Removing Heaters / Looping Coolant Lines

[Dog Rescuer]

I looped the rear heat right back to the line without any extra hardware (actually, I did buy a hose clamp as an extra)

https://youtu.be/r64hHj7b9-c

I think it depends on he bus - but if you find the “line out” from the front heater and just loop that to the line going back to the radiator - it works great. My front heat and defrost work great.


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[Hay-Mad Bus]

Hey there, I have a 92 thomas (rear pushing). I have 3 heater cores total, one right by the stairs and then a middle and rear one as well. I want to remove the middle amd rear heater cores and cap the lines where they Fed into the heaters. That way we have a front heater and defroster left intact. Any recommendations on how to go about doing that?

[Twigg]

Originally Posted by Hay-Mad Bus

Hey there, I have a 92 thomas (rear pushing). I have 3 heater cores total, one right by the stairs and then a middle and rear one as well. I want to remove the middle amd rear heater cores and cap the lines where they Fed into the heaters. That way we have a front heater and defroster left intact. Any recommendations on how to go about doing that?

If the heaters were arranged in series, then simply connect the two pipes you remove at each of the two heaters.

If the heaters are T'eed off the two lines, then replace the T's with straight connectors.

I am doing exactly the same, except my bus has four passenger heaters not two. In addition, I will be re-routing the coolant lines under the bus.

[Hay-Mad Bus]

Thought about re-running the tubes under the bus as well. Just not sure the best way to do so.

[Twigg]

Originally Posted by Hay-Mad Bus

Thought about re-running the tubes under the bus as well. Just not sure the best way to do so.

I'm doing it to get them out of the cabin.

I will run them inside the frame rails. I'll insulate with pipe insulation to prevent heat loss and fasten them up with stainless steel clamps (not sure which yet).

Anyhow, that's the plan.

[Hay-Mad Bus]

I have a 92 Thomas (rear engine) and I have wires that follow the heaters hoses on the ground. Does anyone know if I can just cut those or what they might be for?

[Twigg]

Originally Posted by Hay-Mad Bus

I have a 92 Thomas (rear engine) and I have wires that follow the heaters hoses on the ground. Does anyone know if I can just cut those or what they might be for?

Mine is the '98 Saf-T-Liner, but here is how they are wired:

Running alongside the coolant pipes are flat, Romex-type wires each with 4-cores. Those carry power from the switches to the heater fans, and can be removed.

In addition, there are two more wires that come up through the floor at each heater location. According to my diagram they are grounds, and so can be removed.

There is one more wire. It runs all the way from front to back. It is the wire for the heater pump, and goes to the "Pump" switch on the dash.

If you are keeping the front heater/defroster you will want to keep that wire, but it can be re-routed any way you like.

[adic27]

Connected hoses with clamps

[MobileHolmes]

Been reading a lot of threads and cannot find a comparable situation.
My bus has a 2006 Duramax LLY. There are two shut-off valves on the engine for the coolant that goes to a heater I removed and looped. But instead of re-opening the valves I just left them shut. Is this going to cause any engine problems as far as cooling goes. The way i figure it, the coolant is being circulated by the loop at the shut off valves and doesn't need to travel to the back of the bus and come back to the engine. Right or wrong?
Thanks for any help. I don't want to fry the engine.

[o1marc]

Originally Posted by MobileHolmes

Been reading a lot of threads and cannot find a comparable situation.
My bus has a 2006 Duramax LLY. There are two shut-off valves on the engine for the coolant that goes to a heater I removed and looped. But instead of re-opening the valves I just left them shut. Is this going to cause any engine problems as far as cooling goes. The way i figure it, the coolant is being circulated by the loop at the shut off valves and doesn't need to travel to the back of the bus and come back to the engine. Right or wrong?
Thanks for any help. I don't want to fry the engine.

On the larger buses, not sure of yours, but I believe the coolant lines go to the rear heater and then exit and enter the mid heater and then continues on to the heater in the dash for defrost and driver heat. If you shut the valves you loose heat to all 3 heaters. You want to retain the front heater.

[MobileHolmes]

Originally Posted by o1marc

On the larger buses, not sure of yours, but I believe the coolant lines go to the rear heater and then exit and enter the mid heater and then continues on to the heater in the dash for defrost and driver heat. If you shut the valves you loose heat to all 3 heaters. You want to retain the front heater.

Right but I won't fry the engine while I drive until I fix the loop right? Cause i just put a temp loop on there and I need to get a secure one.

[2martins]

Originally Posted by MobileHolmes

Right but I won't fry the engine while I drive until I fix the loop right? Cause i just put a temp loop on there and I need to get a secure one.

Not an expert, but as I understand it, no, you won't. The radiator is what cools your engine, the heater hoses are just to make use of engine heat as a method of heating and defrosting.

[MobileHolmes]

Thanks so much! I’ll try and get that loop secured before I turn those valves on again.

[ekyoung]

Hey y'all. I want to re-run my coolant lines and figured I'd replace the twenty year old hoses with new ones.

Every place that sells the 1 inch house wants at least $2 a foot. I found this place that sells it at about a $1.

Is this the right stuff?!? My hose is labeled SAE 20R3 D2, just like this...


https://hosewarehouse.com/0047091615...k-standard-oem

[2martins]

Originally Posted by ekyoung

Hey y'all. I want to re-run my coolant lines and figured I'd replace the twenty year old hoses with new ones.

Every place that sells the 1 inch house wants at least $2 a foot. I found this place that sells it at about a $1.

Is this the right stuff?!? My hose is labeled SAE 20R3 D2, just like this...


https://hosewarehouse.com/0047091615...k-standard-oem

I replaced mine with 5/8ths ID hose after someone assured me that was plenty large as there are no extra heaters along the way to the front- just the driver heater and defroster.

One issue- needing to step down twice to connect the old to the new. It might be cheaper to go with 3/4 hose and only need one step size of down connectors. Ryderfleetproducts.com had the best price for dayco hose I think is what it is. I'm waiting for my connectors to arrive from homedepot online so I can hook the new ones up. They are already run where they go.

[fadderall]

Originally Posted by 2martins

Ryderfleetproducts.com had the best price for dayco hose I think is what it is.

Just bought 100' the other day from Ryder. The hose in mine is DAYCO Insulone 80319 1" Heater Hose. $1.15 per foot at Ryder. Not cheap hose but cheaper than the Gates and other 1" heater hoses I found.

QUESTION:
I have a 99 Bluebird TC2000 RE. I removed all the inside heater hose and looped the back at the engine compartment. This was before I thought about the defroster. I need this back. I got the hose. Does it matter which hose goes where or is it just a loop? In the front of my bus is still the 1" lines that used to connect to the floor inside. The lines go over to the passenger side (on the external of the vehicle under the front) and up under the dash. I assume to a heater core. There are 2 smaller ID lines that T off the 1" and go up to the small heater box under driver seat. The plan is to extend those existing 1" lines back to the engine compartment with the new 1" hose. The problem is I did not mark or even figure out which hose goes to which point in the back. Is there a way to tell? Is there a forward and return or is it just a big loop? Any help appreciated.
Thanks

DAYCO HOSE
https://www.ryderfleetproducts.com/d...ce-p-u29-80319

[fadderall]

Found a couple diagrams in the Service Manuals.
This is for 2000 Bluebird TC2000 Bus service manual


This is from 1999 Bluebird All American Bus service manual


I cant find a manual that is exactly for my bus 99 TC-2000 but these diagrams look identical and seem to match whats in my bus. I am still not exactly sure which heater hose to hook where so hopefully these diagrams can help someone help me.

BTW: Bluebird Diagrams, Manuals and Service manuals I got over here
https://www.centralstatesbus.com/manuals/

[ekyoung]

Take if FWIW I'm pretty sure outbound from engine goes through the heaters first, then back to the transmission underneath.

That said, your question would still stand: do the HEATERS have an inbound vs outbound or is does the way it loops not matter?

[ekyoung]

Sweet. Where did you get those manuals? Google presumably...but is there a clearing house of the manuals like this?

[fadderall]

Originally Posted by ekyoung

Sweet. Where did you get those manuals? Google presumably...but is there a clearing house of the manuals like this?

These guys have the Bluebird manuals you can download
https://www.centralstatesbus.com/manuals/