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cat 299d2 xhp overheating

AO299D

Well-Known Member
Joined
Nov 14, 2019
Messages
52
Location
Ontario
any ideas what to check yet or how to pin point if engine thermostat needs to be changed when engine overheats i checked the belt, coolant(it does need about a 2L in 5 hrs time and i dont see any leaks) and rad looks clear when i shine a light through. DX200752 is S/N
 

Nige

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Jun 22, 2011
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G..G..G..Granville.........!! Fetch your cloth.
Before believing everything you seen as regards warning lights on the panel have you used a non-contact thermometer to check the temperatures of the coolant hoses into and out of the radiator when the high temp alarm is going off..?

Personally I would've though the thermostat was the least likely possibility of what's a fault.
 

Nige

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Jun 22, 2011
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G..G..G..Granville.........!! Fetch your cloth.
Your comment about 2L of coolant loss every 5 operating hours with no obvious external leaks does not fill me with happiness..........

Try having an oil sample analyzed, specifically for the presence of water and/or coolant. If the test result is positive for either one or both of them then it's most likely engine out time.
 

partsandservice

Senior Member
Joined
Feb 14, 2011
Messages
846
Location
Georgia
Is this an EGR engine? If so I would look at the EGR cooler for the coolant loss and engine over heat. Also it seems if the water level ever gets low enough to let air in the cooler when the engine is hot the cooler will crack almost every time. I always look for another coolant leak when I am dealing with a cracked cooler
 
Last edited:

AO299D

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Joined
Nov 14, 2019
Messages
52
Location
Ontario
yes i changed the cooler last summer but maybe it cracked again that would be internally and not visible from the outside right?
 

Nige

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G..G..G..Granville.........!! Fetch your cloth.
To have 2L of coolant disappearing without visible trace in a system that only holds 15.5L total is more than worrying. You have about 15% of the system capacity going AWOL in the equivalent of less than half a day's work...........
 

sjspecialty

Member
Joined
May 19, 2020
Messages
7
Location
NJ
Our 299D2 XHP overheated as soon as you tried doing any real work with it as soon as we took delivery of the new machine from the dealer. We found an oring and backup rings in the hydraulic reversing cartridge valve had come out of the spool and lodged in the reversing valve for the hydraulic fan. With the cooling fan running in reverse was inadequate to cool the machine and the hydraulic flow was severely restricted when the fan tried to run in forward. I doubt you have the exact same issue but it is probably worth checking that the reversing function is working properly and may check to see if the radiator is clean and the fan is operating at the proper speed.

IMG_1009.JPG
 

KSSS

Senior Member
Joined
Feb 27, 2005
Messages
4,319
Location
Idaho
Occupation
excavation
To have 2L of coolant disappearing without visible trace in a system that only holds 15.5L total is more than worrying. You have about 15% of the system capacity going AWOL in the equivalent of less than half a day's work...........


The times I have had a similar issue (05 5500 Duramax) it was a head gasket issue. Pop the cap off the radiator and if it built pressure that might be the problem.
 
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