Fuel leaking under the left front

TEXDRAG1!

MEMBER
1998 FORD E-SERIES VAN
160,000 MILES

My church has a 1998 E-350 diesel. I found fuel leaking under the left front of the van. Traced it to the coolant overflow jug. I see the antifreeze, but on top of the coolant is diesel fuel. How could diesel fuel get into the cooling system?

There is diesel fuel coming out of the lid of the coolant overflow jug after driving for 15 mins twice. I see the antifreeze in the bottom 1/4 of the jug, but the rest is diesel fuel. How can this happen. I am not a Ford diesel person, but I have been a mechanic for 30 years.

Please help.

1 Reply

SQM

MECHANIC
6,383 POSTS

Hello,

The diesel in the coolant is likely due to cracked fuel injector cups. It is fairly common issue among these diesel engines.
This due to heat and vibration of the engine overtime the cups will crack. Then the fuel will leak into the coolant.

The solution is to replace the cups (coppers) with new ones. It is suggested to replace all of them as if one is cracked now then the others will crack soon.

This will require you to remove the injectors and then replace the cups.
You will need few specialty tools to get this done in a efficient manner.

https://www.youtube.com/c/2carpros/featured

I have attached the replacement procedure include the needed special tools.

Please let me know of any questions.
Thank you.

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