Thanks Jim, the cap was replaced with an OEM cap when the water pump was done 13,000 miles ago, and the overflow tank doesn’t show any evidence of any spillage on or under it.  I’m thinking small leaks too, but I’d like to narrow it down.  The 2.1 has a lot more hoses than my 1.9!

 

Stuart

 

From: Jim Felder [mailto:jim.felder@gmail.com] 
Sent: Monday, September 28, 2015 2:21 PM
To: Stuart MacMillan; vanagon@gerry.vanagon.com
Subject: Re: Missing coolant

 

Old hoses leak microscopic amounts of coolant. Ive had it spray onto the engine in such small quantities that it would evaporate before you could see it. Tighten hoses, replace hoses is about all you can do. But you didn't mention testing the pressure cap. That can send a good deal of coolant into the expansion tank, which can drip on the road through the overflow and you won't know it.

 

Jim

 

On Mon, Sep 28, 2015 at 4:11 PM Stuart MacMillan <stuartmacm@gmail.com> wrote:

Just when everything seems to be sorted out, it isn't.  Son's '87 is losing
over a quart of coolant every 400 miles, and I can't find any leaks.  Rear
heater has been removed, and there is no odor from the front heater.  No
drips anywhere-engine plumbing, heads, transmission cooler, radiator, or
front heater valve.  No evidence of coolant mixing with either the
transmission fluid or engine oil, and that much coolant would certainly foam
oil.

I'm wondering if it's burning coolant, but in my experience failed sealing
rings in Vanagons lead to over pressurization of the system, and that's not
happening. It also runs great. I sometimes notice a faint smell of burning
coolant at the engine compartment vents, but I can't find anything dripping
on the exhaust when the system is pressurized.

Would investing in a UV leak detection kit tell me anything?  It would seem
losing this much coolant would show up somewhere.

Any ideas?

Stuart