Wrenchinjoe

I recently replaced my radiator because the original part was developing numerous pin hole leaks along the top. I went with a Ready-Rad from AdvanceAuto with a lifetime warranty for approx. $130.

However, the new radiator leaked on me after only 5 days The leak appeared to come from the joint where the aluminum core joins plastic bottom. Advance swapped it out no problem and the 2nd new radiator works just fine.

My question is this: when I drained the coolant the first time, it drained 2+ gallons of old coolant (that looked pretty clean really). When I drained the coolant the 2nd time while replacing the deffective radiator, only 3/4 of a gallon drained out???

Both times I did the job the truck was stone cold.

My only guess is that the thermostat did a better job sealing the 2nd time having been flushed with new clean coolant from the 1st replacement.

Any ideas?

mightymouse

iTrader: (6)

If it runs perfect i would leave it for a while. If it doesn't i would give the system a flush and replace the t-stat. When you drained the coolant the second time was it dirty at all? Did you replace the t-stat when you replaced the radiator?

myyota

You should have gone with an all metal radiator, its just a matter of time before those plastic tank radiators start to leak. I bought a new 3 core radiator for my 86 4Runner about a rear ago for around 150.00 dollars. I can`t tell you why you only got 3/4 of a gallon out when you drained it, but how much did it take to refill it ?, if it took more than that 3/4 of a gallon to refill it after replacing the radiator then your head gaskets might be going bad.

mt_goat

Did you replace the t-stat?

betelnut

I'm trying to figure this out too.

The lower radiator hose connects to the t-stat housing, so the t-stat on a cold engine would keep the water from flowing out of the engine to the radiator where the drain is.

The engine's gotta be pretty warm for the t-stat to be open, so seems like you usually wouldn't be able to drain the whole system through the radiator petcock.

How come sometimes you get more coolant, sometimes less?

Since my last job, I've learned there's a drain cock on the engine too, reportedly in front of the oil cooler, driver's side of engine. Maybe even one more on pass. side near the A/C bracket.

https://www.yotatech.com/forums/f116...t-size-163909/

Wrenchinjoe

Mightymouse, yeah it runs perfect, no temp spikes upon first start either time. Coolant that drained was quite clean upon first drain and brand new at second drain.

Dale, I did not replace the t-stat at this time. I will be doing a timing belt this spring and will replace the water pump, t-stat, and hoses at that time. This was a quicky job and essentially a flush and fill.

Myyota, I know I went cheap, but the lifetime warranty gives me a little piece of mind. Also, no coolant loss from heads... the exact quantity that drained out initially is what went back in to top her off.

I am thinking that the t-stat was partially open during the first drain, so it drained the whole system. Any t-stat sticking is a worry, so that may be this weekend's project.

mt_goat

Ok, I thought if you had replaced the t-stat (with a jiggle valve) with a t-stat that didn't have a jiggle valve that would account for the coolant in the block not draining out.

BTW if you put the jiggle valve at 12:00 it will get more air out when bleeding, if you put it at 6:00 it will let more coolant drain out when draining. Personally I think 12:00 is better.

mt_goat

I actually prefer the plastic tank over the solid copper/brass radiators. Now before anyone says I'm crazy let me explain why. A plastic tank rad always has an aluminum core and its really the aluminum core I like (not the plastic tank part) Even better is a solid aluminum radiator but those are expensive for a good one.

You're lucky you got a lifetime warranty on it. They sometimes leak right off the bat, like you found out, but once you get a good one they will go for many years. I had the same thing happen with my BMW, new rad leaked...replaced under warranty and the replacement has been fine for years now.

Reason I like alumiunim cores better is they are made with one (sometimes 2) large core rather than 3 small cores. The one large core has more core to cooling-fin contact surface than 3 small cores do. Also the one large core is harder to clog up. Plus the copper/brass weight much more.

Wrenchinjoe

Thanks for the feedback Dale