Hello, So I found some diesel in the coolant and brought to my mechanic to check the injector cups. He found a pin hole in one of the cups. I had him replace all the cups while he was in there. I am still getting some fuel in the coolant and I am wondering if its normal to have some residual fuel left in coolant loop. Does anyone have any recommendations on flushing the system or should I just stick to standard radiator spill and fill. Thanks for your time.

 

I did mine in the summer, so no worries of freezing. I ran some dishwasher detergent it it for a few days and then drain and fill with water for a week or two.

Different story if you have to worry about freezing.

 

Moved to the 7.3L PSD forum.

Stewart

 

clean & monitor or pull injectors & pressure test,is the options Ive learned here.

 

I cleaned and monitored my coolant - the fuel came back. I pulled the injectors, drained the coolant, sprayed silicone in the cups, and pressurized the cooling system with 15 PSI of air (less than 15 PSI didn't show anything):