Coolant Disappearing

My VX has 55000 miles on it. I decided that it would be a good idea to replace the heater hoses and upper and lower radiator hoses. Even though they looked ok I didn't want to take a chance getting caught off-road somewhere.

Everything was fine before I started this project!

I bought a set of Gates hoses. The heater hoses were really hard to replace. The connections to the heater are between the engine and the firewall. It is really a tight squeeze. I really struggled with that. Now that I have my new hoses on, small amounts of coolant disappear when I drive. I mark the overflow reservoir with a pencil line before I start up and then after the engine goes cold again I check the level. Every time I drive for about 1/2 hour or so, the reservoir fluid will drop about 1/8 inch. I've looked at all my connections with the engine running and don't see anything at all leaking. It is very frustrating because I almost never had to add coolant before this. I feel like I should have just left it alone. Could the heater core been damaged somehow when I pushed the new hoses on? Anyone have any ideas?

Slide a piece of paper up behind the heater core under the dash. Go for a drive. Pull the paper out and check for wet spots.

It is also possible you didn’t get the clamps between the firewall and engine completely tight. Recheck all of your hose connections.

Thanks so much for the tip! That's a great idea. I'll try a piece of paper and tightening the clamps. I've been reading about your build. I wish I could be as good at mechanics as you are!

Thanks for the vote of confidence! But really I just read a lot and take my time. If I was paid by the hour I would be fired! LOL!

OK. I drove the VX until it was fully hot. Then I shut it down, thinking that it would build the most pressure right after it first stops. I took my high powered flashlight and dental-type inspection mirror and looked at everything I can think of. I can't find anything leaking anywhere. I slid a sheet of paper under the heater core. No leaks on the paper. Not sure where the coolant has been going. Someone suggested that there may be air-bubbles in the system that need to work their way out. Perhaps I should take it off-road and bounce it around for awhile. I snugged up the connections and refilled the reservoir. Hopefully it will stabilize...

The VX does have an issue with air bubbles getting trapped. Just to be safe, check for water bubbles in the oil. If there is, it’s most likely a head gasket. But air bubbles are a good possibility.

Just an update. The coolant kept disappearing for about 175 miles then it stabilized. It must have been air bubbles. Sure took a long time to work out of the system... :grino:

Yay!!!

That's what I said! Yay! One less thing to worry about. Now I can worry about something different on the VX. Of course, my problems are minor compared to yours. I really like reading about your progress with the build. Just think, you will be an expert in all areas of the VX by the time you are finished! :happyface

Hahaha! If I only was not forced to be.