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Gunner41 · 08-27-2018, 11:58 PM

Hey guys,

I could use some of your expert knowledge here.

My 97 3500 7.4 is running hotter then I like. It used to hit 200 as a norm but recently its been climbing 230 as of today.
This is what I have replaced and tested. Sorry that its so long but I had to try before I bug ya'll.

Radiator-Replaced
T-stat-Replaced 180/15lbs cap
Temp sensor on L/S (Drivers)-Replaced
Water pump-Replaced
Bypass hoses (Heater)-Replaced
Cooling system-Flushed twice (Including heater core)
Rad cap-Replaced
Fan clutch-Replaced
Aux fan relay-Replaced
Pulled the Aux fan and tested directly to the battery. It works.
Now for the other items that I tried.
Turned on the A/C and tested the plug to the aux fan it worked for a min then no power at the connector going to the aux fan plug.
Tested the relay It works.
The radiator needs coolant (50/50) every two days. No puddles anywhere?
I thought the head gasket was gone but I did a block test yesterday and no its not gone.
I tested the rad system yesterday as well and it held 15 PSI.
I now heard a rumor that there is another coolant sensor next to the t-stat housing but its getting to dark right now and will have to check it tomorrow.
Does anybody know if that's correct????
What am I missing???? This thing should be frozen even here in Cali....

08-27-2018, 11:58 PM	#1
Gunner41 Registered User Join Date: May 2011 Location: San Jose, Ca Posts: 93	Coolant temp sensor Hey guys, I could use some of your expert knowledge here. My 97 3500 7.4 is running hotter then I like. It used to hit 200 as a norm but recently its been climbing 230 as of today. This is what I have replaced and tested. Sorry that its so long but I had to try before I bug ya'll. Radiator-Replaced T-stat-Replaced 180/15lbs cap Temp sensor on L/S (Drivers)-Replaced Water pump-Replaced Bypass hoses (Heater)-Replaced Cooling system-Flushed twice (Including heater core) Rad cap-Replaced Fan clutch-Replaced Aux fan relay-Replaced Pulled the Aux fan and tested directly to the battery. It works. Now for the other items that I tried. Turned on the A/C and tested the plug to the aux fan it worked for a min then no power at the connector going to the aux fan plug. Tested the relay It works. The radiator needs coolant (50/50) every two days. No puddles anywhere? I thought the head gasket was gone but I did a block test yesterday and no its not gone. I tested the rad system yesterday as well and it held 15 PSI. I now heard a rumor that there is another coolant sensor next to the t-stat housing but its getting to dark right now and will have to check it tomorrow. Does anybody know if that's correct???? What am I missing???? This thing should be frozen even here in Cali....