John deere 7130 impossible issue please help.

Shadow_storm56

Active member

Equipment
Lawn mower
Oct 22, 2020
468
49
28
Canada

Well the new water pump definitely helped circulation alot, didn't fix my heat.... everything is improved except the air issue is somehow worse???
 

DaveFromMi

Well-known member

Equipment
L3901 RCR1260
Apr 14, 2021
610
530
93
Indiana
Is your heater above the level of the radiator? If so, it could be a candidate for a stubborn air bubble. Can you get any heater performance at max rpm?
Can you feel large or small difference in the temperature of the coolant hoses before and after the core? Hot on one side and cold on the other would indicate low or no flow with blower on high.
It's possible that a head gasket leak can cause a bubble in a high heater loop.
If the core has internal corrosion or contamination, coolant flow could be restricted. I have used Prestone flush kits on some beater cars in the past.
 

Shadow_storm56

Active member

Equipment
Lawn mower
Oct 22, 2020
468
49
28
Canada
Is your heater above the level of the radiator? If so, it could be a candidate for a stubborn air bubble. Can you get any heater performance at max rpm?
Can you feel large or small difference in the temperature of the coolant hoses before and after the core? Hot on one side and cold on the other would indicate low or no flow with blower on high.
It's possible that a head gasket leak can cause a bubble in a high heater loop.
If the core has internal corrosion or contamination, coolant flow could be restricted. I have used Prestone flush kits on some beater cars in the past.
Before the new pump I had installed a electric booster pump on the heater line which gave me heat. After the new coolant pump I still had no heat so reinstalled the booster pump. It fixed my engine circulation issue though. Earlier I had used a garden hose to flush the heater core and it seemed like no resistance so idk. Also the outlet to the heater core is hot for a bit a return is cold without using the booster.

Someone suggested maybe the valve is bad and the booster is just able to force past it? Also I think whare it's under the seat the heater core may be below or the same as the rad top in height
 

DaveFromMi

Well-known member

Equipment
L3901 RCR1260
Apr 14, 2021
610
530
93
Indiana
Any chance of a kinked hose or some other hose obstruction? Look for tight bends in the routing.
Also, check your coolant concentration. Undiluted coolant doesn't flow very well in cold weather.
I worked in the auto industry and have seen vehicle water pumps that couldn't get flow to a core. An electric water pump was needed in a couple of cases for rear seat heat.
 

Shadow_storm56

Active member

Equipment
Lawn mower
Oct 22, 2020
468
49
28
Canada
Any chance of a kinked hose or some other hose obstruction? Look for tight bends in the routing.
Also, check your coolant concentration. Undiluted coolant doesn't flow very well in cold weather.
I worked in the auto industry and have seen vehicle water pumps that couldn't get flow to a core. An electric water pump was needed in a couple of cases for rear seat heat.
Nothing kinked no and oh it's not that cold yet lol. Not even close
 

DaveFromMi

Well-known member

Equipment
L3901 RCR1260
Apr 14, 2021
610
530
93
Indiana
Where does the heater supply hose tap into the cooling system? If after the thermostat, then not much flow is possible.
Is there an engine bypass line in parallel with the heater loop?
Is the heater standard equipment or an add on?
 

Shadow_storm56

Active member

Equipment
Lawn mower
Oct 22, 2020
468
49
28
Canada
Where does the heater supply hose tap into the cooling system? If after the thermostat, then not much flow is possible.
Is there an engine bypass line in parallel with the heater loop?
Is the heater standard equipment or an add on?
It taps in on the bottom of the block and returns to the suction of the main pump. When the thermostat is open coolant has 3 possible paths. The radiator with the main lines, a little 1/2 inch line for constant circulation and the heater core lines. When the thermostat is closed it can only go to the heater core or the small circulation line. I was told the heat valve is connected to controls by a cable so we figured it's not fully opening and my boost pump plus the engine at high rpm and push past it. It's not a terrible job to get down to the heater core.