Coolant recovery bottle question

[DutchBoy]

On my ISC 8.3, the coolant recovery bottle is always empty. I fill it before a trip, & upon return it's empty again. No leaks, radiator cap holding steady 15 lbs on the expansion tank, engine running fine (thinking head gasket here). I did have a complete flush done approx. 5000 miles ago. Any comments would be appreciated.

DutchBoy

[JManatee]

did you bleed all the air out of the system?

[AFChap]

It would seem that all the air was not bled from the coolant system.

[J Walker]

It can take a long time to get all the air out. My overflow tank level goes down slowly for about 5,000 miles after a coolant change. I thought I had a leak but it the level stops going down. An oil analysis will clear up the possibility of coolant in the oil. An inspection under the MH for signs of leakage should be enough to determine if you have a leak.

[DutchBoy]

Thx for the responses. Looks like it's more than likely air in the system. We'll give it a few more miles before I get too worked up about it. I do believe I'll have an oil analysis done, just for my own peace of mind.

[justimagination]

DUTCH BOY...........check the small tube going into the overflow bottle and make sure you have a good seal where it attaches to the top, mine required a small hose clamp to correct. Slowly take the radiator cap off when the engine is fairly cool, start the engine , turn you heater on, and let it run until the top of the radiator is warm and the heater air is also HOT, this will get any air out of the system. Once your at this point, fill your overflow bottle to the UPPER level mark, add to radiator just below the neck where the cap goes and install the cap, your done. After your next trip, check the level when COLD, it should be on the LOWER mark on the overflow tank. iF THIS FAILS, YOU HAVE A LEAK. good luck, happy trails & travel safe.
David G.

[deandec]

My manual and the coolant surge tank label have instructions for bleeding the air from the coolant system. The shop mechanics do not always follow the instructions as I learned from experience.

It takes about 15 minutes to execute and should stop your coolant loss.

[J Walker]

Dutch Boy, Thanks for the tip. I will try it next time I change coolant.