Hilux808

Hopefully the title has caught everyone's attention. (Warning: This thread is going to be long). This thread address’s the 22RE engine with rear auxiliary heater; I don’t know the specs for the 3VZ.

If I were to ask you have you ever done a coolant flush most of you would say yes. What about changing your hoses? Probably yes to that too. It's a relatively easy job and most of us know that there are 3 hoses for the radiator on the 22RE. One on the top, one on the bottom and one under the power steering pump connecting to the curved metal tube that also connects to the bottom hose (If you don’t have power steering just look below the distributor for a curved hose). There are also 3 more on the front of the engine that I will talk about later (I've actually changed these out before too).

What if I were to ask you...how many hoses on your truck actually carries coolant in them?

If you don't know then read on.

I've had the truck for 6 years and never paid any attention to that so don't feel bad
If you don't know yourself.

The truck is a 1991 4Runner 4x4 22RE with rear auxiliary heater (so the rear passengers that I never have can keep their feet warm).

Well I found out last weekend as I wanted to change out every single hose that carries coolant for my pre-summer cooling system maintenance. I know for a fact that all the heater hoses have never been changed and since Gates recommends changing hoses every 2 - 4 years I figured I was a little over due.....at least by 14 years. Who ever changes them right?...Which is why I felt the need to write this thread; it’s time to give back to all the people who helped me out before here on YOTATECH.

Well the answer, at least for my truck (cause of the rear auxiliary heater) is 15.

That's right, 15 coolant carrying hoses, stock from the factory. You should also know this, 11 out of the 15 hoses are molded. This means you have to buy them this way because if you try to use regular hose that you cut to length it will just kink up on you. What's even more fun is that 3 of the molded hoses are only available from the dealer, at least that’s how it was for me here in Phoenix, AZ. These 3 hoses should have been gold plated for the price the dealer charged.

To do my little weekend project myself cost me $220 just in hoses. $220 in hoses!!!
Don’t forget to add in the cost of 30 hose clamps, a bottle of Prestone Super Flush, a gallon of Prestone Extended Life antifreeze, a couple gallons of distilled water and a bottle of Kool-it by Lubegard and you're now looking at what could have been my new Alpine head unit. Oh well, at least my cooling system will be ready for another hot summer, can’t go wrong with that.

The other 3 hoses at the front of the engine are for the IAC valve just below the throttle
body and a "U" shaped hose that connects the coolant temp sensor housing to the outlet that comes off the back of the water pump. This was the hardest hose to change as I had to do this all by feel. You can't see the hose and clamps once it's on.

The other hose that comes off that same outlet behind the water pump will go up to the IAC valve. It's a 90 degree molded hose and it connects to the spout on the IAC valve that is pointing downward vertically. The other IAC valve hose (coming off the IAC horizontally, pointing towards the cylinder head) will connect to the thermostat housing. This was the most expensive hose, from TOYOTA at $42.

The other 9 hoses are all heater core related. One word of advice for heater cores...never
use a pair of pliers to take the hoses off; you will crush the spouts on the heater core
since they are aluminum. Use a utility knife/box cutter to slice the hose length wise/parallel to the spout, this way you can peel the hose off the spout without applying any damaging/crushing force to it. You can also use a small flat blade screw driver in between the hose and spout to help peel the hose off once you make a slit. Be gentle as you don’t want to change the circular shape of the spout. Be very careful when using a sharp knife.

You will have two hoses coming off the fire wall, the long molded one goes to a "T" and
the other one is a short 90 degree molded hose that connects to the heater valve that’s
bolted to the firewall. Another molded hose will come off the heater valve and then to
the other "T". Two cut to length 5/8” hoses will join the "T's" to the two spouts that are near the rear of the cylinder head and one next to the exhaust manifold/heat shield. The smaller hoses on the "T's" carry coolant to the rear heater. These hoses are cut to length 5/16”. They will connect to steel lines that run under the truck but stop shortly before the rear heater. In between the lines and the rear heater are two molded hoses from TOYOTA. These sit right above the driveshaft, just after the U-joint as it exits the transfer case. Because of that I recommend putting convoluted wire loom around them to protect them from any grease being slung off by the U-joint (I picked up a bag of 5ft of 1" wire loom at Home Depot for $3). Oil and grease attack rubber hoses and weaken them over time. My old hoses were soft and swollen because of the grease/age. They were also a ¼” longer at each end compared to the new hoses and the insides were looking pretty bad too. It’s only by God’s grace that one of these didn’t blow out on me on a road trip.

Instead of saving money and not getting the hoses for the rear heater and looping the two “T’s” together with a single piece of 5/16” hose I decided to use the rear heater as it acts like another radiator since coolant is flowing through it all the time. Anything to pull more heat away from the engine helps.
I'm thinking that Gates hoses are some of the best since they are ECD (electrochemical degradation) resistant. I got all of my Gates hoses from NAPA. For more info on ECD and coolant hoses check these links out…

http://www.gates.com/brochure.cfm?br...ocation_id=541

http://www.gates.com/brochure.cfm?br...ocation_id=541

http://www.gates.com/brochure.cfm?br...cation_id=3377

For those of you that have never changed your heater hoses out I highly recommend you do this, especially if you have a 2nd generation Toyota truck/4Runner, you’re at least 13 years over due.

Here’s a complete part number listing in case you plan to do this job on your truck…

Part Numbers for (6) hoses up front - NAPA/Gates # 8095 (Upper Rad Hose - $16.19), #7546 (Lower Hose under P/S Pump – $12.99), #7877 (Lower Rad Hose - $19.99). NAPA/Gates # 10010 (Long “L” shape hose from IAC valve to water pump outlet - $10.39). TOYOTA # 16264-35030 (IAC valve to thermostat housing - $42.41). NAPA/Gates # 10400 (“U” shape hose from water pump outlet to coolant temp sensor housing - $11.77). Total = $113.74

Part Numbers for (5) heater hoses near firewall - NAPA/Gates #18992 (Long molded one from firewall to “T” - $27.70), #9815 (Short 90 degree from firewall to heater valve - $8.00), #10797 (Heater valve to 2nd “T” - $10.31). Other two hoses are cut to length 5/8” and come off each “T” and connect to outlets near head/exhaust manifold. Total for molded hoses = $46.01

Part Numbers for (4) hoses for auxiliary rear heater. (2) cut to length 5/16” that comes off the “T’s” to the steel lines. TOYOTA # 87245-89246 (Driver side from steel lines to auxiliary rear heater - $26.28), TOYOTA # 87245-89247 (Passenger side from steel lines to auxiliary rear heater - $34.05). Total for molded hoses = $60.33

Get about 2ft. of 5/16” and 5/8” hose. You’ll have some leftover but this should be enough.

Hose from radiator to over flow tank and inside overflow tank is ¼”.

Kool-It NAPA # 765-2972 - $14.18







The two skinny 5/16" hoses on the right connect to the steel lines that run under the body.


Here is what we call highway robbery...$40+ for this dinky little hose...


Here's where that hose goes...