How to: 4.0 OHV Refresh

[410Fortune]

I think it is like 15-20 ft lbs because it’s a steel bolt into aluminum
I have never used a torque wrench on one of those, just “snug it tight” like we have always done with distributor hood down bolts

 

[97Sandbox]

The steel hold-down bolt actually goes into the iron block as far as I can tell.

The spec for the timing cover bolts is 13-15 ft-lb and is also a steel bolt into iron block situation so I ended up going with the low end of that spec, 156 in-lb (my ft-lb torque wrench stops at 20). It felt plenty snug to me. Still seems odd that neither of my service manuals have a spec for that bolt. I imagine it has to be in a Ford manual somewhere though.

This also reminded me of a lesson/warning regarding the timing cover bolts; my manual says 13-15 ft-lbs for "timing cover bolts" and that's fine for the bolts through the front of the cover, but NOT the five bolts that thread into the cover from the bottom. For those, I referenced the oil pan bolt torque spec (much lower). When I started out using the timing cover bolt torque spec, I could feel the aluminum threads in the cover starting to strip before I got to 13 ft-lb. Sometimes I still have to remind myself that whenever something doesn't feel quite right, it's probably wrong (aka stop what you're doing and look for another approach)!

 

[Mordecai]

I should have figured this would get confusing...

Somewhat unsurprisingly, any original paper gaskets and/or phenolic spacer are long gone and a FelPro 90723 was installed under the fuel rail.
View attachment 424997

There are two gaskets (reddish ones below) in the Mahle kit which look like they would have been installed above and below a spacer:
View attachment 424998

I'm guessing it's not a good idea to stack new gaskets on an old one. Would it be better to track down an OEM spacer or just buy a new FelPro gasket? Has anyone had good luck with the FelPro gasket?

I did the upper a few months back with the FelPro gaskets, had decent sized vacuum leak and codes for running lean. So far so good, haven't had any codes since!

 

[Pete Deering]

The

The steel hold-down bolt actually goes into the iron block as far as I can tell.

The spec for the timing cover bolts is 13-15 ft-lb and is also a steel bolt into iron block situation so I ended up going with the low end of that spec, 156 in-lb (my ft-lb torque wrench stops at 20). It felt plenty snug to me. Still seems odd that neither of my service manuals have a spec for that bolt. I imagine it has to be in a Ford manual somewhere though.

This also reminded me of a lesson/warning regarding the timing cover bolts; my manual says 13-15 ft-lbs for "timing cover bolts" and that's fine for the bolts through the front of the cover, but NOT the five bolts that thread into the cover from the bottom. For those, I referenced the oil pan bolt torque spec (much lower). When I started out using the timing cover bolt torque spec, I could feel the aluminum threads in the cover starting to strip before I got to 13 ft-lb. Sometimes I still have to remind myself that whenever something doesn't feel quite right, it's probably wrong (aka stop what you're doing and look for another approach)!

FSM states 15-22 ft-lbs

 

[97Sandbox]

The FSM states 15-22 ft-lbs

Thanks Pete! I'll be sure to torque the bolt a bit more before I reinstall the lower intake manifold and lose easy access. I'll also make a note of that spec in my Haynes manual for future reference!

 

[410Fortune]

You can still access the cam sensor even w upper plenum in place if needed it’s a pita but I have been known to remove the two nuts on the trans mount and jack the t case up until it runs the floor, this gains you some room to work back there just go had forgotten the cam sensor bolt goes into the block!! Too many 5.0s in my life anymore lol

 

[97Sandbox]

That's a great tip! Definitely something I'd rather avoid if possible, but I bet you could even get better access on a RWD truck like mine without a transfer case to be the limiting factor.

 

[97Sandbox]

Finally got everything back together tonight. The truck fired up without hassle, but it has this really bad random metallic popping as it runs at idle. I'm not sure if this is detonation because I've never heard detonation before and the audio in the videos I watched was tough to decipher. To me, the sound is like a rock hitting a sheet of steel and it doesn't seem to happen in any cyclical pattern.

No engine codes have been thrown, but I'm scared to run the truck until I figure out what's going on. If anyone has ideas or troubleshooting suggestions, I'm all ears!

 

[donalds]

Finally got everything back together tonight. The truck fired up without hassle, but it has this really bad random metallic popping as it runs at idle. I'm not sure if this is detonation because I've never heard detonation before and the audio in the videos I watched was tough to decipher. To me, the sound is like a rock hitting a sheet of steel and it doesn't seem to happen in any cyclical pattern.

No engine codes have been thrown, but I'm scared to run the truck until I figure out what's going on. If anyone has ideas or troubleshooting suggestions, I'm all ears!

Post a video please
All around that motor please

 

[410Fortune]

Could it be a lifter pumping up? Does it sound like a pushrod in the valvetrain?

Ohv known for having soft lifters at first cold start the lifter should “pump up” rather quickly and sound dissipate

 

[97Sandbox]

It doesn't sound like a lifter to me, more of a ping than a tap.

Upon first start, I pulled the fuel pump relay and cranked the starter until oil pressure read on the gage in the dash. Then I replaced the relay and turned to the key on position a couple times to let the fuel pump prime and hopefully fill the lines and fuel rail. It started fine, but after maybe 10 seconds I heard the first ping. I let it keep idling for about 5 min, but the ping kept coming and seemed to be increasing in frequency, so I shut it down.

Before taking a video (which I plan to do today), I decided to pull and inspect the plugs. None have any damage (which I would expect from detonation) but the cylinder 5 and 6 plugs had fuel on them and all of them had some carbon chunks stuck to them.

I wouldn't be surprised if I knocked some carbon bits into the combustion chambers when I was cleaning off the heads before reinstalling the lower intake manifold. What's the best way to "clean" that out? Spray Seafoam down the plug holes and let it air dry before reinstalling the plugs?

As for the fuel on the 5 and 6 plugs, I'm really not sure how to interpret.

 

[410Fortune]

Fuel on plugs could mean lack of spark on those cylinders how are the wires?

What is fuel pressure?

Could it be exhaust leak? No loss of oil pressure?

I would clean plugs and not worry about bits of carbon they will drop into crankcase and be picked up by filter or blown out the exhaust

 

[97Sandbox]

Wires are brand new as are the plugs, injectors (technically remanufactured), and fuel filter. I don't currently have a way to measure the fuel pressure unless my scan tool can read it.

I suppose there could be an exhaust leak, but I'm not sure how it would have happened because I never took off the manifolds. Only part I touched was EGR and that was so I could replace the gaskets.

I'm not hearing the type of noise I'd expect from loss of oil pressure.

I'll clean and reinstall the plugs this afternoon and check the resistance of the wires too just to rule them out

 

[fast_dave]

@97Sandbox

Check your compression on 5 & 6.

Positive results will rule out your valvetrain on those two cylinders.

 

[410Fortune]

Fuel pressure you can use a $3 air tire pressure tool for one time use, the fuel will destroy it but it will read pressure for a few
The round dial types work well

 

[97Sandbox]

Compression test results:
Cylinder 3: 165 psi | Cylinder 6: 140 psi
Cylinder 2: 165 psi | Cylinder 5: 160 psi
Cylinder 1: 175 psi | Cylinder 4: 155 psi

Plug wire resistance:
Cylinder 3: 6.84 ohm | Cylinder 6: 11.14 ohm
Cylinder 2: 6.74 ohm | Cylinder 5: 8.00 ohm
Cylinder 1: 7.28 ohm | Cylinder 4: 8.78 ohm

I'll see if I can use a cheap tire pressure gauge to check fuel pressure at idle later today.

 

[97Sandbox]

I reinstalled the plugs and noticed something odd. The 5 and 6 plug wires were not snug on the backs of the plugs and could move on and off easily. Thinking this could have something to do with my issue, I reinstalled my old 5 and 6 plug wires before starting the truck.

When I started it (with plans to check the fuel pressure at the fuel rail), I was hoping the issue would be gone -- it most certainly was not.

I took this video all around the engine.

And this video by the exhaust around the transmission where the noise is loudest.

Unfortunately, I was so focused on the video, I forgot to check the fuel pressure!

Let me know what you all think about the noise in the video, and also about the compression test results. To me, it looks like the right bank is all good as far as compression. On the left bank, cylinder 6 seems suspect, but I'm not sure if that's normal for an engine with 260k miles.

 

[Fix4Dirt]

nearly sounds like my cats, but this one isnt as rapid as mine... mien is same sound, but much more frequent tapping... but yours is similiar locaiton...

 

[EB4X]

LOL! That's the most bizarre vehicle noise I've ever heard...I think there's gremlin that snuck in your engine while you had things apart and he's tapping to let you know he wants out...
Put it in gear and out of gear and see if the sound changes.... wondering if it could be your torque converter...

 

[fast_dave]

@97Sandbox

The video you made helps a lot

I remember this metallic hammering / rock in the can noise - and the first time I heard it, just like you are experiencing, it's a WTF moment!

OK - SO about 10 years ago I heard something similar on a Lincoln Town Car with a Modular V-8.

The people that owned it called me and said "get over here ASAP - it sounds like something's inside the engine trying to get out".

So I went over and investigated - first under the hood.

And like in your case, when I knelt down and stuck my head underneath the car, my ears "told me" that the noise was situated closer to the transmission than to the engine.

So I got the car way up in the air and supported it on 4 jack stands, started it up, and slid underneath.

The noise was clearly emitting from the exhaust system.

Long story short; It turned out that a honeycomb inside of one of the cats broke into a rock size section,
and every time you stepped on the gas the rattling was faster and louder.

Because I was able to order it from a local FORD dealership parts dept. and throw it into the cab of my service truck,
I believe it was one of the small "cold start/quick fire" cats on the Y Pipe that took a dump.

WATCH THE 3 VIDEOS: The thing about this sound being different in each case coincides with which CAT is bad,
and far along it's degraded.

BUT - the one thing that stays the same is that is sounds like it's coming from the inside towards "the out".

Back to your Ex - OK - ANY of your CATS can be bad.

With that said, what I will throw out there is that on the OHV (X-Engine) the Drivers Side Cylinders run hotter because that's the side that the EGR Valve is on.

For proof, the next time you change your valve gaskets' compare the underside of the Drivers Side Valve Cover to the underside of the underside of the passenger side valve cover. The underside of the driver's valve cover will have much more varnish from oil exposed to high temps.

HTH -