question about opening the coolant hoses

80Zcorn

Veteran Member
Oct 10, 2016
906
Israel
Hi
I'm not a mechanic so I'm asking before I'm doing what I want to do just to be on the safe side...

I want to replace the clamps on my radiator hoses since the current ones are ugly and old and to reroute my temp sending unit (which means unscrew it route it and screw it back again).
If I'll take the hoses off, I know that most of the coolant will probably end down on my garage floor, and that's ok... But after I'm connected to the hoses or the temp sending unit, can I just refill the radiator and that is all or should the system be cycled a couple of times, or should I bleed it? how does it work?
 

mallard

Veteran Member
Oct 3, 2013
2,230
SK, Canada
What I do is make sure the rad isn't too low and simply run the engine with the rad cap off until the thermostat opens and you can see how much you have to "top off" after the circulation starts fairly vigorously. Put the cap on then shut the engine off. As long as there's some coolant in the overflow tank, the overflow should start it's job. Once the engine has cooled down enough, you might want to just "back off" the cap a little and see if there's a bit of a "swooze" of fluid into the overflow just to be sure.

There are no doubt more "scientific" methods but the above is what I've done with success. Of course we're talking about cars that are 35 + years old too.
 

COPO

Veteran Member
Lifetime Gold Member
Sep 15, 1999
22,701
Ontario, Canada
Drain most of the coolant from the rad drain pet cock into a bucket and reuse it. If you ever work on the heater core hoses DO NOT yank on the hoses or try to twist them off or you will break the solder joints. Hopefully the hoses are long enough to make a slit at the end then cut the end even and reuse the hose.
 

sandlapper

Veteran Member
Oct 9, 2020
1,875
SE CSA
All good --- but begin by raising the car's front end --- that'll help to burp any air out that's left after your refill steps. I like to refill directly & slowly into intake manifold's hole for t'stat housing. I start it while front end's raised.

Where there's adequate room to do so, Some folk double-clamp at water pump, t'stat housing, both rad connections.
 

80Zcorn

Veteran Member
Oct 10, 2016
906
Israel
Thanks for the answers guys!

BTW - I don't have an overflow tank.

I never worked with heater hoses so thanks for the heads up COPO! Can you find a pic of the joints you are talking about since I have no idea what are they...
But to make it simple - I gues I will go with wnmech suggestion... How are they holding up for you by now?
 

sandlapper

Veteran Member
Oct 9, 2020
1,875
SE CSA
does your radiator neck have a small tube connected 90* to neck ??? Like in the drawing below?

If yes --- you should fit an overflow aka recovery tank with correct cap.

1670385032091.png
 
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