Another leaking valley
Thread Starter
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Cross-Country
Joined: Dec 2020
Posts: 95
Likes: 7
Another leaking valley
Diesels leak, its the nature of the beast. But when it sits for two hours and leaves a spot bigger than a half-dollar from the flywheel inspection cover, its an issue.
It has leaked since I owned it, but not this bad. Looks like its time for a repair.
I've even noticed oil splatter on my B&W turnover ball, and its only been turned over for a couple thousand miles.
This is my first diesel, but I'm not new by any means to getting dirt and fluids on my hands
I have been up in the engine bay multiple times looking for the source of the leak, every time with my phone in my hand looking at threads and trying to make sense of it all. Even after that, I can't seem to pinpoint the source of the leak.
At this point, I just need help from the experts. Where do I start diagnosing this? What can I easily remove to gain more access to the valley to see whats leaking?
Would posting photos here help?
I hope to learn some of the terminology as I go along, I'm not used to turning wrenches on these diesels.
TYIA
It has leaked since I owned it, but not this bad. Looks like its time for a repair.
I've even noticed oil splatter on my B&W turnover ball, and its only been turned over for a couple thousand miles.
This is my first diesel, but I'm not new by any means to getting dirt and fluids on my hands
I have been up in the engine bay multiple times looking for the source of the leak, every time with my phone in my hand looking at threads and trying to make sense of it all. Even after that, I can't seem to pinpoint the source of the leak.
At this point, I just need help from the experts. Where do I start diagnosing this? What can I easily remove to gain more access to the valley to see whats leaking?
Would posting photos here help?
I hope to learn some of the terminology as I go along, I'm not used to turning wrenches on these diesels.
TYIA
FTE Leadership Emeritus
Joined: May 2014
Posts: 27,355
Likes: 5,947
From: Lake Hartwell, GA
I had the passenger side HPOP head fitting leak on me for months. It eluded me because I thought for sure it was a pedestal o-ring until I bought an endoscope and realized the oil was not coming from the pedestal o-rings. A quick 1/8 turn of the fitting and good to go!
You need to clean the valley and valve covers the best you can. Then, see if oil is pooling in the valley. If so, is it toward the front or the firewall? Go from there... If the oil is coming from the back of the engine, it may be a rail plug, if it is coming from the driver lower side, maybe the oil cooler. There is a valley drain on the passenger side under the turbo, so just because you see oil underneath does not mean the source of the leak is underneath.
There are a lot of places for oil to leak, you just have to narrow it down to an area and we can help you from there.
You need to clean the valley and valve covers the best you can. Then, see if oil is pooling in the valley. If so, is it toward the front or the firewall? Go from there... If the oil is coming from the back of the engine, it may be a rail plug, if it is coming from the driver lower side, maybe the oil cooler. There is a valley drain on the passenger side under the turbo, so just because you see oil underneath does not mean the source of the leak is underneath.
There are a lot of places for oil to leak, you just have to narrow it down to an area and we can help you from there.
Thread Starter
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Cross-Country
Joined: Dec 2020
Posts: 95
Likes: 7
I had the passenger side HPOP head fitting leak on me for months. It eluded me because I thought for sure it was a pedestal o-ring until I bought an endoscope and realized the oil was not coming from the pedestal o-rings. A quick 1/8 turn of the fitting and good to go!
You need to clean the valley and valve covers the best you can. Then, see if oil is pooling in the valley. If so, is it toward the front or the firewall? Go from there... If the oil is coming from the back of the engine, it may be a rail plug, if it is coming from the driver lower side, maybe the oil cooler. There is a valley drain on the passenger side under the turbo, so just because you see oil underneath does not mean the source of the leak is underneath.
There are a lot of places for oil to leak, you just have to narrow it down to an area and we can help you from there.
You need to clean the valley and valve covers the best you can. Then, see if oil is pooling in the valley. If so, is it toward the front or the firewall? Go from there... If the oil is coming from the back of the engine, it may be a rail plug, if it is coming from the driver lower side, maybe the oil cooler. There is a valley drain on the passenger side under the turbo, so just because you see oil underneath does not mean the source of the leak is underneath.
There are a lot of places for oil to leak, you just have to narrow it down to an area and we can help you from there.
Hotshot
Joined: Jul 2008
Posts: 12,782
Likes: 2,142
From: N.GA Mountains
The only thing you need to avoid getting wet is the fuse/relay boxes on drivers side near firewall.
Also, there is no reason for your diesel to leak anything. It is FALSE that ‘all diesels leak’.
There are several common leak spots and they are all cheap and easy to fix. When engine is clean and dry, you’ll be able to look in some specific spots and find your problem. I use pressure washer and then blow it dry with leaf blower and/or compressed air. Sometimes hitting stubborn or suspicious spots with brake cleaner.
Good luck and keep us posted.
Lead Driver
Joined: Oct 2005
Posts: 6,129
Likes: 1,919
From: Ponca City, OK
If it looks like it's coming from everywhere and nowhere, then high pressure oil system is a likely culprit. The oli line fittings at the pump and heads are prone and common like Sous said, also the non serviceable plug can be a tough one to track down due to location.
More Turbo
Joined: Mar 2009
Posts: 506
Likes: 5
From: South Florida
I had the passenger side HPOP head fitting leak on me for months. It eluded me because I thought for sure it was a pedestal o-ring until I bought an endoscope and realized the oil was not coming from the pedestal o-rings. A quick 1/8 turn of the fitting and good to go!
You need to clean the valley and valve covers the best you can. Then, see if oil is pooling in the valley. If so, is it toward the front or the firewall? Go from there... If the oil is coming from the back of the engine, it may be a rail plug, if it is coming from the driver lower side, maybe the oil cooler. There is a valley drain on the passenger side under the turbo, so just because you see oil underneath does not mean the source of the leak is underneath.
There are a lot of places for oil to leak, you just have to narrow it down to an area and we can help you from there.
You need to clean the valley and valve covers the best you can. Then, see if oil is pooling in the valley. If so, is it toward the front or the firewall? Go from there... If the oil is coming from the back of the engine, it may be a rail plug, if it is coming from the driver lower side, maybe the oil cooler. There is a valley drain on the passenger side under the turbo, so just because you see oil underneath does not mean the source of the leak is underneath.
There are a lot of places for oil to leak, you just have to narrow it down to an area and we can help you from there.
FTE Leadership Emeritus
Joined: May 2014
Posts: 27,355
Likes: 5,947
From: Lake Hartwell, GA
I bought the camera in the link below based on the review and recommendations from a couple of other FTE'rs. The 2.7K video was a bit more choppy than I had expected, but I think that had something to do with the engine vibration and me trying to hold the camera with it snaked into the valley and to the pedestal o-rings.
Once I got it dialed in, it worked quite well.
In the link below, you can see the T4 pedestal to engine block joint very clearly was not the source of the leak.
https://www.ford-trucks.com/forums/1...l#post19407445
The scope saved me quite a bit of work and effort and I am grateful the fellas helped me make that purchase. They are good at that sort of thing.
Once I got it dialed in, it worked quite well.
In the link below, you can see the T4 pedestal to engine block joint very clearly was not the source of the leak.
https://www.ford-trucks.com/forums/1...l#post19407445
The scope saved me quite a bit of work and effort and I am grateful the fellas helped me make that purchase. They are good at that sort of thing.
Trending Topics
Lead Driver
Joined: Dec 2006
Posts: 7,093
Likes: 147
From: San Diego, CA
I recommend doing your inspection with the truck idling.
I had an HPOP fitting o-ring give out on me and couldn't find it for the life of me ("coming from everywhere and nowhere"). I started the truck and let it idle when I checked under the hood and it was very easy to spot as oil was streaming out of that fitting.
Most likely it's coming from on top of the engine but also check the oil dipstick adapter fitting on the passenger's side of the oil pan. Many of us have had issues with that fitting as well.
For on top of the engine (from another thread):
There are three 'pockets' - front, middle, and rear - in the valley. Look to see which forward-most pocket has oil.
Here's a rough idea of what could be the culprit(s):
Front - high pressure oil (pump, sensors, fittings)
Middle - block fittings
Rear - tubo, exhaust backpressure valve, fittings
If you can't tell exactly where it's coming from start the truck and take a good look on top with a flashlight and inspection mirror while it's idling.
I had an HPOP fitting o-ring give out on me and couldn't find it for the life of me ("coming from everywhere and nowhere"). I started the truck and let it idle when I checked under the hood and it was very easy to spot as oil was streaming out of that fitting.
Most likely it's coming from on top of the engine but also check the oil dipstick adapter fitting on the passenger's side of the oil pan. Many of us have had issues with that fitting as well.
For on top of the engine (from another thread):
There are three 'pockets' - front, middle, and rear - in the valley. Look to see which forward-most pocket has oil.
Here's a rough idea of what could be the culprit(s):
Front - high pressure oil (pump, sensors, fittings)
Middle - block fittings
Rear - tubo, exhaust backpressure valve, fittings
If you can't tell exactly where it's coming from start the truck and take a good look on top with a flashlight and inspection mirror while it's idling.
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Thread Starter
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Cross-Country
Joined: Dec 2020
Posts: 95
Likes: 7
Got it all cleaned up and watched it for a bit, but no leak yet 
gonna go to the auto parts store and get me an inspection mirror and ill drive the truck, when I get home I'll look again with the mirror.
thank you all for the help so far
gonna go to the auto parts store and get me an inspection mirror and ill drive the truck, when I get home I'll look again with the mirror.
thank you all for the help so far
Thread Starter
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Cross-Country
Joined: Dec 2020
Posts: 95
Likes: 7
Using this diagram, I found a weep coming from what seems to be the end of the IPR valve. I tried my best to attach a picture.
And evidence of a weep from the non-removable plug... but there's evidence of a weep everywhere I couldn't fit the power washer lol
Tempted to remove boost pipes to get a better look at the turbo pedestal.
Currently not enough oil leaking to see a pooling of it.
Lead Driver
Joined: Oct 2005
Posts: 6,129
Likes: 1,919
From: Ponca City, OK
I try to never say never, but it would require some very unusual circumstances for an IPR valve to leak there. It is much more likely that the passenger hose fitting is leaking and dripping onto the IPR then oozing under the solenoid and along tube then out at the tin nut there.
Thread Starter
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Cross-Country
Joined: Dec 2020
Posts: 95
Likes: 7
I try to never say never, but it would require some very unusual circumstances for an IPR valve to leak there. It is much more likely that the passenger hose fitting is leaking and dripping onto the IPR then oozing under the solenoid and along tube then out at the tin nut there.
I'd like to add that I took the pipe off that goes from the intercooler to the intake (the one on the passenger side) to get a better look at the turbo pedestal, and I didn't see anything except a bunch of crud on the fuel return line and the back of the passenger side head I missed. Turbo pedestal looked clean. I'd like to mention that there was a bunch of crud on the intake side of the turbo, and its still on the backside of the turbo because I couldn't get to it to clean it. Is that just from the CCV?
I'll still be checking in here to see what yall have to say, but in the meantime I'm going to drive it around for a few days and then check again.
Thank you all for the help thus far.
Logistics Pro
Joined: May 2017
Posts: 4,667
Likes: 1,455
From: Muskogee, Ok
So, while it's clean, I'd stuff a bunch of wadded up ***** of paper towels in the valley, then drive around doing your daily errands. Then start pulling out the individual wads, then if you find one with oil you know where to look for your leak
Thread Starter
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Cross-Country
Joined: Dec 2020
Posts: 95
Likes: 7
Thank you!
Hotshot
Joined: Jul 2008
Posts: 12,782
Likes: 2,142
From: N.GA Mountains
Clean suspect areas with brake cleaner.
Basically, every arrow in your picture above is a suspect. Look at all of those ORB fittings for evidence of o-ring splayed out around it - a dead give away the o-ring is shot.
The caked up oil is likely just years of oil weeping out of the CAC boots. I find it takes a few sessions of degreaser and p-washer to get a neglected engine cleaned up. Next time, start where you see it’s still dirty. Also, take a step stool to the car wash so you can really get up in there and blast from as many angles as possible.
The clamps on fuel lines in the valley are also suspects. Just remove them anyway so they don’t wear a hole in the fuel lines.
Basically, every arrow in your picture above is a suspect. Look at all of those ORB fittings for evidence of o-ring splayed out around it - a dead give away the o-ring is shot.
The caked up oil is likely just years of oil weeping out of the CAC boots. I find it takes a few sessions of degreaser and p-washer to get a neglected engine cleaned up. Next time, start where you see it’s still dirty. Also, take a step stool to the car wash so you can really get up in there and blast from as many angles as possible.
The clamps on fuel lines in the valley are also suspects. Just remove them anyway so they don’t wear a hole in the fuel lines.