Engine not reaching operating temperature

[Doubeleive]

I guess my question is how is the engine supposed to heat up if it has coolant constantly running through it? My only guess is that if your using the stock radiator it will warm up like its supposed to even with coolant running through it because its a smaller hose and not a ton of coolant is running through it? I dont see how you could stop the flow other than plugging that top hose like I did. Maybe my big radiator is working too good and not letting the coolant warm up like it should. Im guessing this is some sort of overheating safety feature incase the thermostat gets stuck closed.

doubtful, the thermostat is designed to open only at a certain temperature then close again. Coolant should not be free flowing constantly unless the thermostat is stuck open. no way a bigger radiator is going to make it run any colder, nor a bigger hose. the engine creates heat and it is going to heat the coolant if it is just sitting there, the only way it wouldn't is if the coolant is free flowing and therefore never getting hot

 

[Doubeleive]

I guess my question is how is the engine supposed to heat up if it has coolant constantly running through it? My only guess is that if your using the stock radiator it will warm up like its supposed to even with coolant running through it because its a smaller hose and not a ton of coolant is running through it? I dont see how you could stop the flow other than plugging that top hose like I did. Maybe my big radiator is working too good and not letting the coolant warm up like it should. Im guessing this is some sort of overheating safety feature incase the thermostat gets stuck closed.

doubtful, the thermostat is designed to open only at a certain temperature then close again. Coolant should not be free flowing constantly unless the thermostat is stuck open (or it is getting thru somehow like you stated). no way a bigger radiator is going to make it run any colder, nor a bigger hose. the engine creates heat and it is going to heat the coolant if it is just sitting there, the only way it wouldn't is if the coolant is free flowing and therefore never getting hot

 

[Chiller449]

doubtful, the thermostat is designed to open only at a certain temperature then close again. Coolant should not be free flowing constantly unless the thermostat is stuck open (or it is getting thru somehow like you stated). no way a bigger radiator is going to make it run any colder, nor a bigger hose. the engine creates heat and it is going to heat the coolant if it is just sitting there, the only way it wouldn't is if the coolant is free flowing and therefore never getting hot

I agree. the only problem im seeing is that the bottom hose from the surge tank goes into the water pump but it goes in behind the thermostat, not in front of it. So when the pump is turning its pulling the coolant out of the engine through the radiator into the surge tank and back into the engine right behind the thermostat. i closed this loop by disconnecting the surge tank from the radiator. Now its running perfectly. How is that possible?

 

[Chiller449]

Alright i think im a little confused here. At first glance it looks like that hose that goes into the water pump from the surge tank goes behind the thermostat. What I think is actually happening is the thermostat is longer than most and can close this hole when the thermostat is closed. I think my problem is an incorrect thermostat housing for my new pump. Its allowing coolant to slip past the closed thermostat making an open loop system. Ill order a new one and see if this fixes my problem. Ill keep you guys updated.

 

[Doubeleive]

Alright i think im a little confused here. At first glance it looks like that hose that goes into the water pump from the surge tank goes behind the thermostat. What I think is actually happening is the thermostat is longer than most and can close this hole when the thermostat is closed. I think my problem is an incorrect thermostat housing for my new pump. Its allowing coolant to slip past the closed thermostat making an open loop system. Ill order a new one and see if this fixes my problem. Ill keep you guys updated.

SOME YEARS of these trucks the coolant runs through a passage on the throttle body, just a heads up if maybe someone had previously bypassed this function and then you maybe changed it.

 

[Chiller449]

SOME YEARS of these trucks the coolant runs through a passage on the throttle body, just a heads up if maybe someone had previously bypassed this function and then you maybe changed it.

Yeah I seen this on a few trucks on youtube. I don't think mine has it but ill double check. Thanks for the heads up!

 

[bottomline2000]

Unfortunately my camera is busted on my phone but ill try to explain how my hoses are ran. From the top of the pump (outlet) runs to top drivers side of radiator. Top passenger side of the radiator goes to top of surge tank (not the overflow on surge tank) Bottom of surge tank goes to an inlet on the water pump behind the thermostat. Bottom passenger side of radiator goes to thermostat housing. What I believe is happening is the pump is pushing coolant into the radiator, the thermostat is closed so it runs into the surge tank and comes out the bottom hose which runs right back into the engine because that hose goes behind the thermostat. I plugged that top hose coming off the surge tank and now the truck heats up just fine. My temp gauge stays at one line before 210 and I have excellent heat now. My check engine light also went away. Obviously this is not the correct fix and just a band-aid. Any ideas?

The hose from the surge tank should go to the front inlet of the waterpump not the rear....that hose should run to your heater core..if your hoses don't look like this they are reversed and explains why u see coolant flow in the surge tank..

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[bottomline2000]

I guess my question is how is the engine supposed to heat up if it has coolant constantly running through it? My only guess is that if your using the stock radiator it will warm up like its supposed to even with coolant running through it because its a smaller hose and not a ton of coolant is running through it? I dont see how you could stop the flow other than plugging that top hose like I did. Maybe my big radiator is working too good and not letting the coolant warm up like it should. Im guessing this is some sort of overheating safety feature incase the thermostat gets stuck closed.

Your engine does not circulate coolant unless the thermostat is open. Once the thermostat open it releases hot coolant into the radiator and the cool fluid from the radiator enters the engine. Once the cool fluid cool the thermostat enough for it to close the system closes and the engine begins to heat the fluid again until the cycle repeats. Your big radiator will only increase the cooling capacity of the system by storing more cool fluid for recovery ..the thermostat is the check and balance in the system that will prevent overcooling regardless of the size of your radiator....
Notice your heater core bypasses the thermostat which allows the cabin to get heat immediately regardless of the position of the thermostat..if you not getting heat inside you have a clogged heater core or you have improper flow to the heater core..

Sent from my SAMSUNG-SM-G900A using Tapatalk

 

[Chiller449]

The hose from the surge tank should go to the front inlet of the waterpump not the rear....that hose should run to your heater core..if your hoses don't look like this they are reversed and explains why u see coolant flow in the surge tank..

Sent from my SAMSUNG-SM-G900A using Tapatalk

Yes mine is routed just like the one pictured. Thanks for the info!

 

[Chiller449]

Your engine does not circulate coolant unless the thermostat is open. Once the thermostat open it releases hot coolant into the radiator and the cool fluid from the radiator enters the engine. Once the cool fluid cool the thermostat enough for it to close the system closes and the engine begins to heat the fluid again until the cycle repeats. Your big radiator will only increase the cooling capacity of the system by storing more cool fluid for recovery ..the thermostat is the check and balance in the system that will prevent overcooling regardless of the size of your radiator....
Notice your heater core bypasses the thermostat which allows the cabin to get heat immediately regardless of the position of the thermostat..if you not getting heat inside you have a clogged heater core or you have improper flow to the heater core..

Sent from my SAMSUNG-SM-G900A using Tapatalk

thanks for the info ill let you guys know if the new pump and matching housing work. Here is the pump im going to get. (link is to an ebay listing.)

https://www.ebay.com/itm/Gates-Engi...:ShippingMethodStandard!46360!US!-1:rk:2:pf:0

This is the only one that ive found that has a matching housing. There was one more but it had poor reviews.