Recent Topics
Man's best friend!
by Mad_Hatter - 08/23/19 06:53 PM
2007 Ford Fusion Cam Pics
by tig1 - 08/23/19 05:31 PM
Cloning a Lexus key
by Nayov - 08/23/19 04:23 PM
2011 GMC Acadia Shock/Strut Replacement
by panthermike - 08/23/19 03:49 PM
Confusion on oil to use on BMW 328i 2010
by goldenjava - 08/23/19 03:21 PM
Oil Confusion for 2010 BMW 328i
by goldenjava - 08/23/19 03:16 PM
ProSelect 27356 cut open
by Sayjac - 08/23/19 03:04 PM
Electrolux - Dryer reliability warning.
by pezzy669 - 08/23/19 02:37 PM
Microfiber Towels for different applications?
by Quattro Pete - 08/23/19 01:53 PM
Coated vs. painted rotors
by atikovi - 08/23/19 01:13 PM
New spark plugs, occasional misfire
by avacado11 - 08/23/19 12:34 PM
clean or replace o2 sensor?
by bionictony - 08/23/19 12:15 PM
Supertech equivalent
by Bettez88 - 08/23/19 12:06 PM
Federated OF Now Made in China
by Mr_Luke - 08/23/19 11:47 AM
Sourcing Particular Brembo Rotors
by RamFan - 08/23/19 11:22 AM
Intermittent Braking Vibration?
by Gebo - 08/23/19 10:59 AM
Northrop B-2 Spirit - First Cockpit Video
by john_pifer - 08/23/19 10:36 AM
ADBV Design - MANN Filter
by LeoStrop - 08/23/19 10:25 AM
Newest Members
goldenjava, Spuzzum, ta249, bobsauto62, Ramz
69044 Registered Users
Who's Online Now
89 registered members (80Boxcar, 4WD, 54steve, ABerns, 14 invisible), 2,028 guests, and 25 spiders.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums67
Topics293,703
Posts5,045,255
Members69,044
Most Online3,532
Jul 30th, 2019
Donate to BITOG
Print Thread
Hop To
98 Expedition heating system flow diagram #5163950 07/18/19 12:39 AM
Joined: Mar 2011
Posts: 521
F
Fitz98 Offline OP
OP Offline
F
Joined: Mar 2011
Posts: 521
My 98 Expedition 5.4 had the heater core bypassed. I was curious if it matters which side of the heater cores the inlet and outlet hoses are connected to.
Does anyone have a diagram of the heating system flow? Looking for the hose connections from the waterpump pipe under the intake to the heater core to the aux heater pipe connections and the other hose connections from the aux heater core pipe to the front heater core to the intake.
Also looking to identify which pipes and tubes are considered inlets and outlets

Re: 98 Expedition heating system flow diagram [Re: Fitz98] #5164037 07/18/19 07:00 AM
Joined: Sep 2015
Posts: 2,055
M
mk378 Offline
Offline
M
Joined: Sep 2015
Posts: 2,055
Seeing a heater core bypassed you should assume that was done because the core leaks.

The hose that goes into the back of the water pump is on the suction side of the pump, it is the return from the heater core(s).

Last edited by mk378; 07/18/19 07:01 AM.
Re: 98 Expedition heating system flow diagram [Re: Fitz98] #5164042 07/18/19 07:04 AM
Joined: Jun 2003
Posts: 19,368
C
Chris142 Offline
Offline
C
Joined: Jun 2003
Posts: 19,368
The connection thats on the intake manifold,passenger side with the restrictor in it is the pressure side. The line going to the water pump is the suction


02 Wrangler traveler sae30
87 F250 Valvoline 15w40
07 fjcruiser Chevron 10w30
Z400 castrol T 10w40
Can am maveric edge 5w40
57 case tractor Chevron sae30
Re: 98 Expedition heating system flow diagram [Re: mk378] #5164064 07/18/19 07:27 AM
Joined: Jun 2011
Posts: 1,555
W
wag123 Offline
Offline
W
Joined: Jun 2011
Posts: 1,555
Originally Posted by Fitz98
My 98 Expedition 5.4 had the heater core bypassed.
Originally Posted by mk378
Seeing a heater core bypassed you should assume that was done because the core leaks.
The more you dig into that rusty old Expedition, the more problems you are finding. I told you that this would happen Fitz. Good luck replacing the heater core, I think that the dash has to be removed to get to it.

Re: 98 Expedition heating system flow diagram [Re: wag123] #5164280 07/18/19 12:30 PM
Joined: Mar 2011
Posts: 521
F
Fitz98 Offline OP
OP Offline
F
Joined: Mar 2011
Posts: 521
Originally Posted by wag123
Originally Posted by Fitz98
My 98 Expedition 5.4 had the heater core bypassed.
Originally Posted by mk378
Seeing a heater core bypassed you should assume that was done because the core leaks.
The more you dig into that rusty old Expedition, the more problems you are finding. I told you that this would happen Fitz. Good luck replacing the heater core, I think that the dash has to be removed to get to it.

I have already replaced the heater core...twice.
A huge PITA. Less of a PITA the 2nd time, since I knew the procedure, replaced all the cracked plastic dash parts while I was at it. Dash did have to come out . First time I cheaped out and used an aftermarket core. It got a pinhole leak at the tube. That is when it was bypassed by a mechanic. 2nd time was OEM and I just guessed which was inlet and outlet side. Since I am replacing the hose, I wanted to make sure I install it in the right position while it is easily accessible.
BTW, my Expedition is definitely old, but only a few rusty parts remain. Over the years, I have done minor body work, parts replacements and painting. A little at a time is easier for me financially.

Re: 98 Expedition heating system flow diagram [Re: mk378] #5164281 07/18/19 12:34 PM
Joined: Mar 2011
Posts: 521
F
Fitz98 Offline OP
OP Offline
F
Joined: Mar 2011
Posts: 521
Originally Posted by mk378
Seeing a heater core bypassed you should assume that was done because the core leaks.

The hose that goes into the back of the water pump is on the suction side of the pump, it is the return from the heater core(s).

So would that return hose that goes to the back of the water pump also be called the outlet? The hoses online are referred as inlet and outlet.

Previous Thread
Index
Next Thread

BOB IS THE OIL GUY® Powered by UBB.threads™