Tapping/pinging from rear cylinder bank of Duratec 3.0

So, the Mariner has been out and running around for the last week and generally performing fine after swapping the replacement engine into it- we ran it to Louisville and back over the weekend where it saw both sustained highway speeds and sitting in a traffic jam in the heat with the AC on without any problems.

However, there is one concern with it- there is a very noticeable tapping/pinging/chattering coming from the rear (right-hand, from the shop manual- #1/3/5) bank of cylinders. Clearly tied to RPM (gets quicker when you rev the engine).  Honestly seems to have gotten more pronounced since changing the oil over the weekend (had put a good bit of Seafoam in with the oil initially to try and clean things out)- refilled it with the exact same kind of oil as had been in it just minus the Seafoam.

Were this a pushrod engine, I would be thinking that perhaps a lifter was stuck and not working properly- but this is a DOHC engine so I'm not sure that they would have a similar issue. I did some searching on the topic regarding the engine, and it seems that there have been issues with the FRONT bank and the exhaust cam (to which the water pump pulley mounts) cap bolts needing to be adjusted, but not with the rear bank.

When I had the engine out and going over it I didn't touch anything on the valvetrain other than changing the timing chain & guides.

So, my quandary is just what I should do about this. The 'right' way to handle it I imagine would be to pull the intake and gear such that I can get the relevant valve cover off and possibly try re-torquing the cam bearing bolts. I'm really not too keen on doing that because it will take up another day that I need to be spending on other things. And honestly we're hoping to only be keeping it for another month or two and then trading it in so the Dancer can get something newer and (hopefully) requiring less maintenance for a while.

I just driving it as it is likely going to be a problem? Is there anything that can be added to the oil to help with it? Thanks!

is it running rough?  Could the chain that runs that bank have slipped a tooth?

In reply to Fueled by Caffeine :

The engine runs perfectly as far as I can tell- runs better and more smoothly (and without any CELs) than the old engine had for a while. If it weren't making the noise I'd think everything was perfect- at higher speeds (when wind/road noise/normal engine drone are enough to overpower the tapping noise) you'd never think anything would be wrong.

From wht I have read on the giggle search, has to do with left bank noise.  Cam driven water pump.

Could it be an exhaust manifold leak?

Here's the TSB on Left bank anyway.

Engine - Ticking Noise From L/H Cylinder Head
Notes

TSB 08-3-10

02/18/08

CAMSHAFT TICK NOISE - 3.0L 4V ENGINE ONLY
WITH EXHAUST CAMSHAFT DRIVEN WATER PUMPS

FORD:
2005-2007 Five Hundred, Freestyle
2006-2007 Fusion
2006-2008 Escape

LINCOLN:
2006 Zephyr

MERCURY:
2005-2007 Montego
2006-2007 Milan
2006-2008 Mariner

This article supersedes TSB 07-13-10 to add a production fix date.

ISSUE
Some 2005-2007 Five Hundred, Freestyle, Montego, and 2006-2007 Fusion, Milan, 2006 Zephyr, 2006-2008 Escape and Mariner vehicles built 1/17/2006 thru 5/31/2007, equipped with the 3.0L 4V Duratec engine with exhaust camshaft driven water pumps may exhibit a ticking noise from the left bank cylinder head with the engine at normal operating temperature.

ACTION
Refer to the following Service Procedure to identify and resolve the engine ticking noise.

SERVICE PROCEDURE
To diagnose, with the engine running and warm (normal operation temperature), using a mechanic's stethoscope, determine if ticking noise is coming from the left hand exhaust camshaft at cylinder number 6 (Figure 1). If ticking noise can be verified, refer to the following Service Procedure.

For 2008 Escape and Mariner, check the date on the LH cam cover engine label. If the engine build date is 5/16/2007 or before, refer to the following to identify and resolve the engine ticking noise. For engines built after this date, this procedure does not apply; refer to Workshop Manual (WSM), Section 303-00.

For 2007 Fusion and Milan check the date on the front cover engine label. If the engine build date is 5/9/2007 or before, refer to the following to identify and resolve the engine ticking noise. For engines built after this date, this procedure does not apply; Refer to WSM, Section 303-00.

1. Remove the left hand camshaft cover. Refer to WSM, Section 303-01 of the appropriate manual.

2. Rotate the engine clockwise until the cylinder number 6 exhaust cam lobes are pointing up and the valves are fully closed.

3. Remove all left hand exhaust cam caps individually and reinstall them finger tight.

4. Torque bolts in sequence as shown in Figure 2, to 72 lb-in (8 N.m) excluding cam cap number 4L camshaft cap.

5. Using a screw driver positioned on each side of the top of cam cap number 4L (Figure 3), apply hand pressure and shift cam cap number 4L toward the exhaust side of the cylinder head.

6. While holding cam cap number 4L in the shifted position, torque the fastener number 9 (inboard) first, to 72 lb-in (8 N.m) then torque fastener number 10. (Figure 3)

7. Install the left hand camshaft cover. Refer to appropriate WSM, Section 303-01.

8. Fully warm the engine to verify the repair.

WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage
IMPORTANT : Warranty coverage limits/policies are not altered by a TSB. Warranty coverage limits are determined by the identified causal part.

In reply to Dirtydog :

Yeah, it's definitely coming from the right/rear cylinder bank. I've seen and read through that service bulletin, but since it applies to the other bank I'm not sure other than proving that the noise could be coming from the cams/valvetrain that it would do me much good.

It's not impossible to be an exhaust manifold leak, but it can be heard quite clearly from the top of the engine- I think an exhaust manifold leak would make it louder but not be the source of the noise. The manifold bolts are torqued pretty much to spec (that was one of the things I checked when I changed the oil). There may be a bit of a leak at the front of the flex pipe- the whole exhaust system is kind of crusty and were we planning on keeping the suv for the long term I'd be replacing much of the exhaust system- but that isn't where I'm hearing the noise from.

Didn't your old engine run quiet and just lose compression? If you still have it, the shotgun approach would be to pull the valve cover and replace all the lifters on the rear bank with some of your old ones. 

In reply to Vigo :

I think you have to pull the timing cover and chains to get the cams out =/

In reply to Matthew Kennedy :

Correct- replacing the lifters would (I believe- DOHC, which I don't understand as well as pushrod...) require pulling the cams, which to do remotely right would require pulling the timing cover and releasing the tensioner on the chain (not to mention being able to get it back properly in time).

For now, I grabbed some Rislone engine treatment and will see if that makes any difference. Not betting on it, but it can't really hurt either. Once the show is over in a few weeks and we likely start looking at a replacement for it (or, as I half expect, she decides that she wants to keep it for a while after all- though with the engine being as noisy as it is I expect it will push her more to wanting an upgrade) if it's still doing it I make have to try pulling the intake crap & valve cover and checking the torque on the cam bearing bolts.

In the past I've had better luck with Rislone then seafoam but those were all v8 or slant 6 junkers as a broke teenager...

I know the v10's are picky on the viscosity you use, not sure about the Mazda / Ford, but try a tinner oil next change.

Still having problems with this, and it's gotten worse over time. In an ideal world, we'd have been done with this and the Dancer would have a new(/er) SUV, but we don't feel comfortable moving on with that until all the financing is done for the cabin and that build is dragging on badly, so for now we're stuck with it.

I've toyed WAY more than I should with the idea of buying this and spending the time to repair it, handing it over to her to drive and then trying to fix her Mariner. Also toyed with tearing down and rebuilding the Mariner's original engine and then swapping it back in... but with more and more things going wrong with it (ABS/traction control is currently offline, pretty sure at least one front strut is on the way out...) I really don't want to spend more time/money on it than I have to...

Man, that Mariner seems like a solid flip candidate, it's so clean. But I think buying a car with a bad motor when you already have a car with some sort of motor problem seems a little off the rails. If you were swimming in spare time that would be one thing, but as busy as you guys are ... that would be rough.

My Mazda 6 wagon has the Mazda version of that Duratec 3.0. I haven't been terribly impressed with it. I'm still chasing some funky sound on it.

In reply to dculberson :

Yeah... it's a VERY low price on it, especially when I have a spare engine sitting in the garage (though they changed the engines between 2005 and 2008...). It's taking a lot of restraint to not try and grab it... it helps that the owner didn't respond to my email asking about how drivable it is (i.e., would it make the 80-mile drive home or would I have to tow it).

And yeah... we do have too much going on already. The good news being that none of the current vehicle problems are critical ones, they're all drivable, and we have the vehicles to cover everything we need to do. If the Rampage had sold I might be more seriously considering getting that older Mariner since I'd at least have an open vehicle slot, but as it is not only would it be more work than I need but it would also require the Dancer approving going over her 4-vehicle-limit rule.

If things were less busy we'd probably be out looking at potential replacement SUVs for her both to figure out what of the newer ones she likes and in the hopes the we might come across something that she loves and is reasonably-priced such that we could afford it without a loan (after trading in the Mariner).

It's also tempting to clean up the Mariner and list it and try and sell it since we'll likely get solidly more than trading it in... but it would also be a harder sell with the engine pinging and the ABS issues.