My truck started leaking coolant when the temp dips into the 30s about a month or so back. Luckily around here it is only for a few days at a time overnight temps get that low.

Had this in past years and sometimes it even "cleared up" after a few dips or by just retightening a hose clamp but not so lucky this time. The amount of coolant was just more and looking at the engine it seemed to be dripping off both sides front and back. Only thing I could think of is the intake donut o-ring.

I decided after doing some research online to try and just loosen the intake and slip a new o-ring in. Got a new o-ring the other day and slowly been taking things off when I had time.

Tonight I got the o-ring in. Pretty easy but still need to get everything back in and torqued down.

I removed the intake to turbo, loosened the fan belt, removed the alternator, CAC tubes, radiator shroud, fan clutch and stator, upper idler pulley, degas bottle, and moved the FICM over. Also took the fuel lines off the upper fuel bowl.

With all that done, I loosened the intake manifold bolts and was able to use a prybar near the upper radiator hose to move the manifold up enough to get the flattened o-ring out and replace it.

The one thing that really helped was removing the upper idler pulley. With that off, I could clearly see the o-ring I was after and started to wonder if I really needed to remove the fan clutch assembly and radiator shroud.



Here's a picture of the new o-ring in place, intake not torqued down yet.




Pictures of the old o-ring. Seems pretty flat but not too bad.

Hopefully get it back together this weekend with no leaks. I have seen comments from the Ford techs getting this done much quicker like "15 minutes". I couldn't pull that off but if I can do this without pulling the turbo and disconnecting the EGR cooler I will be very happy.

Also of interest, the R99 diesel is all I can find around here. It doesn't smell like diesel fuel at all which is what I heard but had a hard time believing until today. Should make changing the fuel filters much better for me. It washed right off with soap and water, no lingering smell.

 

Got it all finished up today, test drive good with no leaks. Of course the weather has warmed up so I'll be have to wait to see how it does in the 30s.

FWIW this could be done with a little less work. Fan and stator and radiator shroud doesn't need to be removed, just upper bolts removed from the intake manifold.

You might be able to get away with leaving the fuel lines connected as there is some play there as well but easy enough to disconnect pretty quickly.

Also the alternator can just be unbolted and flopped to the side still connected. And removing the upper idler pulley gives great access to the oring.

Definitely a huge time savings over removing the intake completely.

 

Are you able to get to most of the intake manifold bolts without removing the turbo?

 

Yes. The only one that is tricky is the one under the filter assembly. For that, you need a ratcheting combination wrench, like those from GearWrench.

 

I had trouble getting to the ones in the back but a wrench did the trick. Other thing very important to torque the manifold back down in the correct sequence or you may get to do it again.

You could fill the coolant at that point and if it's leaking fix it rather than put it all back together to find a leak at the end. Don't ask me how I know.
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Happy to report temps dropped to the upper 30s last week and no leaks!

 

FRICKIN HECK........ that is one darn clean engine jeeze!