Heater hose connections

[vtullomk4]

Finishing install of FF Vintage Air heater in my MK4.

Looking at many forum posts, I see different hose connections. This is what I have now:

Right (driver) side of heater - hose to manual cable control valve and then to fitting in manifold
Left (passenger) side of heater - hose to water pump nipple.

Have seen several that are swapped. Just looking for confirmation

Thanks.

Vince142597142598

[Norm B]

It doesn’t matter what connection the valve goes to on the heater core as long as the hose it is in goes to the intake manifold and not the water pump.

Norm

[vtullomk4]

Thanks. And can I put the water gauge sending unit right next to the heater hose? Appears to be in the neck not the manifold. Sniper sending unit is on the other side. BP347.

[Norm B]

I routed mine different than you did. Here’s a picture. The temperature sender for the gauge is circled and labelled 1. The heater valve is marked 2. I had to put a bypass system in to get the gauge to read correctly. The gauge would read much colder than the Sniper temperature indication unless the heater was on. A bypass heater valve would have accomplished the same thing.

HTH

Norm

[egchewy79]

You should be fine putting your water temp sender in that threaded bung just behind your radiator hose on the water neck. You have a bypass hose going to your water pump that allows circulation of coolant even when you're thermostat is closed

[Norm B]

You should be fine putting your water temp sender in that threaded bung just behind your radiator hose on the water neck. You have a bypass hose going to your water pump that allows circulation of coolant even when you're thermostat is closed

I wouldn’t do this because because you won’t get a temperature reading until the thermostat opens. If the thermostat fails the engine will overheat without the gauge reading an increase in temp.

Norm

[vtullomk4]

Great. Thank you all!

[egchewy79]

You should double check, but I think the bung is on the rearward side of the thermostat. At least mine was. If not, I agree with Norm. I also drilled a small 1/8" hole in the top of my thermostat to have a small coolant flow even with thermostat closed in addition to the bypass flow.

[vtullomk4]

I guess I am now confused. Just re-read the BPE manual and states the following:

“The open barb on your water pump will run to your heater core. The entrance back into the engine will need to be into one of the unused (currently plugged) ports on the intake.”

So does the heater valve control go on the hose to the manifold or the water pump?

[Norm B]

To the manifold. The water pump draws coolant back from the heater core. All the hoses into the pump suck.

Norm

[vtullomk4]

Thanks. Glad I checked with you guys.

[rich grsc]

Yes, as Norm said, the fitting on the pump are returns. The pump pushes water through the block. The fitting on the thermostat housing is on the 'cold' side of the flow, no heat till the thermostat opens. I would take the time to check the heater core, some have a restrictor on the OUTLET side, it slows the flow for better heat transfer.

[vtullomk4]

Ok. I’ll check. Thanks