is quite flexible yet sturdy. A BIG HELP was soaking the by pass hose in really hot water for 10 minutes. This allowed it soften and expand a little and sliding on the head pipe was made pretty simple. I struggled for a bit before doing this. It makes a vast difference in your favor to heat it up with water first.

7) routed it around the break master cylinder and hooked it up to the heater valve. Tightened the clams, refilled the radiator with the coolant in the bucket (going to flush it soon, but later) and started it up for a test. It came up to normal temp but the heater output was only warm. After several more minutes, the heat came back up to normal too - the delay likely due to air in the system.

I only used a ratcheted boxed end wrench for the hose clamps and the top bolt and the door panel tool for the fender skirt.

This job proved to be entirely unnecessary. The PHH on the truck looked very new and had worm drive clamps vs. the factory cotter pin arraignment. Oh well, such is life. I am very happy with the peace of mind and the ability to very easily service or repair this vs the factory PHH. Time and money well spent indeed.

Afterward I tended to the oil pan heater and then the sheep skin covers. I had budgeted an extra three hours for the project and was pleasantly surprised how easily everything came together. So far, anyway...
:snorkel:

Get your kit here!
 
Last edited:

Forum statistics

Threads
185,828
Messages
2,878,632
Members
225,393
Latest member
jgrillz94
Top