Oil in coolant

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Mar 14, 2025 | 07:07 PM

David Fehir

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Oil in coolant

My dad has a 2001 Excursion with the 7.3. Last summer he was getting oil in the coolant he took the truck to a local diesel shop and had it diagnosed. They said it needed a new oil cooler so my dad had them put a new oil cooler in the truck and thinking everything was fixed he had the cooling system flushed, had a new radiator installed and got fresh coolant. Fast forward to now and he still has oil in the coolant. What could be causing this to happen? Could this be a head gasket? Or could it be something else we're missing? Please Help.

Mar 14, 2025 | 07:21 PM

Pikachu

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From: Amarillo, TEXAS!

Was it a Dorman cooler that was installed, by chance? They, along with many aftermarket suppliers, seem to have some quality issues.

Mar 14, 2025 | 07:29 PM

David Fehir

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Quote:

Originally Posted by Pikachu

Was it a Dorman cooler that was installed, by chance? They, along with many aftermarket suppliers, seem to have some quality issues.

No the Mechanic got the cooler from the local Ford garage.

Mar 14, 2025 | 10:20 PM

JSPEX

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From: Central VA

Just because the shop installed a quality part doesn't mean they did it properly. I'd be starting with double checking the cooler install, orings, etc and eliminate that possibility.

Mar 14, 2025 | 10:52 PM

David Fehir

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Quote:

Originally Posted by JSPEX

Just because the shop installed a quality part doesn't mean they did it properly. I'd be starting with double checking the cooler install, orings, etc and eliminate that possibility.

I agree however I forgot to mention that the oil cooler was changed again by the same shop roughly 2 months later. So it was gone over a second time. Sorry I didn't mean to leave that detail out.

Mar 15, 2025 | 08:07 AM

Listor

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From: Albuquerque

Quote:

Originally Posted by David Fehir

I agree however I forgot to mention that the oil cooler was changed again by the same shop roughly 2 months later. So it was gone over a second time. Sorry I didn't mean to leave that detail out.

Cup failure??

Mar 15, 2025 | 08:20 AM

David Fehir

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Mountain Pass

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Quote:

Originally Posted by Listor

Cup failure??

How do you diagnose cup failure? Im assuming you're talking about injector cups.

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Mar 15, 2025 | 10:27 AM

David Fehir

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Quote:

Originally Posted by Dan V

Probably a dumb question but I'm assuming you'd do the paper towel test when the motor is at running temperature correct?

Mar 15, 2025 | 10:39 AM

#10

z31freakify

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From: Las Cruces New Mexico

Can you ask your Pop's for a Pic of the resevoir it could just be residual oil from before.

Even when I fully flushed my cooling system using degreaser and dish soap I still mananaged to have some residual oil left, coolant is clean just have an oil line in my coolant bottle, and this was with rad off the truck with a clean fresh rebuild engine and flushed heater core.

Mar 15, 2025 | 11:13 AM

#11

David Fehir

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Quote:

Originally Posted by z31freakify

couldn't get a real good picture but I noticed when my dad stuck his finger in the tank there was oil floating on top of the coolant. This is what i got

Mar 15, 2025 | 03:29 PM

#12

z31freakify

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From: Las Cruces New Mexico

Eww thats a lot of mixing.

Maybe one of the end caps has severe pitting causing the problem? Maybe cavitation on the front timing cover (usually in the water pump area)

Mar 15, 2025 | 04:35 PM

#13

Eman85

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From: E TN

Quote:

Originally Posted by David Fehir

I agree however I forgot to mention that the oil cooler was changed again by the same shop roughly 2 months later. So it was gone over a second time. Sorry I didn't mean to leave that detail out.

So they've change the complete oil cooler twice??? Or did they reseal the cooler twice?

Mar 15, 2025 | 04:40 PM

#14

David Fehir

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Mountain Pass

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Quote:

Originally Posted by Eman85

So they've change the complete oil cooler twice??? Or did they reseal the cooler twice?

They changed the oil cooler twice

Mar 15, 2025 | 04:42 PM

#15

David Fehir

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Mountain Pass

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Quote:

Originally Posted by z31freakify

Eww thats a lot of mixing.

Maybe one of the end caps has severe pitting causing the problem? Maybe cavitation on the front timing cover (usually in the water pump area)

I talked to my dad and he said there was pitting on the end caps that they found the second time they changed the oil cooler so the mechanic changed the end caps along with the oil cooler.