I know this is a 4x4 Chevy group, but a motor is a motor and I thought
someone here might shed some light on my problem. I drive a school
bus. It is a 2004 on an International Harvester frame. When it is
above 32 degrees the heat gauge reads 190. When it is 5, like here
today in Wisconsin it wanders between 165-170. All heaters are going
full blast and the passenger area never warms up. Removed the
thermostat, tested it, tested a new one and put the new one in. Same
thing. It's almost like the radiator is too big for this engine in
cold weather. Any suggestions on what else to look for and any
solutions. Lots of kids will thank you.
I would consider installing a higher temp Tstat too. ALso you need to
insulate all the water lines from engine to heater(s) and back because
a lot of heat is lost in the lines in cold weather and you want it
lost in cab area not under bus or outside the cab. The water returning
to engine from insulated lines will be warmer because less heat is
lost in path and engine will run warmer and heaters will deliver more
heat in cab. I do agree with the carboard on core itself too. When I
lived in Montana thay had a terriible time getting heat out of heaters
in diesel school buses when it was well below zero. Increasing the hot
idle speed will help a bit too because it will burn a bit more fuel
and more fuel means more heat to play with. One more thing if engine
has a fixed fan on it (no clutch) it will cool it a lot in cold
weather just from cold air being blown over engine.
What temperature thermostat are you using? Being it is a 2004, I assume it
is a 466 or 444 diesel. If so then jump over to the diesel stop and post
your message there. The diesel stop link I have posted is for 7.3l
Powerstorke diesel, which is the 444 international diesel.
If it is a gasoline engine then don't bother with TDS.
You may consider calling the outfitter (Thomas, Blue Bird, so on) and see
what they say.
Thanks for the input. All the buses we own with the Intl chassis and
body (ex All American) have the 466 engine and they stay toasty warm.
This bus has the VT365, a smaller 215 hp engine.
We did call International and their response had to do with the gate
valve for the heater control having a known problem. That effects the
heat going to the interior but doesn't answer the question about the
block not getting warm.
This afternoon I duct taped the remaining openings in the front. It
ran about 190 on my route, but the outside temp was 32. I'll see what
it does in the morning when it will be minus 5.
On Tue, 16 Jan 2007 16:50:29 -0500, "r_d"
International will not know because they just supply a running chassis to
the outfitter (American in your case) and they ones who run the heater
lines. Post a message to the link below at the diesel stop. It is for the
VT365 engine (6.0 Powerstroke engine). Some of the members are ford truck
or international mechanics. You may want to let it warm up a little (just
showing on the gauge) and feel the hoses leading to the radiator. See which
ones are warm or warmer then ambient temperature. This will give you a
hint as to where the warm coolant is going when the thermostat is closed.
Is this the first season you are having problems or has this been a constant
problem. If the bus is new to you, you may consider calling the previous
district/school. Maybe they were also having problems....
Turns out this bus, which is new to me because I just started there
(they said it was cold last winter too), has a BOOST switch. I asked
what that was for when I started and they said ignore it. Someone on
another forum mentioned that with 100 feet of heater hose the engine
wasn't strong enough to push the water that far so it needed to have
an auxilliary booster. So I turned the boost on yesterday and the
kids begged me to turn the heat down. And taping up the remaining
holes got me 20* more temp so it has been running around 190*. I
mentioned the boost thing to the boss and he said that was the only
bus that had one so they never bothered to figure out what it was.
Laughing. Yeh, I do consider them my paying customers. You give them
consideration and respect and you get it back. The big kids read
stories to the little kids. It is really a joy to be with them. Glad
they are warm now too.
First, the kids should be wearign coats and such designed for the
weather. So, if you heat the bus too much, they will sweat. And
that's much worse than being dry and cold.
Since the engine temp is dropping, you likely have too much cold
air flow over the engine. Also, the hoses from the engine to the
heater in the back may need more insulation. Foam wrap is a good
Christopher A. Young
You can't shout down a troll.
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