X15 coolant loss

MA Arborist

MA Arborist

Branched out member
Location
Cape Cod
Anybody here with a Cummins x15 experience this?

There are no visible leaks

There is a coolant smell coming from the truck but only when running the crane and under load.

Coolant reservoir is down about a gallon after 30 or so hours of use

I’ve already googled the hell out of this topic but I’d appreciate if anyone has had experience with this issue
 
MA Arborist said:
Anybody here with a Cummins x15 experience this?

There are no visible leaks

There is a coolant smell coming from the truck but only when running the crane and under load.

Coolant reservoir is down about a gallon after 30 or so hours of use

I’ve already googled the hell out of this topic but I’d appreciate if anyone has had experience with this issue
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Is it possible that your overflow tank is leaking a small drip that runs down and burns off on the exhaust? That’s what happened to my old ISM Cummins. It’s mounted high in the year on my cabover so probably different mounting location ! I’m sure you’ve already examined all this on yours ! Just spitballing
 
MA Arborist said:
Anybody here with a Cummins x15 experience this?

There are no visible leaks

There is a coolant smell coming from the truck but only when running the crane and under load.

Coolant reservoir is down about a gallon after 30 or so hours of use

I’ve already googled the hell out of this topic but I’d appreciate if anyone has had experience with this issue
Click to expand...
I have a buddy with a rv with that engine and his rings went bad at 33k miles and 6 months out of warranty
In frame rebuild was $42k and Cummins only helped out with the repair I think it cost him $33k

I hope the best for you
Hopefully whatever it is is covered under warranty
 
Not that particular engine, but I have seen head gasket failures cause similar symptoms. If you can check the pressure of the overflow bottle, that might tell you. Sometimes if it is a head gasket you will get more pressure in the bottle than you should, or you'll see tiny bubbles coming up from the tube on the bottom of the tank. If it is overpressurizing the tank, you might see a little bit of coolant residue around the pressure tank cap where it is venting the excess gas.

You could also check the crankcase vent tube to see if there's any hint of coolant or coolant smell at the end of it, if it is a bad head gasket you might see a little hint of coolant residue or be able to smell it coming out of the vent tube.
 
Adding to the others great replies, I suggest you check your coolant Ph to check if it is 7 or lower (corrosive) and check also the last time you changed the coolant as well. Ph should be more Basic like 8.5-10. OLD coolant gets more acidic over time and can eat away.....

I was never a big fan of additives for sealing in the cooling system in my past 30+ years experience, but I have added a product called "Irontite" (All weather seal) for (small) coolant consumption issues and it worked out well in the last 3 years.

Check Ph, pressure check as Reach mentioned and check your Maintenance records on your last Flush and fill.

Consider the Irontite "All weather seal" option , when all else checks out good. 1 bottle to up to 6 gallons.
 
Can you pressurize the system when cool (put a pressure pump on the radiator) to see if you can push the leak out? I know it wasn't a Cummins diesel...but son's car was loosing coolant and I couldn't figure it out. As soon as I was at the mechanic and he pressurized it manually, the leak was obvious. That works if its an external leak. If its a head gasket...well, this would help point that direction. Does the exhaust smell different? I would expect it to if you are burning that much coolant.
 
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Head gasket - check for any milkiness in the engine oil, when its bad steam comes out the exhaust. My bet is a tiny leak that seeps at pressure/temp and evaporates immediately so you don't see it but you smell it. Best odds hose junction or weep hole on failing water pump. Maybe rad cap, less likely reservoir not under pressure. In dry season you can sometimes see dry evaporation residue at a leak site.

Also if there's one really clean spark plug (in a gas engine) moisture is being "burned" in that cylinder.
 
MA Arborist said:
Anybody here with a Cummins x15 experience this?

There are no visible leaks

There is a coolant smell coming from the truck but only when running the crane and under load.

Coolant reservoir is down about a gallon after 30 or so hours of use

I’ve already googled the hell out of this topic but I’d appreciate if anyone has had experience with this issue
Click to expand...
Cracked sleeve. Super common unfortunately. Was a cummins tech.
 
ATH said:
Can you pressurize the system when cool (put a pressure pump on the radiator) to see if you can push the leak out? I know it wasn't a Cat diesel...but son's car was loosing coolant and I couldn't figure it out. As soon as I was at the mechanic and he pressurized it manually, the leak was obvious. That works if its an external leak. If its a head gasket...well, this would help point that direction. Does the exhaust smell different? I would expect it to if you are burning that much coolant.
Click to expand...
This
 
@ MA Arborist

Further reading pointed out to me that some Cummins engines use a coolant filter. IF your X15 has a coolant filter, then the Irontite all weather seal would not be an Option.


My engines I used the Irontite on, all did not have a coolant filter.
 
The Green One said:
@ MA Arborist

Further reading pointed out to me that some Cummins engines use a coolant filter. IF your X15 has a coolant filter, then the Irontite all weather seal would not be an Option.


My engines I used the Irontite on, all did not have a coolant filter.
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I heard that the big thing with those Cummins motors. Make sure you change that coolant filter regularly.
 
Reach said:
Not that particular engine, but I have seen head gasket failures cause similar symptoms. If you can check the pressure of the overflow bottle, that might tell you. Sometimes if it is a head gasket you will get more pressure in the bottle than you should, or you'll see tiny bubbles coming up from the tube on the bottom of the tank. If it is overpressurizing the tank, you might see a little bit of coolant residue around the pressure tank cap where it is venting the excess gas.

You could also check the crankcase vent tube to see if there's any hint of coolant or coolant smell at the end of it, if it is a bad head gasket you might see a little hint of coolant residue or be able to smell it coming out of the vent tube.
Click to expand...

Brando CalPankian said:
Cracked sleeve. Super common unfortunately. Was a cummins tech.
Click to expand...
Can you tell me if it was a problem on low hour machines?
I’m under 6000 miles and a little over 1000 hrs
 
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