routing of heater hoses? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Daves72'GMC · 01-04-2005, 10:23 PM

Can someone please tell me the routing of the heater hoses 5/8 and 3/4 coming from the firewall(heater core) to where on the engine on a 402BB? Thank you. Dave

**kwmech** · 01-05-2005, 12:51 AM

I think the 5/8 hose will go to the water pump [return] and the 3/4 will go to the intake manifold by the t-stat housing. If you have a newer radiator, the 5/8 goes there.

JimKshortstep4x4 · 01-05-2005, 08:35 AM

The 5/8" hose goes from the top of the heater to the intake manifold. The 3/4" return hose goes to the water pump or to the radiator.

Here is a pic.

Jim

Daves72'GMC · 01-05-2005, 12:54 PM

Thanks guys ,very much for all of your help and pic really helped. Dave

da-burb · 01-05-2005, 03:03 PM

Better look again.....The correct way is 5/8" hose from the intake to the bottom 5/8" nipple on the heater core. The 3/4" nipple is at the top and that will go to the radiator or to the water pump. Any other way and the heater core is upside down.

Off topic Dave. spent a day in Asheville last spring. Toured the Blue Ridge paper mill in Canton and then the Biltmore Estates. Planning to be back next spring too.

JimKshortstep4x4 · 01-05-2005, 08:39 PM

da-burb is correct.

The heater core in the picture is upside down. I never gave it a thought when I posted the picture, I just looked at the hose routing.

Asheville is a nice place to visit. I go down every spring to visit my relatives.

Jim

01-04-2005, 10:23 PM	#1
Daves72'GMC Registered User Join Date: Mar 2003 Location: Asheville, N.C Posts: 952	routing of heater hoses? Can someone please tell me the routing of the heater hoses 5/8 and 3/4 coming from the firewall(heater core) to where on the engine on a 402BB? Thank you. Dave

01-05-2005, 08:35 AM	#3
JimKshortstep4x4 Senior Member Join Date: Jul 2001 Location: Muskegon,MI,USA Posts: 6,026	The 5/8" hose goes from the top of the heater to the intake manifold. The 3/4" return hose goes to the water pump or to the radiator. Here is a pic. Jim Attached Images

01-05-2005, 03:03 PM	#5
da-burb "Ochre Ogre" Join Date: Apr 2000 Location: Springfield, MN Posts: 3,558	Better look again.....The correct way is 5/8" hose from the intake to the bottom 5/8" nipple on the heater core. The 3/4" nipple is at the top and that will go to the radiator or to the water pump. Any other way and the heater core is upside down. Off topic Dave. spent a day in Asheville last spring. Toured the Blue Ridge paper mill in Canton and then the Biltmore Estates. Planning to be back next spring too. __________________ Bowtie Truck Stop Inc. Mid-West GM Truck Restoration Parts Supplier Your Key Parts, Auto Metal Direct, Dynacorn, and Goodmark dealer. like us @ www.facebook.com/BowtieTruckStop 1971 C-10 Suburban (Ochre) 1971 K-10 Suburban (Ochre) 1972 C-10 Suburban (Ochre) 1972 K-20 Suburban (Yellow- that just aint right!) Springfield, Minnesota 56087

01-05-2005, 12:51 AM	#2
kwmech Senior Member Join Date: Mar 2003 Location: Colfax-California Posts: 8,628	I think the 5/8 hose will go to the water pump [return] and the 3/4 will go to the intake manifold by the t-stat housing. If you have a newer radiator, the 5/8 goes there.

01-05-2005, 12:54 PM	#4
Daves72'GMC Registered User Join Date: Mar 2003 Location: Asheville, N.C Posts: 952	Thanks guys ,very much for all of your help and pic really helped. Dave

01-05-2005, 08:39 PM	#6
JimKshortstep4x4 Senior Member Join Date: Jul 2001 Location: Muskegon,MI,USA Posts: 6,026	da-burb is correct. The heater core in the picture is upside down. I never gave it a thought when I posted the picture, I just looked at the hose routing. Asheville is a nice place to visit. I go down every spring to visit my relatives. Jim



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.