heater hose routing?

[shifts13]

i already tried searching but didn't really find anything
I got a '90 S13 w/ a S13 blacktop
my first question is, how do the heater hoses connect to the firewall from the engine?right now i have the hose coming off the intake mani connected to the upper outlet on the firewall, and the house coming off the block to the bottom. does it really matter which goes to which?

and finally, will a RHD heater core fit on my car?

im asking because im not getting any hot air at all. I just noticed it a few days ago. It was blowing hot air before, so I'm guessing its the heater core.
Thanks!:bigok:

[Sileighty_85]

your hoses routed sound fine but if your not getting any hot air out then its probably your heater By-Pass Valve is not opening

as for the Heater core Im pretty sure it wont fit due to hose configureation for the RHD

[miravete]

the rhd heater core wont fit on your LHD car. trust me on that one.

[g6civcx]

ihow do the heater hoses connect to the firewall from the engine?

You need to search my posts. I described this problem in detail.

Pull up a coolant circulation diagram for an SR. You will see that coolant flows from the intake manifold area into the heater core inlet with control valve, out the heater core and back to the block.

The return line will mate up with the block around the back of the firewall area where the turbo coolant return line also goes.


does it really matter which goes to which?

Yes. You need the inlet to go into the heater core fittings with the control valve on it. If you installed it backward, coolant won't circulate correctly through the engine.

and finally, will a RHD heater core fit on my car?

If you tried to installed one you would know. The heater core is on the wrong side. Even if you tried installing it in the heater box it would not fit correctly.

im asking because im not getting any hot air at all. I just noticed it a few days ago. It was blowing hot air before, so I'm guessing its the heater core.

Do yourself a big favor and convert the heater core fittings on the block to 5/8". JDM fittings are 3/4". Trying to push a 5/8 hose over the block fittings = leak. Trying to do some conversion = leak.

Route the hoses correctly like said above. Raise the front end as high as you can. Pull the heater control to full hot. With the engine running, loosen the heater hose slightly and quickly retighten it. Air bubbles will come out and allow coolant to flow to the heater core.

Bleed the cooling system again.


Whatever you do, stay away from the Heavy Throttle heater hose kit. The S hose is 3/4" all the way through = leak at the heater core. Search my posts for Gates part number if you want to put together a kit for yourself.