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Cat 257B Temp problem

Guyute

Member
Joined
Jul 26, 2008
Messages
19
Location
Vermont
Occupation
Excavating, owner operator
I have a 257B with 1157 hrs.

The Temp warning light keeps flickering and sometimes the alarm goes off.
I have put in a new thermostat, water pump and have made sure that they are both working properly. Any thoughts, cat guy said to run it as it may be just a faulty sensor and they can come look at it next week. It does not smell hot nor is it loosing coolant.
Anybody ever experience this problem, I am about ready o throw a match under this heap after 6k in repair this summer. On the plus side I have a 90% new undercarriage.
Thanks in advance, John.
 

Hardline

Senior Member
Joined
Nov 29, 2009
Messages
340
Location
Waxahachie Texas
Occupation
Small business owner
John pick yourself up an infra red pyrometer. They are handy to have and you can just point and shoot to see if it is actually getting hot or not. Had a 236B that had an oil pressure sensor that was doing the same thing. At idle it would flicker and the customer was concerned he was loosing pressure. Installed a manual gauge test gauge and determined that the sensor was bad.
 

JeremiahSr

Well-Known Member
Joined
Sep 10, 2010
Messages
204
Location
Houston, Tx
Occupation
Vice Pres./General man./Technician
Check the connection at the switch. This should be on the thermostat housing. If it looks good it wouldn't cost much to change it to not have to pay field mechanic for such an easy job. If this is your engine S/N CYP1-UP; CYS8300-UP PART OF 292-5719 ENGINE AR-PRIMARY..............
the part number is: 341-3600 cost $49.68 at my local cat parts store.
If it is different give me your engine serial and arrangement number i will give you the sender part number. Good luck.
 

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kirby ward

Member
Joined
Oct 12, 2020
Messages
7
Location
Arkansas
I have a 257B with 1157 hrs.

The Temp warning light keeps flickering and sometimes the alarm goes off.
I have put in a new thermostat, water pump and have made sure that they are both working properly. Any thoughts, cat guy said to run it as it may be just a faulty sensor and they can come look at it next week. It does not smell hot nor is it loosing coolant.
Anybody ever experience this problem, I am about ready o throw a match under this heap after 6k in repair this summer. On the plus side I have a 90% new undercarriage.
Thanks in advance, John.
Did you ever put a new sensor in and if so did it fix it, mines doing the same thing, I just bought it from Missouri and it started doing this in the first hour?
 

Nige

Senior Member
Joined
Jun 22, 2011
Messages
32,128
Location
G..G..G..Granville.........!! Fetch your cloth.
Seeing as you have no previous history with your machine the first thing I would suggest before loading the parts cannon is to check with an infra red heat gun whether or not you actually have a high temperature problem or not. Take the temperature on the thermostat housing and post your results. If you want an illustration or two to show you where to do this then please post a Serial Number.
 
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