Tapping noise, front of engine

[Mooney 78865]

Preamble:
50,003 miles on a 2014 F53 chassis with the 6.8l 3 valve V10
There are no codes, no check engine light, runs great and the engine was quiet when we put it in storage.
The coach had been sitting for about 5 months due to medical issues. When I started it up there was an immediate "Ticking/Tapping" sound. Initially I thought it was one of the valve lash adjusters had pumped down due to the prolong sit. It never got any better after driving for a few miles. Went to the house and brought out a stethoscope, removed the inside motor cover and started listening. For the life of me I could not determine which side the tapping was coming from.
So, here is what I have done to date.
1. Added Riselone engine treatment and drove about 80 miles
2. Changed oil and filter (Motorcraft filter)
3. Drove another 100 miles
4. Pulled the plugs, inspected the plugs and coil packs (None of the plugs were loose, coil packs look new)
5. Removed the valve covers and rotated the engine by hand removing and inspecting the roller rockers and pressing down on the lash adjusters for movement. All lash adjusters appear to be fine, all of the roller rockers are fine.
6. Removed the serpentine belt and ran the engine to check for a bad pulley or whatever.
7. Checked the manifold bolts. I found both studs broken on the #5 cylinder. (upon initial visual inspection they were there being held in by rust)
8. Replaced the broken studs and all other studs on that bank with stainless steel
9. Removed the serpentine belt again and ran the engine this time using the stethoscope listening to the front of the motor.
10. I saw where the intake runner control module would cause tapping, so I unplugged it and started the engine, no change. I'm not sure if that is a way to check it but it's what I did. Again, the engine runs fine with no codes.
To summarize, nothing I have done, inspected, touched or fiddled with has changed a thing. The tapping remains about the same even after driving for 20-30 miles.
The tapping seems to be centralized on the engine at the front. There is no difference left to right. Starting from the rear of the engine listening along the valve covers the tapping is most pronounced at the front of the valve covers. Same amount on either side. When I removed the serpentine belt and listened to the front of the engine the tapping was the most pronounced.
My head has me thinking I have two options left. First, remove the cams and replace the lash adjusters in mass. Second, open the timing cover and check for broken sliders. Neither of these are really something I want to do.
If this was an older car with hyd lifters I would put money on a failed lifter. MY problem is, there IS NO DIRECTION on the tapping to even guess which side to tear apart.
I'm really open to suggestions at this point. I've posted on a ford truck forum and had one reply in a week. Hoping someone here has had some experience with this.

 

[TitanMike]

Have you considered taking it to the Dealer for diagnosis?

This may well be a known problem and they might well save you a lot of unnecessary work and parts expense.

 

[Mooney 78865]

Have you considered taking it to the Dealer for diagnosis?

This may well be a known problem and they might well save you a lot of unnecessary work and parts expense.

I have thought of that.
I was out fiddling with it again yesterday. The tapping is definitely coming from the front of the engine. At this point I'm going to remove the timing cover and check it for a stuck/leaking hyd tensioner and what ever else may be amiss. Failing anything wrong there, I'll just replace the lash adjusters and roller rockers.
I have the ability to do the work, certainly have the time. Paying over $200 an hour for someone else to do it is my issue.

 

[realshelby]

While I do my own work for the most part, a $200 service fee to diagnose might be money well spent. I suspect some research on the www might yield some common symptoms and what their cause is. That engine is pretty reliable. It might make that noise for another 100K. But I too would want to confirm what it is.

 

[Sunseeker16]

I seem to remember others having a tapping noise from the engine and it turned out to be the serpentine belt. If I remember correctly, they added an idler pully and that corrected it. There were some threads on the subject some time ago.

 

[Mooney 78865]

I seem to remember others having a tapping noise from the engine and it turned out to be the serpentine belt. If I remember correctly, they added an idler pully and that corrected it. There were some threads on the subject some time ago.

I'd seen that post too. With that thought in mind I removed the serpentine belt and started it up. Noise was still there.
After going out and again going over the engine with a stethoscope the tapping is definitely coming from the front of the engine. I get the loudest tapping response in the center of the block between both banks. At this point I'm going to remove the timing cover and inspect/replace the chain tensioners and related parts.

 

[kenandterry]

Wow. Good luck with your continued search. You’ve already taken more things apart than I can pronounce.

 

[Larry-NC]

Only one belt?

I'd seen that post too. With that thought in mind I removed the serpentine belt and started it up. Noise was still there.
After going out and again going over the engine with a stethoscope the tapping is definitely coming from the front of the engine. I get the loudest tapping response in the center of the block between both banks. At this point I'm going to remove the timing cover and inspect/replace the chain tensioners and related parts.

Is there only one belt? A second belt to an Air Conditioner Compressor or Power Steering pump could be the the source of noise.

 

[kenandterry]

Is there only one belt? A second belt to an Air Conditioner Compressor or Power Steering pump could be the the source of noise.

The Ford Triton V10 has a very long serpentine belt for everything.

 

[TitanMike]

Just a story from my past that was similar.

Friend had a Ford pickup and had a tapping noise similat to what has been described here. He replaced all hydraulic lifters and rocker arms. Not anceasy task on that engine ( a 60's something V-8).

Finally threw up his hands and asked acdealeeship employee. He askedvhim if he checked the eccentric piece bolted to front of camshaft, holding on the timing gear.

Engine was from era when fuel pumps were mechanical and operated on some fashion by the cam.

Friend then pulled the timing cover, replaced the eccentric "cup", bolt, and put back together with new gaskets.

Total cost was less than what he paid for two lifters and took a fraction of the time.

Hopefully the problem will be found before an almost complete rebuild is performed.��

 

[Larry-NC]

My first thought...

Just a story from my past that was similar.

Friend had a Ford pickup and had a tapping noise similat to what has been described here. He replaced all hydraulic lifters and rocker arms. Not anceasy task on that engine ( a 60's something V-8).

Finally threw up his hands and asked acdealeeship employee. He askedvhim if he checked the eccentric piece bolted to front of camshaft, holding on the timing gear.

Engine was from era when fuel pumps were mechanical and operated on some fashion by the cam.

Friend then pulled the timing cover, replaced the eccentric "cup", bolt, and put back together with new gaskets.

Total cost was less than what he paid for two lifters and took a fraction of the time.

Hopefully the problem will be found before an almost complete rebuild is performed.��

My first thought, last night, was mechanical fuel pump. Then I remembered that fuel injection engines use electrical fuel pumps, located inside the tank.

 

[TitanMike]

My first thought, last night, was mechanical fuel pump. Then I remembered that fuel injection engines use electrical fuel pumps, located inside the tank.

Since you mentioned fuel injection, MFI injectors can make noises that sound like valve train noise.

 

[Mooney 78865]

Since you mentioned fuel injection, MFI injectors can make noises that sound like valve train noise.

Checked those as well as the COPs on all cylinders. Nada. I've now been around the engine multiple times with the stethoscope and keep coming back to the front of the engine about midway up. To your point about checking the bolts on the cams, that's on my checklist of things to do. My head is telling me I have an issue with a tension adjuster allowing the cam chain to slap, or possibly having one of the adjusters leaking and not getting good pressure to the adjuster/valve lash adjusters, or finally one of the tensioners. At any rate, pulling the timing cover will be the next step in the process. None of it is hard to do, or expensive. More of a pain in the behind. This coach has been nothing but a joy for the 50,000 miles we've put on it. Maybe I'm due...

 

[Larry-NC]

Another dumb comment.. The Ford Triton V10 has Variable Valve Timing (VVT). Those engines have some slack in the camshaft timing belts/chains. A pair of actuators can take up the slack on one side of the camshaft or the other, thus changing when the valves open/close with respect to piston/crankshaft position.

Poe reports "Fuel injector problems: Ford Triton V10 engines can experience fuel injector issues [2]. Cam phaser wear: The cam phaser, a component of the variable valve timing system, is prone to wear, similar to the related 5.4-liter V8 engine [2]."

 

[MGD1961]

I have some experience with Ford Triton engines in a previous life. I have rebuilt probably 20 or more V10s and many times more V8s. It is not uncommon for the timing chain tensioners to stick and the guides to wear out but they usually will produce more of a clatter than a tick.

If the VVT were the issue it would idle poorly and should set a check engine light.

I would pull the front cover and check the timing components

 

[Mooney 78865]

Another dumb comment.. The Ford Triton V10 has Variable Valve Timing (VVT). Those engines have some slack in the camshaft timing belts/chains. A pair of actuators can take up the slack on one side of the camshaft or the other, thus changing when the valves open/close with respect to piston/crankshaft position.

Poe reports "Fuel injector problems: Ford Triton V10 engines can experience fuel injector issues [2]. Cam phaser wear: The cam phaser, a component of the variable valve timing system, is prone to wear, similar to the related 5.4-liter V8 engine [2]."

The V10 does not have the cam phasers or VVT. It runs a balance shaft on the drivers side head.

 

[ArkRVHog]

Here's a link to a massive thread with a happy ending when my 2018 Ford E450 chassis began a horrible knocking sound (though usually at about 40-55mph) which was solved by adding a belt that Ford had quit putting on our models. Good luck!
https://www.forestriverforums.com/forums/f15/ford-e450-engine-knocking-178880.html

 

[2Ranchers]

We had a 2000 V-10 Triton and at start up there was a small exhaust leak where the manifold met the block. It would quiet down to nothing after the engine heated up. I assume the manifold expanded enough to seal the leak. It sounded just like a mechanical lifter tap.

 

[Joe M.]

I had the same noise on my Ford F150 2009 5.4. It required a new engine. Lucky I had purchased an aftermarket warranty.

 

[JPageMD]

We had a 2000 V-10 Triton and at start up there was a small exhaust leak where the manifold met the block. It would quiet down to nothing after the engine heated up. I assume the manifold expanded enough to seal the leak. It sounded just like a mechanical lifter tap.

X2 for exhaust leak