Radiator and water pump replacement on a 99 Yukon, 3 questions

[gmdrvr]

Hello tahoeyukonforum people, this is my first post!


1st question; For the next few days I'm going to drive around with chemical flush in the engine. I have to put on the heater to make sure the heating core gets cleaned and I've seen other people do this but they turn the heating blower on high. Is it even necessary to turn on the blower? It's been 105 where I live and I would prefer not to turn on the blower. I would think just putting it on the heater setting would circulate coolant through the core.

2nd question; On the top of the water pump there are 2 hoses I think one goes into the engine block and the other connects to the heater hose. Does anyone know what those 2 hoses are called? I searched online for heater hoses and bypass hoses but all I can find is pre shaped hoses and the hoses I need seem to be straight hoses that are just looped over.

3rd question; How should I flush the cleaner out of the heating core before I put in fresh coolant?


Thanks

 

[TxDrewski]

1) I did a flush and a head gasket Sealer when I flushed mine because I had a head gasket leaking. We ran it for 1 hour, with the blower on. I think days is way overkill.
2) They are heater hoses, you can go down to any parts store, tell them the size you want, and how many ft, and they will cut them to your specs, I would replace them for piece of mind, they are cheap.
3) If your doing it yourself, you need a container to catch the old fluid as you pump new fluid through the system. Undo the lower radiator hose with the container under it (Large Container), and run your water hose to your your fill location, start the truck and cycle the old out with the new. Add your coolant.

I think anyway, thats what I did.

 

[ccapehartusarmyINF.(ret)]

you dont have to turn on the blower at least not all the way turn it to hot and put it on the 1st setting and switch to the windshield vents so you aint got hot air blowin in your face

---------- Post added at 08:57 PM ---------- Previous post was at 08:37 PM ----------

its been 105 were you live? im going to to assume you live in arizona were i live if that is so i would concern yourself to much with the heater core
you can flush you system out with the heater on and you can use distilled water to flush the cleaning chemical out and i stress the "distilled" dont just use tap water or the garden hose distilled water is the pureist ergo the least corrosive

 

[gmdrvr]

Thanks for the tips guys

1) I think days is way overkill.

`On the bottle I bought it said for heavy duty cleaning run it for 3 to 6 hours. I would agree with you that that would be overkill for a normal system but if you seen the inside of my radiator you would agree it needs it. I ran stop leak in there for the last 3 years. When I drained the system so I could add the cleaner it looked like 3 gallons of oil (black dirty oil) I actually had to check the dipstick to make sure the oil didn't leak into the coolant system (it didn't)

im going to to assume you live in arizona

Yep, I think it's been 3 or 4 years since I even turned the heater on.

 

[SunlitComet]

with fan on lowest speed move the the temp knob off the coldest setting detent. that will open the cores valve for flow.

---------- Post added at 11:00 PM ---------- Previous post was at 10:58 PM ----------

just left tucson and marana az a few days ago. best thing i have done all year.

 

[TxDrewski]

I would recommend you go ahead and change that radiator and your thermostat.

 

[ccapehartusarmyINF.(ret)]

yes here in arizona its important that the cooling system is tip top
so a new radiator definatly couldnt hurt and you should replace the thurmostat when you change out the water pump
also make sure your fan clutch is working i just figured out mine wasnt working
after alot of trial and error

 

[SunlitComet]

not really. in az my system is at the 5 year life limit of fluid life. it needs to be flushed out and the system cleaned. if you maintain the proper coolant and distilled water balance and the coolant still has it proper chemical make-up then you should have no issues as long as your cooling fans works. you can still have the nasty in it and still work just fine. also forgot to mention that prestone sells a $7 kit that splices into the heater hose that basically lets you run water in the opposite direction of stock flow to help dislodge and remove sludge. using garden hose water during the process is fine but when all doe with the hose flushing use gravity to feed distilled water thru heater core hose and rad/block areas. this gets rid of certain minerals and deposits in the waters composition that can make coolant nasty quick. use the same to mix your coolant. dexcool is more sensitive to contamination.

 

[gmdrvr]

TxDrewski and ccapehartusarmyINF.(ret)
Yep, everything is being replaced, radiator, water pump, thermostat, coolant reservoir and hoses. I'm just running the cleaner through it to make sure the engine block channels are clean. The cooling system actually works fine but a long crack in the side of the radiator that jb wield doesn't want to fix anymore is forcing me to replace it and I figured since I'm in there I might as well replace everything.

SunlitComet
I seen those kits before and thought about trying that. I also see a guy on youtube use compressed air to push the water out of the heating core into a jug, I might give that a try.

 

[SunlitComet]

just reduce the air pressure a bit to say like 20psi or so.