71OldsCut

Hi,

I was going to add some transmission fluid and right by the dip stick I saw a tee fitting with a cap on it on one of the coolant lines going to the heater core. I moved it slightly and coolant started spraying out from it. What would this be for? The tubing doesn't seem to be in the best shape so I was just going to go buy a fresh piece and install it, I just wanted to know if this capped tee fitting is required or can I just run a new piece of tubing without it.

THanks!

Koda

That is part of an aftermarket back flush kit. Hose goes there, water goes in, goes through block, and goes out uncapped radiator fill hole.

It's a procedure of dubious provenance, and has been known to cause heater core leaks and excessive mineral deposits from a whole lot of tap water.

You can certainly replace the entire chunk of heater hose without worry. Do the other one at the same time, replace clamps as needed, and have peace of mind.

71OldsCut

Sounds good. I will do that. Thanks

droldsmorland

Often when a standard flush is preformed the heater core doesn't get cleaned out as well as the radiator and engine block, thus it eventually fails. However this flush connection point helps as its close to the core. As you can see the plastic Tee isnt very robust. Flush the heater core (gently) by its self. I suggest you replace both heater core hoses. Before you remove the clamps at the core leave a foot of hose on one side. Then using a low pressure garden hose flush the core. Ill bet a ton of brown comes out of it. Follow the water with either a shop vac or low psi compressed air to remove the tap water. You have to be gentile with the core as its kind of fragile and can be compromised easily if you put too much pressure at it...water or air.
Hook up the new hoses and refill the system. Never use tap water to cut straight coolant. Use the premixed coolant or use distilled water to cut straight coolant. Of course MAW (might as well) do the rest of the cooling system if it hasn't been serviced in a while...including a new high quality 190*F T Stat. Name of the game when flushing is to get a complete flush, evacuate all tap water and chemical flush, refill with fresh coolant.

oldcutlass

The procedure actually worked/works very well and is still available today.

dc2x4drvr

Allan R

How about starting with draining a bit of coolant from the radiator. That's what the petcock is for. Minimize the amount of coolant you'll spill. If you do get some on the ground be sure to flush it with plenty of water as pets are attracted to the sweet smell of antifreeze and can get violently sick.

OP - you can replace this with OEM looking hoses, or ones from O'Reily's or Autozone. In the meantime unless that fitting is leaking it's perfectly fine to leave it alone because it's not hurting anything.

Sugar Bear

Haven't tried this but...make an adapter to attach the garden hose to both of the block drain plugs at the bottom of the block by the motor mounts. Also leave those plugs out for a few minutes when flushing from the top.

Good luck!!?

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