Suggestions for 1HDT Coolant flush

[DBWood]

Hey Gang,

Going to install an inline heater in my lower rad hose in the next week or so.
Was thinking that it would be a good time to do a coolant flush/fresh refill. (I have an intermittent heat issue that I have been chasing for a bit). My Coolant looks OK, but, maybe the system needs a good clean out.

Anyone have a suggestion for a Coolant Flush Product?

Thanks, Merry Christmas.

Doug

 

[roscoFJ73]

I dont believe a home mechanic can do a lot to flush the coolant system. My local radiator shop will pump some high pressure water through the system with the radiator removed to try and stir up any sediment sitting at the bottom.
On top of that they will remove the upper and lower tank and rod the cores if you want.
You might want to consider the rodding as a solution to your heat issue.
The other thing that sometimes causes overheating is a weak fan clutch.

Some people add a weak solution of hydrochoric acid to help remove any crud,but Im not a fan of that.

I would just fill up and drain with clean water to get the old coolant out and then refill with new Toyota red coolant.
Ive been using Toyota red for 6 years in my HZJ75 and the coolant stays as clean as the day it was put in,till I do its next 2 yearly change .
I also believe in replacing radiator caps every 2 years ,rather than waiting for them to fail,by which time they have already begun to let air into the system to start the corrosion practice.

 

[wongtsenhin]

I dont believe a home mechanic can do a lot to flush the coolant system. My local radiator shop will pump some high pressure water through the system with the radiator removed to try and stir up any sediment sitting at the bottom.
On top of that they will remove the upper and lower tank and rod the cores if you want.
You might want to consider the rodding as a solution to your heat issue.
The other thing that sometimes causes overheating is a weak fan clutch.

Some people add a weak solution of hydrochoric acid to help remove any crud,but Im not a fan of that.

I would just fill up and drain with clean water to get the old coolant out and then refill with new Toyota red coolant.
Ive been using Toyota red for 6 years in my HZJ75 and the coolant stays as clean as the day it was put in,till I do its next 2 yearly change .
I also believe in replacing radiator caps every 2 years ,rather than waiting for them to fail,by which time they have already begun to let air into the system to start the corrosion practice.

How many can of coolant did you fill in for 1HZ/D?

 

[gerg]

When I replaced my rad I wanted to flush the system as well so... I made this out of some screen door mesh I got from the hardware store and folded it into a cone.




I then put it in the intake of my radiator to catch all of the crap.



I used a strong rad flush solution and followed the directions. Most of these things are acid to dissolve the minerals that form inside.

I turned my heaters to cold to stop circulation to them (or they will become your filter trap) and high idled my engine to get it nice and hot to open the thermostat. You could just remove if you wanted.

This is just a protion of what the rad trap caught. That white thingy is a big piece of silicone.


Some of the larger pieces are about half the size of a pea. There was tons of crap in there. After a few clean outs of the filter, and there was no more dirt, I opened the heaters and let it circulate. I then back flushed my heater cores with water and compressed air (10psi) and got alot more dirt out. I used 2 plastic jugs to catch the return fluid. The heaters have 2 inlet hoses and 1 return so its actually easier to do than it sounds, its just a messy job. After using the compressed air, I hooked up a pump I had laying around for pumping water in an RV and finished back flushing till it was clean. You could use one of those cheapo pumps that attach to a drill from harbor freight or something. Heaters work awesome now. Guess they were quite plugged.

On a side note, just so no one tries to sue me for horrible burns to their face and genitals. Please don't undo rad hoses or open your rad cap when your system is hot. And... if you just said "why", please dont try this rad flush thing at all.

 

[roscoFJ73]

How many can of coolant did you fill in for 1HZ/D?

I think it takes about 10 litres all up. So you need 5 litres( 4+1) of toyota red and add 5 litre of water.You can use tap water but distilled is better and supposedly gives you a longer service life.

 

[gerg]

Distilled water is much better. It has all of the minerals removed that form some of the deposits that plug up radiators, like calcium and such.

 

[Cruisin']

Hey DBWood, if you're chasing an intermittent cooling issue, definitely change the rad cap. I had one fail and it was allowing coolant to escape (into the expansion tank), but would let air back in via the cracked rubber seal. The el-cheapo one that I put in would still let a bit of air back in when cooling, and it took a genuine Toyota cap to finally fix the problem.

HTH

 

[DBWood]

Hey Guys,

Thanks for all the input.

Gerg, you are very thorough!

I installed the heater last night (which reminds me, I should go plug it in...)
I put in a new solution of coolant/distilled water. I think I will run that for a couple days, and then drain and see what it looks like. If it is clean, I will get the Toyota Red. If it is not, I will likely end up using Gerg's system.
I put a new rad cap on about a year ago, but I think I will try a new one. Can't hurt for the cost of it.

Thanks again, Happy New Year.

Doug