2000 Excursion with the 6.8l v10 with about 132k on the clock. Just checked the oil this afternoon before this happened and it was just about smack in the middle between the high and low marks on the dipstick. As I was returning home and rolling through my subdivision, the oil "gauge" dropped to zero and the light came on. When I let off, the gauge went back up and the light went out. Rinse/repeat for the few yards to get back in my driveway. I put my real oil pressure gauge on it and started it up. On startup it was at about 70psi and then pulled back to about 60psi. When I revved the engine, the pressure dipped and then came back up a bit. I revved it more - this time to about 4k or so maybe - and the pressure just dropped all the way down to zero and I shut it down. There was a light clattering from the engine when the pressure started to drop that sounded a little bit like a rattling timing chain, but the noise went away pretty fast. When I was driving the truck before the gauge started to drop, I heard an unusual noise that I couldn't quite place but I was suspicious of maybe the A/C clutch or an accessory pulley bearing - more of a rattle than a knock. The noise stopped and it was about 3-5 minutes later that the faux gauge started acting up.

I'm running 5w30 full synthetic with a Wix XP filter and the oil isn't that old - just a bit over 2k miles and two months since the last change. I was going to attempt fresh oil and a new filter to see if perhaps there's something clogging that up (and to be able to cut open the filter and see if I've got glitter and bits).

Any hail Mary plays here or am I pulling this thing out and rebuilding it?

 

Well, the good news is that the filter was clean and there was no sheen or glitter to the oil and no shards or bits of metal in the drain pan. I tried some fresh oil and a new filter. On cold start, oil pressure started out at around 70psi and dropped down to around 60 as it warmed up. Once it was up to temp, I gave it a bit of a rev and the oil pressure went as low as about 15psi at 4,200rpm and then leveled out to around 25-30 at idle. So better than it was before an oil change, but I think the Ford spec is for about 100psi at 4k RPM. And I've never seen a motor generate less pressure at higher speeds. I'm guessing that I have one of three things going on: (1) something is blocking the pickup and it can't suck in enough oil at faster speeds; (2) the oil pump is faulty; (3) timing chain tensioners are faulty.

Looks like getting to the pickup and to the pump requires lifting the motor up in order to remove the pan. Getting to the timing chain and tensioners as well as the pump requires the front of the engine to come off. I guess I'll have to get it in to the shop and start taking things apart.

 

Sounds like the oil pump is starving for oil. Either the pickup is clogged, or it's sucking air somehow. Or - OR - the head drains are clogged, and the oil is all up in the heads. Pull the PCV and look inside while revving it.

 

Any other symptoms like a dull knocking sound?

 

I attempted to pull the breather off the left valve cover, but wound up breaking the stupid thing so looking inside will need to wait a minute. In an attempt to clean things out a bit, I put a can of Seafoam in the crankcase and ran it for a little bit. It basically acted the same way - I'm going to let it set for a little while and try again later. I also am going to go over to my shop and pick up my endoscopic camera so I can drain out the Seafoamed oil and get a look through the drain plug at the pickup to see if anything might be blocking it.

Noises.... So, this truck has always made some noises. I've put about 30k miles on it and in that time I've noticed that it has a rattling noise that always sounded like a heat shield or A/C compressor clutch. I'm investigating things much more closely now, of course, and I can sort of feel the noise vibrating on the left side valve cover. I think I need to pop that off and take a look under there. There is also a very intermittent noise that sounds like when HLAs are a little low on oil. I know this motor doesn't have lifters, but it's the same basic noise that my NA Miata makes when it's time to change the oil. What's weird about it is that it comes and goes - the motor is almost always pretty silent with the biggest noise being the injectors clicking - and that's pretty hard to hear until you stick your face next to the valve cover. The lifter-tick-esque noise fades in occasionally and then fades back out when the engine and ambient temperatures are low. It almost never happens when it's fully warmed up. It's a noise that also sounds like the mod motors sound when the manifold studs start to go so I've attributed it to an exhaust leak that seals up when with thermal expansion. but maybe that's not it. I did the plugs about 15k miles ago and torqued them to the 28ft-lbs that's recommended to avoid plug popping problems.

After putting the Seafoam in, I started it up and let it idle until the engine reached normal temp. Oil pressure was up to about 70psi at start and then settled down to 60 and then towards 50 and held pretty steady. As it was warming up, I blipped the throttle to spike the revs up to around 2000-2500 and the oil pressure climbed by about 10psi each time and then settled back down. Basically what I'd expect. Once it got up to temp, I ran the throttle up to about 4000 RPM and the pressure fell down to around 15psi. I shut it down and let it sit for about 15 minutes before re-starting it. The below video shows what that looked like, but basically after sitting for 15 minutes, it jumped right up to 48psi and held there for a bit while I let it idle. As it sat there idling it crept down slowly to 33psi. I gave it a quick rev to about 2000 RPM and the pressure jumped up to just about 40psi and then back down to 32, following the engine speed. A couple more quick revs and it would jump up, drop down, and then re-settle around that same mark. When I held the throttle at about 2000rpm for while, the pressure initially jumped up and then fell to about 20. I held the throttle steady at about 2000 for several seconds and the pressure dropped to about 18 and held for a while before dropping to about 12, so I backed off the throttle and let it idle again. This time it climbed back to only about 20psi. At this point, blipping the throttle would just keep dropping the pressure although it seemed to not drop below 14psi this time around.

If the right answer is that the oil pump is just toast, then I'll have it flatbedded over to my shop and start tearing down the front of the engine to put a high-volume Melling in there while also sending some oil off for a UOA to see what kind of metal they find in the 2000 mile old oil. I've seen more than my fair share of thrashed bearings and none of them have ever had oil that looked as good as the juice I squeezed from the pan last night, so I'm very encouraged that there isn't any fatal damage. yet. I'll do the timing service too "while I'm in there" since I've heard stories about Triton tensioners and chains. I don't know that those stories apply to the 2v 6.8, but it seems like a cheap enough bit of insurance since I've got to take the parts off the truck anyway.

On the other hand, I really don't want to go through all that just to put it back together and find out that it's still sucking air, so I appreciate the remote diagnosis help!

 

I ran my camera down the drain holes and there are no obstructions to the pan. Based on the behaviour, I'm guessing that either the o-ring on the pickup tube has failed somehow or the pressure relief valve has failed or gotten clogged. I'm going to put the valve covers back on today and let it idle for a bit more to see if pushing the Seafoam through the system some more along with some heat is enough to un-stick the valve, although I don't really expect that to work. In the meantime, I've got a parts order in for a new timing set, new serpentine set, high-volume Melling pump, and the various gaskets. I'm also going to splurge on the cam and crank tools - I've done this sort of thing with vice grips and pipe wrenches and stuff before, but the older I get the more I'm willing to spend a couple extra dollars to make it easier on myself!

Interesting point on the special tools, by the way. Ford's P/N for the cam hold down brackets is 303-557 (T96T-6256-B) and you need two. The crank holder (heh heh) is 303-448 (T93P-6303-A). OTC has tools that map to those numbers, but their catalog does not include the Excursion on the applications list for the cam hold down tool. I don't have the tool in my hand just yet, but it appears that this is an unintentional omission. Also, for some reason, OTC only sells them by the each. I guess if you only needed to remove the right side head, one tool would be all you need, but for the other 99.99% of the times you'll need to mess with the camshafts, it's fairly useless to have only one. As much as I would really like to support the home team, as it were, buying two of these things at $130 each is a bit steep when there's a set of two knock-offs for $50. I'd be willing to spend 50% more or maybe even double for the real deal, but for a tool that I'll probably only use twice in my lifetime (and that second time is extremely theoretical!), I don't think I can justify a 5x multiplier in cost.

 

yeah, the special tools thing really hits home with me. I've given up on that vice-grips thing, too

I look at it as: How much is my time worth? I could be working on this, or puttering around doing something else. I compare my hourly consulting rate (around what a good shop charges, actually) with what the tool costs, and how much time it's going to save me. So far, I have a 20ton hydraulic press from Harbor Freight (actually works very well, but the bottle jack is leaking (but not losing pressure) with less than a handful of heavy jobs on it), and a crap load of either genuine real-deal specialty tools or cheap knock offs, depending on the amount of time it saved me. Or if I found it on eBay gently used

Anyway, this ought to be interesting...

 

I learned that lesson when I went out and bought the Lisle spring-type hose clamp cable-operated pliers a couple years back. I screwed around with different pliers trying to get the return hose off a power steering reservoir for at least 90 minutes. Just couldn't quite get a bite on it that would stick and I was throwing everything I had at it. I drove up to the local Autozone, bought the tool for 20-30 bucks, and I got the clamp off with barely any work. It literally took less time to drive there, get the tool, drive back, and remove the clamp than I had spent banging my head against the stupid thing.

The other part to be concerned about here is the possibility of the cam popping loose and bending a valve. I know me. I am totally the kind of guy that would manage to knock the vice grips loose at the most inopportune moment. It'll be a little harder to do that with the proper tool!

Nothing else to report right now, other than that I got the valve cover back on and everything buttoned up and then the battery on the truck was dead, so I'm waiting on the battery charger. If it's not one thing, it's another!

 

I buttoned it back up and let it idle at temp for about 30 minutes to circulate the seafoam. It held just above 50psi for most of that time. When I started giving it some revs, it started to act normal but then under sustained RPMs it started dropping again. I guess the only other thing I can do is dump this oil and try to get a look at the pickup tube.

 

Going with worn out oil pump and leaking adjusters. The bypass spring may be broken in the pump and is hanging open under high rpm. The oil pumps are notorious for wear in the modular engines.

 

A couple follow-up questions from what I found that purports to be the factory service manual:

- Any tricks for removing the right side valve cover? They call for raising the engine up to do so. It also indicates that to R&R the oil pump, you have to drop the pan and to drop the pan you have to disconnect the transmission and raise the engine. It appears that it's a bit fiddly, but the pickup tube bolts can be gotten to with the engine in situ. Is the valve cover similar? I'm not fundamentally opposed to hooking up my hoist and lifting the motor if I have to, but if there's a decent way to go about it without, I wouldn't mind taking that route, I think.

- I don't know that I'm going to be swapping out the camshafts - there's some pitting on the left one, but it's not extreme. But investigating that a bit they call for the intake manifold to be removed to get to the cam. It doesn't really look like it's in the way at all. Although I've only looked at the left side, so maybe the difference is on the right side? That's more academic than practical because the more I think about it, I need to really resist the "while I'm in there" temptations.

- While it's out (see, there I go again...) I was going to check the balance shaft diameter and it's end play. Well, you got me, I'll check the end play before I take it out, but you get the idea. Let's pretend for a minute that I discover that the balance shaft is out of spec. Assumption number one is that if the shaft is out of spec, the caps on the head will also be out of spec since steel is harder than aluminum. Assumption number two is that if it's out of spec, there's no good way to repair that - I should be replacing the head at that point, right? I suppose I could spend a bunch of money having things welded up and turned back down but these heads aren't rare or expensive enough to do that. I don't see any type of repair kit anywhere that would put a sleeve on the shaft or anything.

So far I've got the cam and crank hold down tools, the valve spring compressor is on order to arrive tomorrow, and the parts order is in FedEx's hands which should be fine as long as they don't try to deliver it on Friday. Seriously, they have got to have a different guy driving my route on Fridays because M-Th FedEx deliveries are no problem, but every single Friday delivery from them gets screwed up. At any rate, I'm going to get it towed over to my shop tomorrow at some point so I can start tearing it down while I wait on all the parts to show up.

 

The parts shipment arrived and I spent a few minutes starting to tear in to it today. Getting the fluids drained and the radiator and shroud out was pretty easy. The left side valve cover came back out with no problem. The right side valve cover, however, is a real pain. That last bolt on the lower rear of the cover butts right up against a hard line for the A/C. Tomorrow I'll finish up pulling it off so I can see what I'm up against. I did pull the front of the valve cover up enough to see that at least one of the rollers looks pretty chewed up, so that might be the source of the intermittent ticking noise.

 

Whew. Got it all apart last night. The o-ring at the pickup tube is pretty flat, so I suspect that might be the problem with the oil pressure.

Along the way, though, the rockers and the cam are all suffering from a significant amount of pitting. I've pulled them out and I'm off to my local junkyard to get new ones. Based on the condition of those, I think that was the cause of the ticking I was getting. The balance shaft didn't look so great either, so I'm going to being home another one of those, too. That was probably the source of the gravelly noise that it always made.

When I pulled the right valve cover off, the baffle that covers the port for the pcv valve was just laying loose in the valve train. Apparently the adhesive holding it to the valve cover had just failed at some point. Maybe also a cause of some noise. I suppose it's possible that the act of removing the valve cover could have knocked it loose, but either way there are no parts of it missing so I don't think it wound up hurting anything.

The cam bores aren't great but they're not awful either. If I were building a fresh motor and had a bunch of heads from which to choose, I might not use these. But I have seen perfectly good engines with way more wear than I've got going on here, so I think this will be okay.

Edit:. Oh, and btw... There may be a way to get that right valve cover off without lifting the engine or removing the AC lines but I couldn't find it. I went ahead and popped the right motor mount nuts off and lifted the engine and the bolt got pretty easy to remove.

 

I for one appreciate the updating you've been providing, thank you.

But... Pics or it didn't happen!

 

Haha! Fair enough!

Before the pictures, I did find a way to remove the valve cover without raising the engine. Taking a sawzall to the AC condenser box and removing half of it from the truck really opens up the engine bay and gives you some room to work! That was pretty much the only way to get to the right cam and rockers at the junkyard. The bolts on the HVAC box were all corroded and weren't coming out anyway, so a little bit of surgery was necessary. Other than getting the new cams, balance shaft, and rockers - as well as scoring a battery hold down and a "new style" cupholder assembly! - the only other thing that I really finished today was cleaning up the gasket surfaces and wiping down the cam and balance shaft bores to make sure they're going to be okayish enough for me. I started to get the oil pump installed and promptly dropped one of the pickup tube bolts in to the oil pan. My magnetic pickup tool is too large to fit through there and it was late, so I'll go get a nice flexible one tomorrow when I'm fresh.

But who cares about that. Engine **** time!!



Pitted camshaft. The rollers are very similar in appearance to the lobes.

Front cover is off and getting ready to remove the timing components

Timing chain tensioners are quite sludged up.

The little pockets on the head were also full of sludge. I cleaned out these pockets and the supply holes.

Not the best cam bores I've ever seen, but I think they're okay enough to run.

Cleaned up and ready to reassemble.