Where's the coolant leak?

[phil]

I have a slow leak in my coolant system but I can't find where it is coming from.  This picture is taken near the driver's side rear wheel. The drain is for the water storage tank. If you look at the picture below you can see the cross memeber of the frame is wet with coolant. Somewhere, somehow coolant is leaking into the frame of the van, running down the crossmember and dripping on to the ground.


This picture is the other side (passenger side). You can see it is damp with antifreeze too. Where the devil is it leaking? Has anyone seen this before??  Phil

[phil]

I think I found it !!!
 IT is in the heat exchanger under the rear seat... At least I think so.  I see some coolant there. Somehow it is dripping down into the frame crosss member.
What does that white knob on top do? WHat does that lever do? Anyone know?

[Stanagon]

Phil,

The metal lever shuts off the flow off coolant to the rear heater box assembly (on-off). Perhaps the leak is at this valve or a nearby connection.

The white knob had me stumped. I checked with a co-worker who has owned a number of Vanagons and he thought it was simply a retainer for a trim panel cover for the heater valve. Having the  cover in place would prevent the heater lever from accidentally getting shut off or damage to the coolant lines caused by storage of camping gear under the rear seat, etc.

Hope this makes sense.

-Stan

[Red Baron]

I had the same problem with coolant leaking from the rear heater on our '87 Westy. Coolant puddled all over the floor under the rear seat and eventually leaked out on to the garage floor where I first noticed it and then started checking for the leak. First thing was to mop up the coolant on the deck around the heater and then shut off the valve that lets hot coolant into the heater. No more leaks ever since!. In all the years we've had this Westy, we only used the rear heater once. The leakage can only come from two or three sources: The "O" ring in the valve on/off body, a faulty hose connection  ( coolant in or out ) or a major leak in the heater core.

My recommendation is: Check the inlet/outlet hose connections for leakage, then just shut the valve off and clean up the mess on the deck. It worked for me and if you really need that so-called "extra heat" from under the rear seat, you're in for a real PIA job to pull the heater and go thru all that routine of draining the coolant, checking the heater, fixing or replacing it and then replacing the coolant.

I think most all Westfalia Waterboxer Campers were equipped with a box like cover over the rear heater assembly to prevent damage to the heater from gear or tools stored under the seat. There is a slot cutout on the left side of the cover as you face the rear seat where with your finger or something else you can move the valve lever on/off. If I'm not mistaken, there is something in the Bentley Manual about the rear underseat heater.

[Red Baron]

I hate to say it but it looks like you've got severe corrosion problems under there in addition to the coolant leak.

[phil]

Well, that will be my plan of action. I'll mop up the coolant and clean the area. Then I'll run the van for a while and see if it is leaking and from where. My guess is the heat exchanger and not the valve or the hose connection.
I am going to have to guess which position is "OFF" with the valve. My guess is all the way clockwise.

Corrosion. Yes, it looks pretty nasty under there but is actually better than it looks. I'll clean it up a bit and put a coat of paint on it.

[Tikibus]

Now I see what yer up to...

Crafty dog.. Woof!

The Dude Abides.

[Red Baron]

Below is a copy of Page 46 from my 1987 Vanagon/Transporter Owner's Manual which explains the workings of the secondary heat exchanger.

[phil]

Well, I'll go mop everything up, reload some antifreeze, pull the lever rearward (off) and see if I get anymore leaking.

[phil]

It looks like the white drain cap was broken or got broke somehow.
Half of the drain is still screwed into the drain. But, as you see it is leaking from here. The engine was on when this picture was taken, hence the fountain of coolant. Now what to do Hmmm. The on/off lever doesn't work, valve seals probably shot.

[phil]

Bypass is the answer... for now. I managed to get the broken plastic drain thingy out. I even glued it together, see picture (won't hold under stress).
I went to my local auto parts store and bought these adapters (see picture). I now have the coolant bypass the whole heat exchanger. It should work.



Yep, that was it. No more coolant leaks. Problem solved.

[rmace]

Easy kiwk fix BUT the top hose is kinked, no water flow. Not good the auto store sells 90s instead of straight. You do not want to resrict water flow. just my thoughts the Con Kid

[Vanagonjr]

The white tab on the heater is a bleeder valve.

You don't want to bypass the system that way.  Block each hose separately.  This loop also feeds the front heater, and it's feed is from the line to the radiator (ditto for return) the coolant will take the route of least resistance.  This means that you will actually reduce some of the flow through the front radiator and also through the front heater, should you want heat.

I removed my rear heater, plugged each hose with a shoulder bolt (cutting off the threaded part).  You can pour some coolant or water into each hose end then plunge the bolt in, spilling a bit, and then clamp.

I like the extra room under the rear seat.  Since I don't use the van in cold weather, I'm not missing the rear heater.  I might install a new one some day, but I am doubting it.

I might even replace the plastic Tee's that feed the rear heater when I install new heater hose to the front heater.  That way, I won;t even have the hose ends back there.  I might even find some electrical item to use the fan wiring to drive!

On my Westfalia weekender, it seems that the plastic bulkhead that is below the seat, tilts back at the bottom (from the front of the van towards the heater), my Westy wood grain one was straight-up.  I think if I made a new bulkhead, I could even gain more under seat space - with a family of 4 that would be nice.  

Right now I just need to fix my own coolant leak and get running again!

John

[phil]

Thanks for everyones help.  Well, the point was to stop the leaking.  I was only getting around 40 or 50 miles and then I would have to add coolant. That was a regular PITA. And, it has been going on for months. It is hard to spot leaks in wet winter weather. It is so nice not to worry about it now.
The kink in the hose bothers me but my auto parts store here in Yorkville didn't have a 90° elbow. I spent a long time looking too.

In the end, I don't think it really matters much how to "plug" the system.  Ideally, in a closed system, which is what a coolant system supposedly is, the water pump only function is to overcome the friction of the coolant in the pipes. Afterall, the weight of the coolant going up equals the weight of the coolant pushing down. I remember that from school.

[MrLiMBO]

Just buy a new white plug and oring from VW.  It's not that big a deal.  Except that gallons of coolant are leaking out that hole until its fixed... I've seen them blow off on a number of occasions.  I believe its some sort of bleeder valve.  But I'm not certain.  I've seen guys jam bolts in the that hole and hope it stops leaking.  I would take out that whole unit, clean out where it was and take apart the heater and clean it too.  That core has a tendency  to leak too.  You might notice the rear windows fogging up when its running.  If you don't use it that much, then just by-pass it, remove the unit and you'll have more room for junk. =)