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cumminsdr
cumminsdr, Mechanic
Category: Medium and Heavy Trucks
Satisfied Customers: 3653
Experience:  All types of Cummins applications
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What would cause coolant to fill overflow reservoir when

Customer Question

what would cause coolant to fill overflow reservoir when engine is not overheating in a 2010 ud 2600
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  cumminsdr replied 1 year ago.

A blown head gasket will cause your coolant to fill the overflow from the combustion gas getting into the system. When the head gasket blows out it allows cylinder combustion gas to enter the cooling system and push coolant out of the the path of least resistance. To check and confirm this there is a combustion gas in cooling system test kit that can be bought at any parts store.Please don't forget to rate my service

Expert:  Wayne replied 1 year ago.

Hi I'm Wayne

I will help you with this

What engine do you have in the Truck,

Head gasket is not always the case, hard to believe a head gasket in that new of truck

there are other factors

Let me know ,Please

Customer: replied 1 year ago.
dont know engine size its a ud 2600
Expert:  cumminsdr replied 1 year ago.

A blown head gasket IS the COMMON CAUSE and for a 5 year old unit the gasket can fail at any time will cause your coolant to fill the overflow from the combustion gas getting into the system. When the head gasket blows out it allows cylinder combustion gas to enter the cooling system and push coolant out of the the path of least resistance. To check and confirm this there is a combustion gas in cooling system test kit that can be bought at any parts store. THIS TEST MUST BE PERFORMED and if it is positive the head gasket will need to be replaced. Running the unit in this condition will cause other major issues as overheating or getting coolant in the oil. Please don't forget to rate my service.Thank you for letting Just Answer assist today

Expert:  cumminsdr replied 1 year ago.

Another cause less common is the air compressor if equipt, That only puts air in the cooling system as steady bubbles if it is pumping and would have to be isolated from the engine to test.

Customer: replied 1 year ago.
if it was head gasket would'nt there be a loss of power
Expert:  cumminsdr replied 1 year ago.

No that is not always the case. First early sign of a blown head gasket is pressure in the cooling system as it progresses you get coolant in the oil possible overheats ,the seal is still there but leaking and allowing gas to be pushed out of the damage sealing surface. If gets worse if can lead to internal engine damage

Expert:  cumminsdr replied 1 year ago.

The test to check is very inexpensive if you perform it 30.00 and 1/2 hr of your time. If a dealer gets involved that same test will cost upwards of 200.00 on top of the repair cost and their labor rate.Please don't forget to rate my service

Expert:  Wayne replied 1 year ago.

Hi

Thank you for your response and asking for me

you have the TJTA Nissan Engine 240 hp,

that is a good engine, never had Head gasket issues,

but did have air compressor issues, and crackhead between cylinders # ***** and 4

I had attended their school for 3 weeks , on rebuild, and trouble shoot

I suggest , remove the main air line from compressor

so it does not build air, if no bubbles/pressure in the system

then you know where the problem is

if this is not your issue , we will test more

Hi if this helped you

Please rate my answer 3 or more stars

If you need more info, use request button

Not Poor/Bad service

Wayne

Expert:  cumminsdr replied 1 year ago.

Hi just following up. Do you need more assistance? Please don't forget to rate my service

Expert:  cumminsdr replied 1 year ago.

Hi just following up. Do you need more assistance? Please don't forget to rate my service

Expert:  cumminsdr replied 1 year ago.

Please don't forget to rate my service

Expert:  cumminsdr replied 1 year ago.

Hi just following up. Do you need more assistance? Please don't forget to rate my service

Expert:  cumminsdr replied 1 year ago.

Hi just following up. Please don't forget to rate my service

Expert:  cumminsdr replied 1 year ago.

Please don't forget to rate my service. Thank You for allowing Just Answer to help

Expert:  cumminsdr replied 1 year ago.

Please don't forget to rate my service

Expert:  cumminsdr replied 1 year ago.

Please don't forget to rate my service.

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