djMaru

So my friend just told me he has issues with his 93 sc300 overheating on it.

So he said, he changed out the water pump, all hoses looks fine. and there is no white smokes, radiator was new from previous onwership. but his fan shroud is cracked, I don't know how bad the crack is.

So I was thinking maybe t-stat might be suck or water pump. He said, it leaks from the bottom of the engine when it's turn on. If there is green fluid on the ground does that mean this is an issue of the water pump that he has to replace?

if anyone could chime in?

thanks

eknine9

iTrader: (8)

T-stat is located on the left-lower radiator hose right where it goes into the block, if it's leaking from there his t-stat may be stuck.

Also tell him to switch rad fluid. Green fluid will rot the rad hoses, he needs to gt toyota red and dilute it 1:1 with water.

t2d2

iTrader: (8)

Could you expand on that? I haven't done a radiator flush yet, so I haven't really researched the topic, but I've read several times that the "proper" coolant is the red Toyota stuff. However, I've also read in numerous places that the different colors are all the same. Also, for non-red to rot the radiator hoses (first I've heard of that), it would beg the question of what type of hoses is Toyota using that no one else does, and why? A hose that can't take normal coolant doesn't sound like a great idea, when a normal hose works just fine for every other application.

eknine9

iTrader: (8)

I don't remember the exact thread, but when I was replacing my T-stat I did a drain and fill as well and switched to Toyota red, I believe the specific reason had something to do with it being ethylene glycol and having properties that were anti-rust which some other rad fluids don't have and can cause early failure with the stock radiator. Also I believe toyota red clumps up like boogers around leaks which is nice. I'll try and do a search to see if I can find any of the threads that influenced my choice when I did my drain and fill. But the benefits of running toyota red far outweighed the cost when I was looking it up.

Sorry for saying rot earlier, I wasn't paying much attention when I typed it out. It was definitely rust that was the issue.

t2d2

iTrader: (8)

Okay, that makes more sense. However, even if there is a difference, how many of us still have stock radiators? It's sort of a moot point for many, isn't it?

eknine9

iTrader: (8)

https://www.clublexus.com/forums/per...ne-glycol.html

This is the only thread I found specifically on the issue, it's mentioned here and there all across the forum though.
Looks like the toyota red is less acidic and has less silicates, but its not an actual issue on our iron block 2JZ's, jury is still out on the aluminum 1UZFE though as it may be that toyota red is the most beneficial for the 1uzfe. However, that being said I'd still stick with Toyota red coolant diluted with distilled water in my 2j than green coolant, which I found is also ethylene glycol based. But it may not be as dire of an issue as I made it out to be.

To be clear.
No color coolant will rot the radiator lines.
Orange dexcool will eat away at the gaskets and metal and should be avoided in all vehicles.
Ethylene glycol green and toyota red are fine in the 2jz.
Ethylene Glycol green may not be the best in the 1uzfe, but I'm still not sure.
Toyota red is less acidic and doesn't contain silicates.
Toyota red will gunk up around leaks and can slow the leak.
Toyota red and green should not be mixed because they'll turn into something resembling jello.
Toyota red is also a bit more expensive than Ethylene Glycol green.

Sorry for causing confusion with my first post, I was trying to speak on something I only half remembered from over a year ago.

t2d2

iTrader: (8)

We've all been guilty of a faulty memory at some point or another. Well, I can't remember ever being a victim of such myself...

The thread you found is exactly what I've read on various car forums and DIY guides: green coolant is perfectly fine for aluminum blocks. So, if iron vs aluminum is the only reason to use Toyota red, you're probably wasting your money. Maybe there's more to it, but that thread certainly isn't very compelling for making the point. But hey, that's why I asked for clarification. All I've seen is assertions to use Toyota red, but never a good reason why.

eknine9

iTrader: (8)

No offense, but your mechanic sounds developmentally challenged. They don't even cost that much from the dealer. And a mishimoto aluminum radiator can be found for less than $200, so hopefully he just made a mistake or had a slip of the tongue.

djMaru

well my friend said, that he is going to change out t-stat and head gasket