Author Topic: VW cooling theory.... (Read 3294 times)

westcoaster · « **on:** October 14, 2007, 10:31:05 pm »

Please bear with my stunted brain cells here....

Water comes out of the head on it's way to the radiator un restricted. It is cooled in the radiator and is on it's way to the water pump where the first thing it hits is a thermostat with it's temperature sensor on the water pump or suction side.

Then there is the other output from the head that goes to the heater core. After the heater core it is on it's way back to the water pump. I would guess there is no thermostat on this circuit.

Then there is a radiator bypass hose. This comes off the head with a "T" one side goes to the rad and the other goes straight to the water pump. once again assuming no thermostat.

Simply by typing this out I think I have the theory of the system understood. It would just seam by drawing cold water from the rad over the thermostat that the thermostat would never really open. If the water from the bypass hose is hot enough it would mix it up enough to open the thermostat....

does this sound right?

Does the stock VW heater core have a valve that shuts off the coolant flow to the heater core?

The samurai that my motor is swapped into does have a valve to shut the flow of coolant off to the heater core. This means that one circuit is not circulating anything. Is this bad?

Thanks,

westcoaster · « **Reply #1 on:** October 14, 2007, 11:19:46 pm »

Thank you for clearing that up.

A separate but somewhat related question. Are there any other "thermostat housing" configurations?
The hose from the radiator enters the water pump (and the thermostat) parallel to the crank shaft. Is there such a housing that enters at a 90* angle to the crank (or any other position for that matter...)
With the way it fits in the samurai, my lower rad hose rubs on the engine mount. I would like to try and solve this before it turns into a problem in some remote location....

Thanks,

Black Smokin' Diesel · « **Reply #2 on:** October 14, 2007, 11:51:06 pm »

I don't think there's any other thermostat housing configs with this type of waterpump. The only difference is that early MK2s and most cars before it had an aluminum housing. VW switched to cheap plastic flanges somewhere in the late 80's. If you get your hands on an aluminum one you could have it cut and welded the way you want.

Maybe you can fit a coolant flange there (the ones on the head).

westcoaster · « **Reply #3 on:** October 15, 2007, 12:06:09 am »

Well, that somewhat helps me somewhat date my motor then :lol:

I have the cheap plastic one....

I'm not sure what the coolant flange looks like when it's off, but the thermostat housing is quite wide (almost the size of a pop can top) and looks like it is made in such a way to hold the thermostat securely in place.

055 121 121 F

Oh my! That part number turned up all kinds of stuff.... Off to do some reading.

Thanks,

Baxter · « **Reply #4 on:** October 15, 2007, 02:51:22 pm »

The Vanagon water flange thermostat cover thingy is about 45 degrees to the engine.

BellCityDubber · « **Reply #5 on:** October 15, 2007, 03:03:31 pm »

Quote from: "Mr Brick-Yard"

The Vanagon water flange thermostat cover thingy is about 45 degrees to the engine.

IIRC so is the fox waterpump thermostat flange.

Baxter · « **Reply #6 on:** October 15, 2007, 03:50:47 pm »

aarrgh, cross ocean vw model mix up conundrum!
WTF is a fox? here it's a base model Polo, but the Polo didn't get 1500cc+ engines..

Black Smokin' Diesel · « **Reply #7 on:** October 15, 2007, 04:22:42 pm »

Quote from: "Mr Brick-Yard"

aarrgh, cross ocean vw model mix up conundrum!
WTF is a fox? here it's a base model Polo, but the Polo didn't get 1500cc+ engines..

A Fox is kinda like a bastard VW child... The engine is longitudinally mounted even though it's front wheel drive, the front suspension is somewhat peculiar, as is the steering gear. I don't think it's related to the polo in any way. The Fox is based on the Bx chassis (not to be confused with the passat chassis, B1, B2, B3...).

Baxter · « **Reply #8 on:** October 15, 2007, 06:49:54 pm »

Sounds like a Passat, but didn't you lot call them Quantum?
Ah, feck it, Google...

aaahhhh, it's a Santana.

A santana here was a passat saloon.

VW Smokr · « **Reply #9 on:** October 16, 2007, 02:32:02 am »

Not exactly a Santana either. More like an updated, but de-contented(and made in Brazil!) Passat 1 (AKA "Dasher" in North America). VW Fox, as sold in U.S./Canada was definitely smaller than Passat 2(AKA "Quantum" in North America).

And that's not to be confused with the VW "Quantum" now being produced/sold in mainland China!

J.R.

Author Topic: VW cooling theory.... (Read 3294 times)

Baxter

Baxter

Baxter