Need help with SBF Heater Hose plumbing to intake manifold
Originally, my heater worked GREAT connected to the OEM SBF intake manifold on my '93 5.0L. It was the OEM hard lines that run front to back across the top of the black.
I'm currently finishing my new engine install and had to re-plumb the heater hose from the new intake.
I ran the new engine and allowed it to cycle several times, the fan kicked on about 190*+ and shut-off at 180*, but the heater never blew hot air. It took a long time for the hose going to the heater to warm up. The radiator hose heated up much quicker and got warmer.
I ran my heater hose to the port on the thermostat housing and the Water temp sensor is plugged into the port on the intake. I think the problem is this port is after the thermostat and not getting much circulation.
How have others solved this? Do I need to move the heater hose to the intake? (How? A T-fitting on the intake for temp sensor and heater? What fitting would I need for this?? (part # / link please).
A picture would be greatly appreciated.
On my 351 and 408 my heater hose went where your temp sensor is. I found another threaded hole in the intake on the other side. Intake plugs sensors.jpg
Here you can see the hose and the temp sensor. Also note the other temp sensor on the t-stat housing. If you don't have one in your housing it is a relatively inexpensive part to buy.
FFR MkII, 408W, Tremec TKO 500, 2015 IRS, DA QA1s, Forte front bar, APE hardtop.
Yes, you will need to connect the heater hose to the intake manifold in the same position as the ECT sensor in the picture. The problem with doing that is, the sensor won’t read correctly when the heater is off because it is not in the coolant flow. You will need a bypass heater control or some other method to keep the coolant circulating past the sensor. A bypass heater valve is much larger than the one supplied with the heater.
I made a bypass block that allows a small amount of coolant to bypass the heater control valve all the time. Heater output is still more than enough and it allowed me to keep the heater hoses in the stock position.
HTH
Norm
Mk4 base kit 7721, 331 Stroker, Holley Sniper EFI, Wipers, Heater, Whitby Soft Top, Drop trunk mod and more
I put the feed for my heater in the port where you have your temperature sensor. Then I put the temperature sensor in a port on the thermostat housing (https://www.napaonline.com/en/p/BK_6051080). I don't get any temperature reading for my gauge until the thermostat opens, but it's about 1 1/2 miles to get out of my neighborhood. On the drive out, I just watch for the gauge to start reading; it's always started to show temperature by the time I get to the exit. If the gauge doesn't start reading, I know I've got a problem and can turn around.
John
Last edited by phileas_fogg; 03-11-2024 at 02:32 PM.
Problem solved and heat restored!
It took visits to 2 Auto-parts stores (O'Reily's & NAPA, both were a bust) and 2 Hardware stores.
I picked up a 3/8" T at the first hardware store and a 1/4 - 3/8" bushing and a 3/8 - 1/2" nipple at the second.
All the pieces of the puzzle were acquired, then installed, and tested. I have HEAT! Success!!