6.7 Cummins; Coolant in oil; engine mods

[LeonardA]

I have a 2018 Ram with the 6.7 Cummins. At 140k miles I got a code that DPF was at capacity. I contacted a DPF cleaner that told me that he could clean my DPF but he suspects we’ll find coolant in the DPF indicating a problem upstream.

I chose to delete the EGR and DPF. While doing this it was noticed that the coolant reservoir was a little low. I was told that the low coolant was likely due to a failing EGR (also causing the DPF problem). I’ve been worried that it may be a head gasket.

I sent in an oil sample with 7500 miles on it (5500 pre egr delete and 2000 post delete). The oil analysis showed high potassium (130). The lab indicated coolant in the oil.

I replaced the oil with T6. I took a sample at 1200 miles. This time the potassium is at 17 and the lab does not indicated coolant in oil.

Can I conclude that the EGR removal solved my coolant problem? Is 17 potassium too high for only 1200 miles?

 

[OLEJOE]

It’s probably residual left from the last oil change. Run it longer and see if it increases.

 

[tnt_motorsports]

I agree with @OLEJOE on run it longer to see if it changes.

Be aware that your tuning will be a big factor on if your HG lives. There is lots of info out there on other forums regarding this. Hopefully you have a good tune.

Just my $0.02

 

[LeonardA]

It’s probably residual left from the last oil change. Run it longer and see if it increases.

Thank you.

I wondered if 17 was a normal scout of potas

I agree with @OLEJOE on run it longer to see if it changes.

Be aware that your tuning will be a big factor on if your HG lives. There is lots of info out there on other forums regarding this. Hopefully you have a good tune.

Just my $0.02

Thank you

I’ll do some research on my tune as it relates to head gasket.

When I had the work done I asked if upgrading my head bolts was necessary. He said that it wasn’t based on my driving habits and if I kept the switch on the low hp setting.

I’ve heard conflicting info on whether the EGR can allow coolant into the engine. I’m hoping that was the case.

I’ll try to be patient and wait until 7500 to check again. My coolant level appears to have remained at the same level since deleting the EGR, but I don’t know how much coolant ends up in the engine with a HG issue.

Thanks again

 

[LeonardA]

It’s probably residual left from the last oil change. Run it longer and see if it increases.

It’s probably residual left from the last oil change. Run it longer and see if it increases.

I will. Thank you for your reply!

 

[cptbarkey]

Can I conclude that the EGR removal solved my coolant problem? Is 17 potassium too high for only 1200 miles?

Pretty likely only residual that didnt drain out. Its impossible to drain it completely. Good job with the fix. For 100% certainty do a shorter OCI and retest.

 

[LeonardA]

Pretty likely only residual that didnt drain out. It’s impossible to drain it completely. Good job with the fix. For 100% certainty do a shorter OCI and retest.

When should I get another sample? My original that had 130 potassium was 7500 miles. My second sample that showed 17 was 1200 miles.

A very confident “Cummins specialist” told me that it’s impossible for coolant to get into the engine through the EGR so it must be a head gasket. But I’ve read otherwise.

Thank you for the help!

 

[cptbarkey]

When should I get another sample? My original that had 130 potassium was 7500 miles. My second sample that showed 17 was 1200 miles.

A very confident “Cummins specialist” told me that it’s impossible for coolant to get into the engine through the EGR so it must be a head gasket. But I’ve read otherwise.

Thank you for the help!

Up to you, as long as trend goes down that is what matters

 

[tnt_motorsports]

Thank you.

I wondered if 17 was a normal scout of potas

Thank you

I’ll do some research on my tune as it relates to head gasket.

When I had the work done I asked if upgrading my head bolts was necessary. He said that it wasn’t based on my driving habits and if I kept the switch on the low hp setting.

I’ve heard conflicting info on whether the EGR can allow coolant into the engine. I’m hoping that was the case.

I’ll try to be patient and wait until 7500 to check again. My coolant level appears to have remained at the same level since deleting the EGR, but I don’t know how much coolant ends up in the engine with a HG issue.

Thanks again

Go look at the Cummins forum. Lots of good info on blown HG. Typical symptoms are erratic temperature gauge and bubbling over flow bottle that pukes coolant.

Most times a blown HG on a 6.7 doesn’t put coolant in the oil. Also with the EGR cooler failure it usually goes to the exhaust and is “burnt” in the exhaust.

You might need to keep an eye for a different failure. Again I’d test at 2,400 miles and see what it says. $40 for a UOA is minor compared to major engine repairs.

Just my $0.02

 

[LeonardA]

Go look at the Cummins forum. Lots of good info on blown HG. Typical symptoms are erratic temperature gauge and bubbling over flow bottle that pukes coolant.

Most times a blown HG on a 6.7 doesn’t put coolant in the oil. Also with the EGR cooler failure it usually goes to the exhaust and is “burnt” in the exhaust.

You might need to keep an eye for a different failure. Again I’d test at 2,400 miles and see what it says. $40 for a UOA is minor compared to major engine repairs.

Just my $0.02

Thank you. I’m at 2440 right now.

Last sample I got was from loosening my drain plug. Is this ok or should I be pumping it through the dipstick? Or drain the oil and get it midstream?

Thanks again

 

[tnt_motorsports]

Thank you. I’m at 2440 right now.

Last sample I got was from loosening my drain plug. Is this ok or should I be pumping it through the dipstick? Or drain the oil and get it midstream?

Thanks again

When I have samples mid oil change I drive the truck to get it warmed up and stick a hose down the dipstick tube.

Just my $0.02