CAT 312 EXCAVATORS COOLING SYSTEM

& OVERHEATING PROBLEMS & SOLVING

 The correct hydraulic oil is SAE 10W (ISO 32) oil.

CAT 312 the best choice for the work of drains, swamps and lake clearing on the farm due to its long reach and greater track wheelbase esp with the CL and BL models. However the normal 312 are also good. some farmers prefer the early 90s models with no computer as this can be a headache when one has to have the system diagnosed.

.

COOLING SYSTEM

Check hoses if soft  & replace. You need to take the bottom plate off held by 4 bolts for the bottom radiator hose. Steam clean the motor and radiator fans etc & remove all debris esp in front of fan. Also clean the fan blades etc.
Esp from May thru to August even later always check your engine bay before starting the machine. Birds esp starlings love to build nests on the motor & most fires are caused by nests apart from arson.  Starlings can build a nest in one day & they love building on top of the radiator so grass etc will be all over the radiator space & rest on the bottom plates.

1/. Check top and bottom hoses. Use a thermometer Lazer gun to test top hose radiator to the thermostat & then the bottom hose to the water pump. The thermo hose should read around 90 degrees and rhe bottom hose less as the coolant has gone from top to bottom of the radiator doing its job & comes out less in degrees. Lazer guns are cheap around $14 -18. Check the sensor also.

Temp Sensor off Aliexpress

Check the 2x fan belts & if one is loose then you must replace both as stress on one will cause the other to break. If old looking or split also replaceas if they blow then you have water pumo problems. Our Vbelt had 108 cogs but the one below a Gates belt has a lot more as smaller cogs but OK to use. Buy from

BELTDRIVE 91 Lombard St, Palmerston North.

Phone: 06 357 2204

These belts are approx $167 for x2. Terracat = $247

With the engine running, remove the radiator cap. If it's a head gasket problem you will get bubbles in the water? A weak hydraulic pump will create heat and this can cause engine overheating.(The hydraulic cooler is in front of the radiator, thus transfering the heat to the engine) Many excavators have check valves in the cooler circuit lines, if one of these sticks you will get overheating. I've found that many heating problems in excavators are caused by hydraulic problems.
Does it have a genuine OEM temperature regulator installed.? What temp did it open at when you tested it.? The OEM P/N is 324-4128. It should open at 82 DegC.

3/. Under top hose to radiator & drain from top of tank. Have near level with top of radiator core then retighten the hose. Start the excavator & run with radiator cap for 30-45 minutes & check guage how many slots it fills on the guage. Normally small hole in thermostat will bring water to the top of radiator after heating up, Next put a load by working the machine & watch if the guage creeps up.

4/. If heating up then next check thermostat or [ regulator ] take off & put in a pot of boiling water & watch as the thermostat opens. If so then the thermostat is OK. Cost if not is $138.00 + GST.& a 3 bolt gasket they want $38 at Terracat NZ a ripoff so make your own. If you have time buy off Aliexpress. If Ok put back or replace if faulty & you can buy a themostst cheaper on Aliexpress comes with O ring. You need to buy a gasket & an O ring but its easy to make a gasket..

5/. If water pump is OK once you check the flow then fine otherwise must replace.

Best to change the thermostat as well & clean the fans of the radiator for dust, debris etc & flush the radiator.

6/. The radiator is a great place for starlings and birds to make nests and theres hardly any gap in between them to clean the radiator & the big oil cooler in front. Best to take them both out and clean & or replace if need be but you can looseb the oil cooler nuts & use a long bent air hose gun to clean. Radiators arent cheap & sometimes cheaper to buy imported from China . Common issue: theres some foam insulation on the sides of the radiator and the oil cooler & on the engine bonnet that sits between the radiator & oil cooler top. It seals the engine bay from the "radiator bay". So if this foam is not there or damaged then the fan sucks air through the gaps instead of the through the radiator and the cooler. So this can lead to the system overheating when working hard.

6 Causes of a Cold Lower Radiator Hose

1. Faulty thermostat
2. Faulty Water pump
3. Low Coolant Level
4. Air in the coolant system
5. Clogged Coolant System
6. No problem at all

Top Radiator Hose: Part No 1189921   =  161.50 + GST
Bottom Radiator Hose : Part No 1355723  = $175.02 + GST
Regulator or Thermostat: Part No: 5i8010   = $138.98 + GST

The engine has the specs stamped on the engine cover .

Always quote the serial number when buying parts.

CHECK YOUR COOLANT:

cat 312 uses Extended Life Coolant (ELC) Extended Life Inhibitor (ELI™) Diesel Engine Antifreeze Coolant (DEAC™) Natural Gas Antifreeze Coolant (NGEC™)Red coolant typically has a base of Organic Acid Technology which is designed to be more suitable for aluminium radiators.

OVERHEATING PROBLEMS

OVERHEATING PROBLEMS TO CHECK

1/. Check the coolant and flushed first. Hydraulic and engine oil levels are proper. Check the fan shrouds be sure the fan is drawing air as intended.
correct thermostat is installed it's fully open at 92 deg C thermostat valve.

2/. Check the thermostat and temp sensor & test thermostat IR Gun in a boiling pot to see if it opens & closes.These are cheap to buy & use & you can check any hot water items eg.head etc... check the temperature difference between top tank and bottom tank.if the bottom tank is too cold when compared to top tank, check for the water pump drive belt, pully, radiater could be internally clogged, thermostat etc
If it attacks aluminium you need to be doubly careful. TBH I would check the hose temps first then think about what action to take. These machines are known for accumulating debris in between the radiator and the hydraulic oil cooler which significantly reduces air flow and leads to overheating. It might pay you to pull the complete cooling package out and thoroughly clean it before proceeding further.

3/. Start the engine and run normal then use e Lazer thermometer gun to check temp of top hose to thermostat around 90F & then the bottom hose to the water pump. The bottom should be less than the top as coolant runs thru to bottom then should come out cooler.

4/. Remember you are not loading the excavator with work which will increase the temp

5/. Pays to remove the radiator and the oil cooler radiator in front and clean both while out & or replace.

6/. If still overheating then change water pump

7/. Does the turbo have a waste gate? If so, is it functioning? Inside baffles of a muffler break and get dislodged causing high back pressure.


Before throwing any parts at it I would be pulling the cooling package, splitting the radiator from the cooler and thoroughly cleaning them both.

Once that's done and back in the machine, a replacement thermostat, new fan belts, a flush of the cooling system and some decent Extended Life Heavy Duty Coolant ought to get you back on the road

FUEL CONSUMPTION

Cat 320 for 7 hours average 6 gallons per hour consumption

Cat 311- 312 - 315 Excavator On full throttle uses about 4 gallons per hour depending on the work which is 30-35 gallons in 8 hours on the hour meter.

CL on a cat excavator? is a Model designator. The C is generally stands for the the 3rd generation of that particular model machine. The L usually designates that machine as having a longer (than normal) set of crawler tracks. An example would be Cat 320CL Excavator or the 312 BL

The 312B has a 3064 turbo diesel engine producing 84 flywheel HP (FWHP). It comes standard with a power and work mode selector including a new user mode, and very good operator seat and console with longer stick.

WHERE TO BUY PARTS IN NZ:

# Mufflers made Waitara: 06 8256351

# Doors & parts Lakeland:07 3470765   0274945886  info@heavy-machinery.co.nz

Lakeland Heavy Machinery 126-136 View Rd, P.O.Box 1976 Rotorua

# Excavator World Hokitika. : 483B Hau Hau Rd, Hokitika 7811 Tel: 03-756 8020

http://www.excavatorworld.co.nz/dismantling.html

# After Market Parts & used CAT or Komatsu Parts try Machinery Specialists in

Palmerston North as they import all the time : Rex on 063568459

# Porter Group in Hamilton wreck many excavators as well. Tel: 07-849 3956

www.portergroup.co.nz

OVERSEAS PARTS:

http://www.vankeppelusedparts.com/dismantled.htm

ARE WRECKING: 2004 Cat 330cl

The 311 with swamp tracks

COBRA ATTACHMENTS is a new NZ company that sells & imports buckets and quick hitches. Check them out at www.cobraattach.co.nz or call 0800223553

We also have made in Thailand & China to your specs and can import CAT after market parts. We are having made rakes and grab rakes for these CAT 11 tonne and 12 tonne excavators.

When buying parts always quote your model and serial number as there are many variations. If you need parts etc for the 311 please ask us as we have a parts book and service manual for this model. A workshop manual can cost up to $650??? so not cheap.

If you need help check the costs for a diagnosis as not cheap:

We are preparing more pages to help farmers in NZ with maintenance & servicing etc.

CAT 311-312 [ CAB view & monitoring Spec pics ] [ CAT 311& 312 info views ]

We are also suppliers of NEW Komatsu spare parts for PCs up to 4 tonne as well looking for agents to buy our [ retread truck and bus tyres ]. RUBBER EXCAVATOR TRACKS FOR SALE all models : [ RUBBER TRACKS ] [ Kiwi bulldozer parts links ] [ Komatsu mini excavator parts ]. NZ hobby restoring [ Hitachi UH041 ] [ Excavator workshop Problems ]

WORLD WILDLIFE [ Saving Wildlife species ] [ Primate Wildlife on Myanmar /Thai Border ]

[ NZ 1080 & why ] [ Saving NZ KIWI 2024 ]

CAT 312 EXCAVATORS [ CAT 312 EXCAVATOR OVER HEATING TROUBLE SHOOTING ]

Thai International law help ask us

[ ] back to home

Email us: export@pobox.com