Rusty coolant?

[HawkGunner]

It doesn't smell like exhaust, and isn't all creamy and foamy like it had oil in it. Truck isn't blowing white smoke. Oil in oil pan looks clean, same as under the valve cover. Truck doesn't overheat after running 60mph-ish for half an hour or so.

Cools off quickly.

I put some flush in the radiator a while back, flushed and changed it. Maybe I didn't flush it very good?

Does this look terrible?

 

[C6H12O6]

I'm sure more experienced people will chime in here, but I think any all iron, 40-year-old engine will have some bit of rust developing in the coolant after time. There are corrosion inhibitors in the coolant that will slow the rusting process down, but it'll happen eventually. The newer long-life coolants in an aluminum block/head engine are great, but with the older iron block/head engines, keeping on top of the coolant changes can head off problems. Looks totally normal to me. You could flush an old engine to your heart's content and never keep the coolant looking new after even a few miles. Stay on schedule with changes, keep an eye on the temps, and watch for leaks in the water pump.

 

[HawkGunner]

I'm sure more experienced people will chime in here, but I think any all iron, 40-year-old engine will have some bit of rust developing in the coolant after time. There are corrosion inhibitors in the coolant that will slow the rusting process down, but it'll happen eventually. The newer long-life coolants in an aluminum block/head engine are great, but with the older iron block/head engines, keeping on top of the coolant changes can head off problems. Looks totally normal to me. You could flush an old engine to your heart's content and never keep the coolant looking new after even a few miles. Stay on schedule with changes, keep an eye on the temps, and watch for leaks in the water pump.

I'm a stickler for staying on top of my maintenance.... which is sort of a double edged sword.

It's tough to ride around smiling when you know all the little things that need looking after. I pop the radiator cap once a week and check, when it looks funny I get a little concerned haha

 

[Pighead]

That looks kinda normal...

 

[HawkGunner]

That looks kinda normal...

Ok! If you guys say so, I'll stop worrying about it and just change the coolant every couple years like normal.

Thanks!

 

[AlaskanWheeler]

I'd expect it to be a lot more "greener"

 

[Redgrrr]

Just came across this mess, started out replacing radiator haha.

 

[Dizzy]

I've heard that different products will all inhibit corrosion, but they need to stay within the family and not mix, i.e. green with green, orange with orange.

 

[kevos37]

I think a though flush including opening the rear block drain wouldn't hurt. It should be a steady flow of coolant when opened, if not then remove the entire drain and use a probe (wire) to loosen any sediment around the port.

 

[HawkGunner]

I think a though flush including opening the rear block drain wouldn't hurt. It should be a steady flow of coolant when opened, if not then remove the entire drain and use a probe (wire) to loosen any sediment around the port.

That's kinda what I figured. I'm pulling and overhauling the tranny in the fall, so I'll do it then.

For now, it doesn't run hot, or get hotter than what seems appropriate even with a good amount of highway driving in 100°+ outside air temps. So unless the HG blows between now and then, it should be alright.

Unless you think differently?

 

[kevos37]

That sounds like a good plan. Your engine sounds like its running fine, it's just got plaque buildup...lol

 

[GA Architect]

Even an engine that has been hot dipped, reworked, totally rebuilt with all new parts, installed a new radiator, all new radiator hoses and cleaned up parts.....after 30 miles:

Ticked me off, so I drained, flushed, flushed, flushed and re-flushed.......then did it all again.

After a few thousand miles:

Then after a couple of years, the OCD kicked in. Totally drained the green, flushed and opted to run the Toyota Red.

 

[Steamer]

GA Architect's post & pics says a Lot!. Clean steel can start rusting right away. Unless you're the original owner, you'll never know what kind of abuse your cooing system has been through over the years. When you flush, flush and re-flush and the flush water is coming out crystal clear, it often doesn't mean it's clean in there. It just means nothing else is letting go at the time.
Constant clean new looking coolant is achievable. Just a matter of how important it is to ya and how far you want to go with it. How cool it's running plays a part in that decision.
Myself and others have done some radical flushing and posted about it with plenty of pics. Just search here with the word "Flush" with my name as the poster and that'll get ya to a lot of them. Good luck!

 

[goncalotomas84]

Even an engine that has been hot dipped, reworked, totally rebuilt with all new parts, installed a new radiator, all new radiator hoses and cleaned up parts.....after 30 miles:

View attachment 1716596

Ticked me off, so I drained, flushed, flushed, flushed and re-flushed.......then did it all again.

After a few thousand miles:
View attachment 1716597


Then after a couple of years, the OCD kicked in. Totally drained the green, flushed and opted to run the Toyota Red.

Hello just confirm your coolant sthill green or coming again a bit rusty?

 

[GA Architect]

Hello just confirm your coolant sthill green or coming again a bit rusty?

No more rusty coolant, and it would be still be green....but I've since replace the WP and radiator, thus switching to Toyota pink in December 2018.....coolant is still pink today.

 

[goncalotomas84]

No more rusty coolant, and it would be still be green....but I've since replace the WP and radiator, thus switching to Toyota pink in December 2018.....coolant is still pink today.

Thanks, how many times you flush and reflush? What you did just put new green coolant , or used a product to flush radiators?

And now how many kilometers ir years without rusty coolant?

For me the strange and curious is I drove the car from january 2019, with new radiator, restore the car from october 2019 to june 2022, never saw rusty coolant, why only now start to see???

 

[JMZ400]

Quote: "Unless you're the original owner, you'll never know what kind of abuse your cooing system has been through over the years."

That's for sure, I had to use mud puddle water several years ago just to make it out.

 

[charliemeyer007]

Way better than camel urine.

 

[goncalotomas84]

Quote: "Unless you're the original owner, you'll never know what kind of abuse your cooing system has been through over the years."

That's for sure, I had to use mud puddle water several years ago just to make it out.

The car has been sitting for about 10 years. I bought it and it went back on the road in January 2018, with new radiators. I always used green antifreeze until October 2019; I've never seen brown coolant. I restored it between October 2019 and January 2022. I didn't touch the block; the engine was fine until March 2023 when the head gasket blew. I replaced it with a new water pump. Since then, I've used this green antifreeze, which always looks good. I wonder why the coolant has only turned brown now. One possible reason is that after the block was empty for two and a half years without coolant during the restoration, it oxidized.

 

[GA Architect]

Thanks, how many times you flush and reflush? What you did just put new green coolant , or used a product to flush radiators?

And now how many kilometers ir years without rusty coolant?

For me the strange and curious is I drove the car from january 2019, with new radiator, restore the car from october 2019 to june 2022, never saw rusty coolant, why only now start to see???

View attachment 4033787

View attachment 4033788

View attachment 4033789

It was a simple single H2O flush, due to the engine just being rebuilt. I can only surmise that the rusty color of the coolant, at the time, was due to minor rust in the recent hot dipped block, but most was probably from the heating circuit.