HEATER IS IN - BLOWING COLD AIR - HELP !!

Help Support SkidSteer Forum:

RobPg1967

Well-known member
Joined
Oct 10, 2005
Messages
45
FINALLY I have installed a twin fan heater with heater core in my Bobcat. I removed the radiator - had it cleaned and checked, heres my problem - look at the NEW picture I have posted in the pictures gallery section of this forum - look in the folder that is named " 1992 743b HEATER " The FEED line to the heater core gets hot - but the return line is staying cold. I even swapped the hoses connecting to the water pump just for kicks - and still NOT hot air from the heater. Any help will be greatly appreciated. HERES A LINK TO THE PICTURE IN CASE ANYONE NEEDS IT. http://www.skidsteerforum.com/DesktopDefault.aspx?tabid=52&gallerypage=1&currentitem=0&path=1992%20743B%20HEATER%20LINES
 

DslDan

Member
Joined
Oct 10, 2006
Messages
19
Two things I would check 1. Have you tried reversing the hoses on the heater itself? I know some heaters have a check valve built in and if its hooked up backwards what you are describing will happen. 2. You could have an air bubble in the cooling system preventing coolant from making the loop. Try starting cold and running up to temp with radiator off and see what happens. Try these two things and let us know how you make out Dan
 

RobPg1967

Well-known member
Joined
Oct 10, 2005
Messages
45
Two things I would check 1. Have you tried reversing the hoses on the heater itself? I know some heaters have a check valve built in and if its hooked up backwards what you are describing will happen. 2. You could have an air bubble in the cooling system preventing coolant from making the loop. Try starting cold and running up to temp with radiator off and see what happens. Try these two things and let us know how you make out Dan
I took a ride down the Bobcat dealer today. The head mechanic there told me that the way it shows my coolant lines connected ( in the pic ) was backwards. He suggested I run the water pump suction line to the INTAKE of the heater . I get plenty of hot air from the heater now and those hoses really get hot ! Im assuming there isnt a chance of damage / or over heating the engine with these hoses connected this way . From the heater install section of this forum - there is a post by someone that shows how to connect the hoses - I ended up getting heat ONLY when I ran these hoses the OPPOSITE than is shown in the forum install pics. DslDan - thank you for your suggestions - I always end up here when a problem happens.
 

Tazza

Administrator
Staff member
Admin
Joined
Dec 7, 2004
Messages
16,697
I took a ride down the Bobcat dealer today. The head mechanic there told me that the way it shows my coolant lines connected ( in the pic ) was backwards. He suggested I run the water pump suction line to the INTAKE of the heater . I get plenty of hot air from the heater now and those hoses really get hot ! Im assuming there isnt a chance of damage / or over heating the engine with these hoses connected this way . From the heater install section of this forum - there is a post by someone that shows how to connect the hoses - I ended up getting heat ONLY when I ran these hoses the OPPOSITE than is shown in the forum install pics. DslDan - thank you for your suggestions - I always end up here when a problem happens.
It won't damage anything, as long as fluid is moving its basically the same as having the small rubber by-pass hose still connected, but now it runs through a small radiator.
All the by-pass hose does is to allow a small amount of coolant to flow around the engine when its still too cold to open the thermostat. This way the entire engine heats up evenly, if not you will have sections (mostly the head) that will over-heat because there is no coolant flow.
Glad you got it all sorted out!
 

DslDan

Member
Joined
Oct 10, 2006
Messages
19
It won't damage anything, as long as fluid is moving its basically the same as having the small rubber by-pass hose still connected, but now it runs through a small radiator.
All the by-pass hose does is to allow a small amount of coolant to flow around the engine when its still too cold to open the thermostat. This way the entire engine heats up evenly, if not you will have sections (mostly the head) that will over-heat because there is no coolant flow.
Glad you got it all sorted out!
Rob Glad to hear you got it figured out. You didnt hurt anything having it hooked up backwards. Now just sit back and wait for it to snow and sit in your nice warm cab and watch all the grubs freeze their rears off shoveling by hand Dan
 

Tazza

Administrator
Staff member
Admin
Joined
Dec 7, 2004
Messages
16,697
Rob Glad to hear you got it figured out. You didnt hurt anything having it hooked up backwards. Now just sit back and wait for it to snow and sit in your nice warm cab and watch all the grubs freeze their rears off shoveling by hand Dan
LOL
Sit back and rub your hands making “i'm all warm and cosy” hand gestures.
 

RobPg1967

Well-known member
Joined
Oct 10, 2005
Messages
45
All I'll say about that is OOOOOOHHH YEAHHH
PICS ARE POSTED IN THE FORUM PICTURES SECTION UNDER 1992 743B HEATER LINES IN CASE ANYONE ELSE WANTS TO ADD HEAT TO A 743. I DID A VERY BASIC INSTALL WITH NO TEMP REGULATOR / ORIFICE ETC. IN THE SPRING I WILL REMOVE MY COOLANT LINES FROM THE ENGINE ( PLUG THEM ) AND RE-INSTALL THE JUMPER HOSE TO THE ENGINE.
 
Top