Waterpumper/Swap Guys - Heater Core up Front

[tristessa]

My buddy's Vanagon and my swapped Bus are both using I-4 VW engines, his an ABA/JH and mine a 1.8T. We plumbed his the same as a diesel Vanagon and swapped the front heat/air box for one from an '86 WBX, putting in a new core and refreshing all the flap seals while we were at it. He should have as much heat from the vents up front as any Vanagon .. but he doesn't.

Mine is plumbed the same as the Passat engine donor, with the exception of there being two cores in parallel instead of one single core. The only other difference between my heater circuit compared to the donor Passat is the distance from the block to the front heater and the heater itself. The fact that it heats much better running down the highway than it does around town, along with the fact that shutting off the valve to the rear core doesn't do anything to improve the heater output up front, leads me to suspect a flow issue.

Even without the CDH, I do get enough heat in the cabin to be comfortable .. eventually. Which is why I haven't pursued it harder than I have, despite having had the last 10 years to play with it.

[TomWesty]

[notchboy]

[TomWesty]

[notchboy]

[tristessa]

Update for anyone who cares --

I just got home from helping my friend on his '81. We installed the rear heater, teed it into the hoses for the front core with a restricter in the line, and added the VR6 after-run electric coolant pump. The pump is mounted at the engine end, wired it to be always-on with the key, and in the hose *from* the water pump *to* the heater circuit.

Even just sitting in the driveway idling the motor, the hoses to the heaters warm up much quicker than before, and get noticeably warmer than they used to. The front heater *core* he has is definitely no good despite his best efforts to source the "good" version. Core never heats up despite inlet and outlet hoses and the end tank being good and warm.

So in conclusion -- if you feel your front heater output is lacking, consider adding a small electric pump. The one we used was from a VR6 Jetta, but there's plenty of suitable pumps in the wrecking yards these days. BMW, Mercedes, Volvo, Range Rover, Prius .. wander around and see what you find.

Gonna have to go get a pump of my own now...

[skills@eurocarsplus]

i'm assuming a vanagon and also assuming he has a shit heater core they've been peddling for vanagons?

I am starting to believe that the smaller cores we run just don't have "it" in terms of a decent design to be that far away from the heat source. however maradyne offers a bigger heater with a in/out bias

http://www.maradynehp.com/pdfs/mm-a1090002_inst.pdf

I think a core designed with that bias would produce more heat on longer runs. when they are 2 feet from the engine, it doesn't matter
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[tristessa]

[Abscate]

I wonder if the guys in Estonia would turn one of these out for you Vanagon guys? They make a pretty decent replacement for the P80 Volvo core for about $35, the only downside is it needs a cycle through the dishwasher to get the machine shop oil off it,
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.ssS!

[vwwestyman]

Appreciate the update!

I think if I were to install a pump in my Bus, it would be wired up so that it was turned on whenever the heat lever was all the way down, utilizing the original contact used to turn on the booster fan.

I may wander around a salvage yard sometime soon.

The fan on my front heater (Vanagon rear heater setup) has an annoying squeak that I haven't been able to quiet, despite several attempts at lubing it. Perhaps when I can no longer stand it, I'll look at figuring how to fit the larger Maradyne heater.

Couple questions: Does anyone know the estimated BTU output of the Vanagon rear heater? I've looked a few times and cannot find a number.

If I were to buy the large Maradyne heater and modify the face plate to only have one outlet (to tie into the Bus heater tree) how much of a difference would that make to it's ability to provide heat? What I mean is, if it significantly reduces it's ability to provide heat, then perhaps it wouldn't be worth trying to figure out how to engineer fitting it.

As I'm sitting here typing this-the front heater is currently mounted to the front splash pan. I wonder about moving it to under the floor in front of the radiator, and ducting the heated air all the way to the front. Would be more room for fitting, but you'd also probably have an issue with the air cooling on the way to the heater tree.
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Dave Cook

President, Wild Westerner Club

1978 Champagne Edition Westy, repowered to '97 Jetta TDI
1973 Wild Westerner
My Thing

[tristessa]

[vwwestyman]

Hmmm...

Looks very similar to the Heater Craft heater I originally used, actually.

I believe it was sold under a different name. I swapped to the Vanagon core because it seemed to put out more heat. I attributed the difference to finer/more fins.

Then I installed the heater in my boat, because why not?

So maybe all that means my best bang for the buck for an improvement would be the circulation pump.
_________________
Dave Cook

President, Wild Westerner Club

1978 Champagne Edition Westy, repowered to '97 Jetta TDI
1973 Wild Westerner
My Thing

[tristessa]

I've seen them sold under the Maradyne and HeaterCraft brands, also non-brands sold by Jegs and Summit Racing. Interestingly, it looks like they're mostly made with a plastic housing these days not metal like they were when I bought mine. Apparently nylon, which is a bummer for modifications because ABS is so easy to work with as far as gluing & filling...