The reservoir tanks get pretty scuzzy after a few years. All our 940 reservoirs have the low anti-freeze sensors in them so I don't want to replace them.

Has anyone found a good way to clean them out? I have tried detergent, bleach, ammonia (not with the bleach), and a few other things. There is no way to reach inside the many partitions with a brush.

Thanks
--
Mine:4-940s running, 1-740, 2-940 parts, dtrs:3-940s running

Just went thru this with mine after the leaky head gasket let oil into the coolant. After many attempts with various products and methods that did not work (detergent, simple green, totally awesome (caustic) cleaner, purple power, aquarium gravel, etc.) The one method that did work immediately was a handful of oilsorb (like simple clay-based kitty litter) and some gunk engine degreaser. Shake it up and rinse it all out with water. Came out clean clean clean!

The only downside was the odor of the engine degreaser (petroleum based) lingered in my clothes.

Perhaps a mixture of coarse sand or fine gravel, fill it about 3/4 full and shake it as though your hair is on fire. Followed by a GOOD rinse.

If you can remove the tank and sensor, plug all the holes and put some vinegar, clr, or other cleaning fluid in there with some gravel and shake it.

Marty

I threw my old one out. It can't be cleaned. I can't even see the coolant level unless I open the cap.

Got me a new one then I'd clean the reservoir once every 6 to 7 months, more so when I see some accumulated rust at its bottom. Just drain a bit of coolant via the radiator petcock so that the water level falls just below the reservoir, took the reservoir out and clean with dishwasher soap. When finished just add back the drained coolant. Maintained this way the plastic stays reasonably clear with no rust stains.

Regards,
Amarin.

Try some CLR.

You might find it at the supermarket or at a hardware store with the cleaning supplies.
--
Eric
Hi Performance Automotive Service (formerly OVO or Old Volvos Only)
Torrance, CA 90502

get a brush at a plumbing store for use on a Weil Mclain boiler!!itbends& can get all corners

The one for my 240 was cheap -- just buy a new one. That plastic ages/fogs with heat/time and can be stained with chemicals. You won't get it clean.