Cleaned my cooling system: the full scoop...

[Rich]

B, Yeah, Penray's writing could have been clearer. Iin the last paragraph they refer to both distilled and deionized water. I'm sure they know the difference. They don't dis-recommend distilled, and they do recommend deionized. I didn't interpret what they said to mean "don't used distilled". I did interpret what they said to indicate that they have no concern that using deionized water to dilute concentrated coolant is a bad thing to do.

Myself, I use city water to flush and distilled water to dilute.

 

[tiorio]

Thought I'd revive this thread to say thanks for the detailed wrtie-up and esp. the materials list. I did my 80 and a buddys 62, flushed and backflushed the heaters, block, and radiator. Being able to go grab the adapters and PVC to fit the hoses in one trip saved a ton of time. I went SIGNIFICANTLY simpler with the adapters though, no pressure gauges etc. and skipped adding the T in the colling circuit.

His 62 had a new radiator in 2 years ago, and he hadn't flushed since then. There was a surprising amount of sludge. A reminder that this should proabably be done every year as good PM!

My 80 had been neglected for... a while, and the coolant looked like brown mud. Heater, block, and rad all had significant amounts of sludge come out when backflushed. I used the Prestone stuff but don't have a data point as I put it in before I backflushed. Replaced thermostat while I was in there and filled with distilled and Toyota red coolant.

Thanks again Eric!

 

[Snowtire]

Thanks for the writeup.

On Saturday I did mine on the new (for us) '97. There was orange coolant in the overflow tank and green in the radiator, so I figured it was good pm to flush it all out. I lived through and repaired a Vanagon head gasket failure caused by bad antifreeze, and I am happy not to repeat that.

It was easier than I thought, and it required none of the PVC stuff. Here's what I did:

00) Turn on the car heater, then turn off car.
0) Let the engine cool for a few hours
1) Opened radiator cap.
2) Removed the belly pan under the radiator. Four bolts, I think 11mm. Note that the belly pan didn't come out, just moved back so I could reach the radiator petcock
3) Got 5-gallon bucket ready under the radiator.
4) Removed white plastic petcock with fingers. Drained the radiator
5) Removed 14mm brass drain bolt from block. This was accessible by "parting the curtains" just behind the front axle. I didn't need to remove the tire as some have done. My truck is stock and not lifted. I started with about 2 ft. of 3/8" extension drive on the 14mm bolt. I couldn't get it to budge given the awkward position. I crawled underneath and got a 6 or 8 inch extension on it and got it to break loose. Removed bolt and let that drain into a bucket.
6) Using pliers, loosened clamp on the heater hose high on the passenger side of the engine where it connects to the metal tube that runs the length of the engine fore/aft on that side.
7) The rubber of the tube was fused to the metal. Using pliers, I grabbed the heater hose where it fits over the metal tube and worked it by rotating it. This broke the rubber free from the metal. Pulled the rubber heater hose free from the metal tube.
8) Brought garden hose over and:
9) Immersed it in the overflow tank an flushed that.
10) Poured water into the radiator through the cap opening at the top.
11) Pushed the running hose up against the rubber heater hose and used my hand to form a seal. It wasn't the best seal, but it was a hot day and so I got sprayed a bit. But it built up enough pressure to start pushing fluid out down below.
12) Did the same on the metal tube from which the heater hose was disconnected.
13) Went around repeating steps 9-12 for 15 minutes. Did I mention it was a hot day and I didn't mind getting a little wet?
14) Let everything fully drain.
15) Poured a gallon of distilled water into the radiator and heater hose (turned upwards and pouring slowly). Let it drain.
16) Siphoned the water out of the overflow tank using its hose.
17) Closed up radiator petcock and brass block bolt.
18) Bolted up bellypan (might want to wait on this until you are sure there are no leaks)
19) Attach (but don't reclamp) heater hose
19) Poured 1.5 gallon of antifreeze (Dextron Orange) into radiator.
20) Poured about 1.5 gallon of distilled water into radiator.
21) Turned on motor and watched bubbles come up at the radiator cap hole
22) Had friend rev (for about 20 seconds) it while I poured to replace as level went down.
23) Bravely disconnected heater hose while motor running to burp the system. I don't know if air bubbles get trapped up in the high spots there.
24) Clamped hose.
25) Filled overflow tank with distilled water and a bit of antifreeze.
26) Put cap on. Drove for a while watching gauge closely.
27) Felt good!

It was a 2 hour job, start to finish. No specialized tools. Could do it in one hour next time. Thanks for the help!

 

[gotmud]

Holy thread revival!

Sounds like you did a thorough job.

Don't be surprised if you catch some flak for using Prestone Orange vs. Toyota Red.

 

[Snowtire]

Yep, I know. I just went with the idea that new and clean is better than nothing. Orange was already in there.

 

[Kaoscruizer]

Thanks Snowtire! .. much appreciated. I wanted a method that didn't take all day. Your method looks sound. Gonna give it a go next week .. with OEM red!

 

[gbell210]

After draining the system from radiator and block and refilling with tap water,
if I only performed my flush from this location of the Prestone T (I was able to squeeze the 3/4" T into this location) will I get a good flush? (I am replacing my radiator and flushing with the old one)

I started the water hose running first w/engine cold and not running, and then with engine running and both heaters on full. It idled for at least 5min with the radiator cap off and water eventually came out clear for several minutes. One thing that was odd, but may be normal, but during the first minute of the engine running, the engine surged a few times.
Is this due to the system purging the air and/or the thermostat opening and closing?
Thanks, BTW great detailed write-up.

photo4
this is the final arrangement with the Prestone Tee to hose adapter in the heaters outlet hose. Easy for flushing the block. Note for those of you up North, this will obstruct the flow a tad so may reduce the flow through the heaters. But I'm still cranking out air at 150F through the dash, so that'd be enough for California I think...
Also: Warning! if that thing ever leaks seriously, you may be out an engine, so caution is suggested.

 

[superdeeda]

any chance the block plug location is the same for a 91 fj80? im still looking.. Thanks

 

[TXBruiser]

Is disconnecting the Heater Hose on step 23 absolutley nessesary, or was this done becasue you were unsure? I guess what i am asking is will the system burp itself without this step?

Great post by the way!!!! thanks

 

[084runnerltd]

Bringing this thread back to life with a quick question.

I have no access to pressured water/hose.....dont ask.

Anyway, everything is drained now, coolant came out clean. If I flush several times with water, will this still get most of containmints out?? How important is the back flush?? I guess I really don't have any other options, but with this information, would you guys recommend any deviation in the process??

Thanks.

 

[johnalex]

Just a quick thank-you to all of you who posted on this over the years. Some of us are still getting useful data after all this time.

Now to figure out how to get rid of the rear heater circuit.

 

[Taco crawler]

So do u have to burp the system when u flush it or will the air get out by itself through the radatior ?
Does anyone have a pic of block bolt drain ? I have a 97 needing todo a good flush

 

[aclos3]

I did this originally by removing the upper heater hose, as referenced about 10 years ago in this thread, but more recently I did the flush without removing the upper heater hose. I don't believe I got as much coolant out the second time. Also, after filling with coolant mix and taking it for a drive around the block, the temperature rose rapidly. After returning and adding a little more coolant to the reservoir about 5 times, it finally glugged (I could hear it from inside the truck) and temps went back to normal. I think I may have gotten it to glug by doing some hard stops, quick accelerations and rapid sawing of the steering wheel to induce roll.

Bottom line, remove that upper heater hose. It takes little time and insures a complete job.

 

[Taco crawler]

Will do thanks

 

[SmokingRocks]

where is the drain plug on the block??

 

[NLXTACY]

where is the drain plug on the block??

Driver's side. Look thru the wheel well and you'll see the bolt. It's a bolt by itself with nothing attached to it.

 

[SmokingRocks]

Thanks @NLXTACY. Got her all buttoned up now she is idling at op temp looks good but the main heater is not blowing hot air? Do I just need to wait longer for the air to bleed out?

I can see the heater proportioning valve open and the lines there feel hot hot. did I miss a step?

the rear heater is working...??

Nevermind. I just needed to be more patient.

 

[grizzlygibbs]

You usually need to burp the system by parking on an incline, allowing the heat to run and taking off the rad cap. Make sure the system is not too hot as it can spray out everywhere.

 

[e9999]

dang, 12 years ago already? sheesh...

 

[RFB]

old post still works like a champ. Thanks Guys