CAT 350 excavator overheating

CAT 350 excavator overheating

Posted in the Caterpillar Forum

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#1 Jun 23, 2008
we have a 350 Excavator, ca 1998. new rad, new fluid, new pump, new head gasket, new injectors. Still overheats and shuts off after 1 hours work. Any ideas

Since: Jul 08

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#2 Jul 7, 2008
your engine is a 3176c or C-12 right?. There should be a vent line coming from the coolant manifold (the one located on top of the cylinder head and connects to the temperature regulator) to the radiator top. check if the ventline is open. if there's no line then there should be a threaded plug on the highest point of the coolant manifold. this is where the ventline usually connects to. carefully open the plug to remove excess air from the coolant manifold. Excess air in the manifold blocks the coolant flow to the regulator and the regulator may be in such good shape that it doesnt let air through. and once the regulator is not in contact with the coolant it doesnt open. try purging the possible air from the system from the highest poit of the cooling system BEFORE the coolant temperature regulator.
also an indication of this is that the engine temperature indication you see on your Cab monitor doesnt rise as high as it used to. thats because the engine coolant temperature sensor is located on the temperature regulator housing,and, in this case, it senses the temperature of the air which may be jammed in the system. so the temp reading is way lower than the actual jacket water temp.

New Lisbon, WI

#3 Jun 8, 2009
a 350L has a 3306 not a 3176 or c12 check the thermostate ?

Since: Jul 08

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#4 Jun 9, 2009
whoa you're right, sorry for that lol.
i had a 3306 (13Z) once that had a wrong water pump impeller, it didnt generate enough pressure nor flow and led to engine overheating.

New Lisbon, WI

#5 Jun 10, 2009
could the engine be out of time ?

“B&B Diesel Service Inc”

Since: Jul 09

Houston, Tx

#6 Jul 23, 2009
how does it run? if the prv is destroking the pump it is over working the engine. will cause it to heat up even if there is nothing wrong with the cooling system. if it takes an hour there shouldnt be an overheating is merely not cooling properly....or it is under constant load and can not keep up. i always thought that little engine wasnt enough for that size of machine.

United States

#7 Apr 22, 2011
got a cat 312b overheating new everything in the coolant system. Need to know any other possible things to check to solve overheating problem. ONLY overheats when the outside temp is 75-80 degrees or higher. bout to drive me nuts! Owned it since 2000 its a 1998 model. thanks for any info

Bronx, NY

#8 Jul 25, 2011
i need to get the brochure and lifting specs for a cat 350l

Chehalis, WA

#9 Aug 28, 2011
Where is the thermostat located on a 350hp cat motor

Male, Maldives

#10 Jan 31, 2012
my caterpillar 330 bl excavators engine temperature rising after fuel pump setting done,, why engine temperature rising? engine is cat3306,, i want trouble shooting ,
jorge haro

Victoria, Mexico

#11 Apr 25, 2012
i got no power on my 350 l tracks it start going but it stop 2 seconds later what i have to check first some body nows .......

Male, Maldives

#12 Oct 2, 2012
my cat 330bl excavator has 3306TA engine, after top over hauled i m not using thermostat valve coz we have always 32c weather, the same way im using other engines, but now engine over heat afer 2 hours of work, do u have any idea?? radiator looks ok and other cooling lines ok, pls reply

Marion, IN

#13 Oct 2, 2012
You answered your own're not using a thermostat to "regulate" the engine temperature. NEVER operate ANY engine without a thermostat, you'll only shorten the life of that engine & have "mysterious" overheating problems!

A thermostat opens & closes to regulate the temperature AND the water flow. If you have no thermostat, the water is always circulating thru the cooling system at a high rate of speed. It doesn't "stay" inside the radiator long enough to "cool" itself before returning to the engine, which causes the engine to "superheat" inside. Also, when operating in colder climates, if there's no thermostat, the engine will NEVER reach the proper operating temperature. This results in excessive engine wear and causes poor fuel mileage!

Don't try to "cut corners", put thermostats in all your engines!

Male, Maldives

#14 Jan 5, 2013
hi all ,,pls any body give me an idea,, am working on cat 3306b engine,, i have replaced fuel pump,, did the timing as shop manual says,, flywheel pin and pump cam pin placed when no1 cyl tdc,but engine doesnt run properly,,i checkd afrc valve, stop solenoid,, new injectors,cleaned fuel tank n lines,primary filter checked,,no air leak found on fuel system,,but i can only start the engine if i pump fuel with hand priming pump,,but after few minutes engine stops,, no smoke found,,turbo ok,, fuel pump was ok before i fix on this engine so i dont know now the pump ok o not i changed only governer speed link it looks good ,, pls give me an idea,, am tired with this,, pls help me ,,

Hoffman Estates, IL

#15 Jan 8, 2013
cottonpicker wrote:
got a cat 312b overheating new everything in the coolant system. Need to know any other possible things to check to solve overheating problem. ONLY overheats when the outside temp is 75-80 degrees or higher. bout to drive me nuts! Owned it since 2000 its a 1998 model. thanks for any info
Did you ever get this figured out? I've got a similar problem.
Nicky 315

Ardsley, NY

#18 Feb 26, 2014
Hi guys I know posts are 2 mouths old but anyway. I have a 315bl new water pump and thermostat radiator good but still over heats???
I checked the lines after working it and the lines had no pressure and ideas. Thanks

Accra, Ghana

#19 Jul 19, 2014
Am using a 330 CL excavator and it seems the engine consumed 33 liters of fuel per hour which should not be that but rather 28 liters. so please what causes the high rate of fuel consumption.

Holyoke, MA

#20 Jul 21, 2014
My cat 235, when operating after an hour or so the water temperature tends to over heat and I have to idle down the machine for about ten minutes, so it could get back to its normal operation range. Can anyone tell me why that is?
Calvin James

Provo, UT

#21 Dec 11, 2014
How's the oil? Mine always starts to over heat when it's running low. If it's not that than your problem is beyond my pay grade! I'm not very mechanically inclined.
Buzz Aldrin

Singapore, Singapore

#22 Mar 22, 2015
I have a cat 350 and overheats only after 1 hour and after intensive inspection we suspect that the return line of the hydraulics could be the cause. There are 2 relieve valve along the return line to regulate the column of the hydraulics either back to the tank or to the radiator. What is the correct flow? We tested the temperature of the return line at different junctions and found that the pipe to the radiator is only 48degrees C whilst the oil returning direct to the tank is 70 degrees. Please help

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