radiator?

[Ed Fenwick]

Aloha guys, 'wife and I drove up the mountain the other day. When we got home I saw a puddle of coolant under the truck. 'looked in the cap and it was very rusty looking. I put in a flush and new coolant with some K5 stop leak. It looks to be coming from the plastic drain valve. Are those things replaceable or do I have to replace the radiator? Also, how tight should those things be? Youtube says finger tight!!! I put in snug.
God bless Ed

 

[DILLARD000]

Aloha guys, 'wife and I drove up the mountain the other day. When we got home I saw a puddle of coolant under the truck. 'looked in the cap and it was very rusty looking. I put in a flush and new coolant with some K5 stop leak. It looks to be coming from the plastic drain valve. Are those things replaceable or do I have to replace the radiator? Also, how tight should those things be? Youtube says finger tight!!! I put in snug.
God bless Ed

Assuming Coolant+Radiator+Cap+Hoses+Pump+HeaterValve+TStat+Housing+... never serviced\replaced?
Plastic Tanks+Drain on your 2002 ExST factory original Radiator are known failure items;
at 18+ years old they've done their service, likely cracked\leaking, ready to be replaced.
Strongly recommend a full service of your coolant system, replacing above components;
Also PCV CoolantWarmingLoop is not needed in HI & a source of leaks, can be deleted.
Also PCV Valve & 5/8" rubber vacuum hose elbows, known leakers, should be replaced while your there.
Hope this helps.

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[EddieS'04]

Ed,
Not sure about your drain valve. On my '04. It came all the way out on me one time, and there was an o-ring on it.
Maybe that could be the leak.
Lord Bless

 

[antny024]

You can try and replace the petcock valve in the radiator....BUUUUTTTT... If there is rust, that means there was not the proper amount of coolant in the cooling system. That is what allows the system to oxidize and rust. You put in a flush and radiator sealant. That's not good. Sealant is only a temporary fix and needs to be completely removed from the cooling system. Usually when the cooling system on an older vehicle is flushed, it stirs up sediment that hasn't moved in MANY moons. When those particles start to float around the cooling system other things begin to leak.. I just replaced the water pump, thermostat housing and upper and lower hoses. The radiator was clean and looked fine. When I drove for about 3 days, I saw the radiator had begun to leak from the seam in the side tank. I knew I should have replaced it with the other parts, but I'm lazy. If you replace only the radiator I'd keep a really close check on it after. Make sure nothing else begins to leak. Good luck!!

 

[DILLARD000]

Yep, I'd first do a full coolant system flush. Fill it with distilled water. Drive that for thirty minutes. Redrain the system. Then replace the radiator & all other coolant system parts older than 5yrs. Finally refill with 50/50 & fully burp the system. This way you don't contaminate any new parts with old coolant, rust, sediment.

 

[Ed Fenwick]

Yep, I'd first do a full coolant system flush. Fill it with distilled water. Drive that for thirty minutes. Redrain the system. Then replace the radiator & all other coolant system parts older than 5yrs. Finally refill with 50/50 & fully burp the system. This way you don't contaminate any new parts with old coolant, rust, sediment.

Thanks guys, I did the flush then DI water for a day then 50/50 antifreeze. The radiator is a little low but the level is holding. I haven't taken any long rides yet, (8 miles to town is all), I don't see anything od the carport floor.

 

[Todd Z]

The o rings go bad, and some of the aftermarkets are crap. you can replace the petcock.... the o ring could be bad too.

 

[Tylerxp2]

Ed,
Not sure about your drain valve. On my '04. It came all the way out on me one time, and there was an o-ring on it.
Maybe that could be the leak.
Lord Bless

Same on my 04, that's how I drained mine and Its didn't leak.
Now Im chasing another small leak. I think my ST needs a lot of New Hoses... Ugh!