Bleeding inverter coolant nhw11

I used no tubing on the bleeder nipples, just a rag to catch the fluid that sputters out when doing the bleeding. I bled it by squeezing the hoses coming and going to the pump. One more than the other but can not remember which one and it bled fairly easily. First time drained my 12V battery, second time less time no troubles.
TomK

 

I've become better at this over the years as I do it more.

One thing about Gen 1 is that there are two bleed valves. One (the nearer to the side of the car) is on the pressure side of the pump, that's the one you can just crack open and watch fluid come out of for as long as the pump is running (and there's fluid in the loop). On that one I do run a tube back to the reservoir, so I'm not just pumping fluid out on the ground. You can leave the pump running for a while and watch the flow through that tube, you'll keep seeing occasional bubbles for a while, especially when you bounce the car or shake the other hoses.

The other bleed valve, the one nearer the center of the car, is on the suction side of the pump. If you open that one (with no tube on) while the pump is running, you'll just let air in, not fluid out.

Early on, I measured the suction at that bleed valve, at around -10 inches of water. What luck, the valve is more than 10 inches above ground, so you can set a mostly-empty coolant jug on the ground and run a tube into it from that bleeder, and as long as you start with the tube full of coolant, the drop is greater than the suction at the valve, so it will steadily siphon fluid out while you leave the valve open, even with the pump running. That way, you have a steady outward stream at both valves, and you can just watch both tubes to see the bubbles leaving the system as you keep bouncing the car and shaking/squeezing hoses.

You do need to watch the reservoir and top it from another coolant jug, since you have this constant siphon action into the jug on the ground. You never want the reservoir getting so low that air gets slurped back in there (go back to start, do not collect $200).

Also, about 5 years ago I took both bleeders completely out, and put them back in after coating the threads with never-hardening sealant (I used Hylomar blue stuff 'cause I had it around, any glycol-resistant never-hardening thread sealant should be ok). Without that, the pressure-side valve loses a mess of coolant out around the threads, besides what goes through the hose back to your reservoir, and the suction-side one pulls air in around the threads. The Hylomar put an end to both problems.

-Chap

 

Looks like the web site for the Hylomar blue stuff has moved.