Coolant flush / Radiator, Hoses, Thermostat and Heater T all-in-one (1 Viewer)

[usedname]

Hi folks, this is my first step after oil change in baselining, and the tech had mentioned a small coolant leak (didn't say where) so I figured I'd just replace the radiator and thermostat. Timing belt was done 4y/30k miles ago.

I read about 30 different radiator replacement and coolant flush threads and saved a bunch of directions/tips/photographs from different posters. I apologize for not attributing the photos! I just want to be sure I have a good sense of what I'm doing by getting some feedback from you guys.

The biggest question is, do I replace the radiator and thermostat BEFORE or AFTER flush? I assume AFTER. Just thinking that I don't want old crud getting into new parts.


Drain:
1. Park uphill
2. Turn all heaters on before shutting off engine (I assume I can't really move the car between now and when I'm done with the flush and replacement)
3. Take off lower engine cover to get at engine block drains (but center bolt only needs to be loosened), take off upper engine cover to get at heater Ts
4. Open up radiator cap
5. Open radiator drain

6. Open DS/PS engine block drains

7. Replace heater Ts (these are hardly going to get blocked up by old crud)


Flush:
1. Close drains
2. Fill reservoir with distilled water
3. Keep radiator cap open?
4. Start engine
5. Keep refilling reservoir or radiator? Turn off to drain? Or can I drain while I'm flushing?
6. Drain using radiator drain? Or lower hose?


Replace:
1. Once the drained fluid looks pretty much like water, disconnect upper and lower hoses
2. Disconnect A/T hoses (do I clamp these before pulling them off? I think I saw someone stuck the butt of a toothbrush in the ends of each hose?)
3. Remove reservoir?
4. Remove hoses and radiator assembly but not according to FSM - no need to remove fan/pulley/belt, but maybe remove battery?
5. Remove radiator side supports from old radiator to fit on to new radiator
6. Take off top foam from old radiator to put on new radiator, OR replace with some kind of weatherseal/closed cell foam
7. Replace thermostat and gasket
8. Replace upper/lower hoses
9. Replace radiator assembly


Refill:
1. Fill reservoir and radiator with new coolant?
2. Replace with new radiator cap
3. Burp system, keep filling reservoir
Done?


Stuff I'll need:
Drain pans, funnels
5/16" ID PVC piping for engine block drains
10 mm socket (and I'm guessing other metric sockets)
1/4" ratchet
extensions
several gallons of distilled water
4 gallons of Valvoline Zerex


Another Q: What height should I have the AHC? I think L would be helpful for the heater Ts, but maybe H would be helpful for everything else, especially if I want to try to get at the PS engine block drain from under the wheel well as someone posted:

 

[2001LC]

You have some procedural errors. Before we go there. Find the leak, this is key If the coolant system has Toyota LL (red) which I'd not use anything else in a 02. Leak will leave red/pink crusty trial or a puddle.

 

[namsag]

I have a question about that engine block drain plug - is that a little pipe that you can slip a hose on to make draining the block less messy? Do you loosen the brown plug or the whole silver one?

 

[2001LC]

Yes, just slip a hose on silver tube. Then loosen the brass 10mm drain plug. Sometimes they're plugged from inside block. I've had great luck just blow about 10 PSI back into block via my drain hose to get flowing when plugged.

 

[namsag]

Thank you sir that job is coming up soon for me.

 

[usedname]

You have some procedural errors. Before we go there. Find the leak, this is key If the coolant system has Toyota LL (red) which I'd not use anything else in a 02. Leak will leave red/pink crusty trial or a puddle.

Yep I got the red stuff. Not sure about where, the only place I can see without really getting in there is both ends of the upper hose:

 

[usedname]

Engine side.

What do you think?

 

[boca1]

I start with just the upper radiator hose from Mr T, that is not OEM

 

[2001LC]

View attachment 2123318

Engine side.

What do you think?

Good job!

I do prefer all factory hoses and clamps.

The fact you've replacement hose & clamp (non OEM) and I can't see any foam in front of radiator. Tells me this is a newer aftermarket radiator.

Do you have and active leak? Wet spot just sitting or after running engine at operating temp, are active leaks.
If loosing coolant (needing to add), this would indicate an active leak.

To check level, do a topping procedure.
Top radiator with distill (DS) water after an 8 hour cool down. Vehicle must be level or front slightly higher than rear is best. Remove rad cap and top, note how much if any is added. Bring reservoir to max line with OAT (outside air temp) of about ~80F, at same time with DS water. I assumes you're not in freezing weather. By adding more than a qts of DS water, we're changing the ideal 50/50 mix. But no matter, you'll be flushing soon. For now we're just inspecting and building parts list.

Run engine (best just drive) at 2K RPM 5 minutes after reaching normal operating temp, with both front and rear heaters on full hot. You'll need HVAC fan on, to set temp to HOT. Note: If either heater in cabin, is not blowing very hot, you've likely an air bubble in a heater core. Rear heater blows from rear base of front center console.

Check again next morning to see if all air out, by repeating topping procedure. Keep checking each morning until system will not take more DS water. If more than three or four mornings of topping and still you need to top/add. You may have an leak active leak. A leak this active is easy to spot, but most are just weeps.

Note: If OAT 32F, coolant level in reservoir will be lower. With a 90F OAT coolant level will be higher in reservoir. This is due to coolants expanding, as it's very sensitive to temperature. Radiator will always be full, provided coolant system operating and peak performance.

Note: When you remove rad cap, if as full as it should be. You may get some coolant spillage on top of radiator soak it up. Work to not spill DS water or coolant, soak up what you do. Otherwise you may see wet spots to you created.

Note: So often these systems, after being worked on, are not properly topped. So just being low at the moment you first look, is only clue that needs verifying.

Here is what I'd do:

I'll inspect for leaks before and after topping by:

Remove skid plates 1# & #2 and engine cover This give you better view of of lower & upper parts of engine and radiator
I inspect the front & back of radiator. Pay special attention to the seams where plastic top and bottom meet the metal.

In your 3rd picture I see 2 of the 3 small hoses from oil cooler. There is one more on the front attached to the oil cooler on same pipe. You need to check every inch and fitting of those. There is also one on the back of oil cooler/filter housing that goes to block near engine mounts. This one is very hard to see. But if leaking, "which I doubt" it is will leave a trial on oil pan, likely going to bottom rear of engine and you'd likely see clues in #2 engine skid (Under cover) staining

The upper radiator hoses you pictured at engine. Is connected to the water joint front. Check both end on engine where it connect to engine for leaks. Check water joint rear at both ends. DS heater Tee connects to the rear water joint by way of a hose connect to a pipe going into water joint rear. Look it over carefully. Note: never put and pressure on that pipe from rear water joint by pulling on it anyway especial not side pressure.

Inspect heater Tees and hoses at back of engine going to fire wall.

If no sign that heater Tees have been replaced or not in history of vehicle add 2 of those too parts list.
Inspect lower rad hose at bottom of rad. Check at top where it connect to thermostat housing and all around area going to engine (water pump)

Inspect front and rear weep holes of engine at bottom of engine.

Drive bring to operating temp and inspect for active leaks. These are more than just the red dry crusty, they're wet.

If you don't find any active leaks, but coolant level keeps dropping. There are more advance places to look we can talk about in a week or two after topping, inspecting, watching. Also, always be aware of the sweet smell of coolant. Just a puff now and them may be overflow hole a top of reservoir cap. More is indicative of an active leak. keep eye on temp gauge. It should be near center or above most all times.

 

[usedname]

...

Thank you sir. I will top off with distilled water, mark the point w masking tape, and then check/recheck.

I don't think there are any active leaks, going back over the report from the tech, it appears they only marked that there seemed to be a history of a leak, and they thought it might have been at the tank or at the hose which made it appear close to the tank. I'm fairly sure they are referring to the same spot I photographed above. I will definitely take off the covers to check for any further leaks, but coolant level has been stable.

I'll clean the red crust that is there to make sure, but it seems too scant, I doubt it is leaking now. If there are no leaks, and a closer inspection of the radiator doesn't show any significant browning/deterioration, then I guess I would only replace heater Ts and do a flush? Do I really need to switch out the upper hose if there are no further leaks? Should I add foam around the radiator?

 

[2001LC]

Your call, on upper hose & clamps, if not leaking. Also make sure it's not rubbing the engine cover. Me, I'm big on OEM for most parts and feel Toyota has the best hoses, clamps and seals. But no reason to waste money if not and issue.

Use great care doing the heater tees. So many put undue pressure on pipe coming up from DS (driver side) of engine.

So I've given you topping procedure. It's very important. Once you have that down and check it hold fluid. We can then move to flushing.

Note: Some here will say it's normal to loose some coolant over time, I do not agree. No fluid should change level due to leaks IMHO. 100 series don't even use oil in 5K miles.

 

[JunkCrzr89]

Use great care doing the heater tees. So many put undue pressure on pipe coming up from DS (driver side) of engine.

Throw my $0.02 in on what @2001LC said above: Just cut vertically along that hose between pipe and T, and replace with new hose. That one section of OEM hose is cheap (<$20). Cutting the old one off should keep you from messing up the pipe/outlet gasket and causing another leak that’s arguably much more difficult to get to.

 

[auchief]

I'm having a real hard time opening the passenger side drain on my 2003 LX. I can't get to it with a socket due to a bracket that's in front of it. I can't get it to budge with my combo wrench.


Any tips? I'm close to just going ahead with the flush without draining that side.

 

[JunkCrzr89]

I'm having a real hard time opening the passenger side drain on my 2003 LX. I can't get to it with a socket due to a bracket that's in front of it. I can't get it to budge with my combo wrench.


Any tips? I'm close to just going ahead with the flush without draining that side.

IIRC, I used a 1/4”-drive 10mm socket on a swivel joint and a couple of extensions.

 

[2001LC]

2003 up, I've found my go tool to a be a 10MM flare nut crows foot. I use 3/8" breaker bar with about 20" of extension. Tuck extension up against control arm next to outside of T -bar bracket IIRC. It works good if drain plug not frozen in. If frozen, and I must get power in to turning plug. I than use a 6 point 10mm socket. To get socket on, transmission cooler line bracket must be removed.

98-02 are so much easier.

Have really good lighting, really helps here.