Heater Hose Confusion

[JSanford]

Really confused by my heater hoses. I have the water heater preheat loop in place.
The hoses running back to the water heater preheat are 5/8" for sure.
What size hose goes from the T at the back of the manifold to the heater core?
What size hose goes from the T at the front of the engine by the water pump to the heater core?
If I need to replace both Ts what sizes do I need?

Thanks!
--
Jeremy Sanford
Sacramento, CA
1977 Kingsley
http://www.gmcmhphotos.com/photos/u42733-jsanford.html

 

 

[charles boyd]

Sir, the rear is a 5/8” inline with a 5/8” T. The front is 3/4” inline with a 5/8” T. Both are metal. Both lines going back to water
heater are 5/8”. 5/8” from rear to heater core and a 3/4” from front to heater core.

> Really confused by my heater hoses. I have the water heater preheat loop in place.
> The hoses running back to the water heater preheat are 5/8" for sure.
> What size hose goes from the T at the back of the manifold to the heater core?
> What size hose goes from the T at the front of the engine by the water pump to the heater core?
> If I need to replace both Ts what sizes do I need?
>
> Thanks!

--
C. Boyd
76 Crestmont
East Tennessee

 

[JSanford]

Thank you!

--
Jeremy Sanford
Sacramento, CA
1977 Kingsley
http://www.gmcmhphotos.com/photos/u42733-jsanford.html

 

 

[jim kanomata1]

On Mon, Oct 19, 2020 at 6:45 PM Charles Boyd via Gmclist <

> Sir, the rear is a 5/8” inline with a 5/8” T. The front is 3/4” inline
> with a 5/8” T. Both are metal. Both lines going back to water
> heater are 5/8”. 5/8” from rear to heater core and a 3/4” from front to
> heater core.
>
>
>
>
>

> > Really confused by my heater hoses. I have the water heater preheat loop
> in place.
> > The hoses running back to the water heater preheat are 5/8" for sure.
> > What size hose goes from the T at the back of the manifold to the heater
> core?
> > What size hose goes from the T at the front of the engine by the water
> pump to the heater core?
> > If I need to replace both Ts what sizes do I need?
> >
> > Thanks!
>
>
> --
> C. Boyd
> 76 Crestmont
> East Tennessee
>
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> GMCnet mailing list
> Unsubscribe or Change List Options:
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>
Almost all the coaches we work on has rubber hoses.
Am i misunderstanding?

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.gmcrvparts.com
1-800-752-7502

 

[JSanford]

Jim,

I was/am trying to figure out what size rubber heater hose goes where. 5/8" and 3/4"
--
Jeremy Sanford
Sacramento, CA
1977 Kingsley
http://www.gmcmhphotos.com/photos/u42733-jsanford.html

 

 

[CGeils]

Jeremy, whatever you do, don’t just pull the hose going to the bathroom water heater out. You must use the old hose to pull the new hose through
the floor and behind the fridge. If you just pull the old hose out, you’ll never be able to feed the new hose through by itself.
--
Chris Geils - Twin Cities / W Wa
1978 26' Kingsley w/ very few mods; PD9040, aux trans cooler, one repaint in stock colors, R134a, Al rad, Alcoas, 54k mi

 

[thomas phipps]

While you are working on these long hoses, consider installing cut off valves. Might save your engine. I had my GMC worked on by one of our
professional shops. They noticed a bubble in one of the hoses, cut it out and used a PVC spacer to jump the gap. PVC failed due to plastic fatigue, in
400 miles.
Cost one 455.
Tom
--
2012 Phoenix Cruiser model 2552
KA4CSG

 

[rgogan]

Those "bubbles" in the heater hoses that I call "aneurysms" can certainly kill engines when they burst. Please see my post on silicone hose
replacement. I have had these silicone heater hoses for 10 years and with regular thorough inspection, they show no sign of failure. They are as
supple as the day they were installed.

Remember the experience with the rubber oil fill tube that would fail and dump oil all over the ground? The problem was solved with a silicone elbow
replacement.