93 4.0X ATYPICAL valvetrain rattle after repairs

[fatboydan]

I'm sure a thousand people have brought up the subject that every ohv 4.0 owner eventually faces - valvetrain rattle, thinking theirs is unique. I'm not beating them over the head mind you... I'm no stranger to it, but this 'new' problem (maybe problem(s) ) is stumping me.

Facts are as follows:
engine has 112.6K documented miles
previous owner had WAY too heavy of oil in it (20w50 AND lucas additive)
it had badly worn rockers and pushrods when I got it (sounded very much diesel-like and horrible slop in the valvetrain components)
oil pump IS good (+/- 30 psi warm idle)
I ordered brand new hardened pushrods (melling I think, memory fails me sometimes) but I did confirm they're heat treated.
I ordered the "better" rockers on rails with the hardened pushrod seats (term may be incorrect of course)
I have changed both the filter, oil (twice oil, 3x filter) in 1k miles, found no metallic particulates even after inspecting the filter directly, and even the filter mount to a remote mount kit although I find that last bit irrelevant. It is now running the recommended 5w30 oil, with yet another fresh filter as of 2 hours before typing out this post.
The rattle is still there, though not as bad as it once was.
It is verified to be upper end rattle, nothing in the crankcase.
It does not necessarily get louder/deeper/etc when warm, or cold.
Oil is not contaminated that I can tell, with inspection of the oil drained, with limited to no sludge ever coming out of the pan.

My problem is this:
While the rattle is nowhere near as bad as it was, it's still very much there as I said, and the symptoms seem to have reversed in how to reproduce them. Instead of the rattle increasing under load, there is NO rattle under load unless between 2k rpm and 3k.
In fact, there is no rattle PERIOD above or below that number, except at a warm idle where it's consistent... but only on the back passenger side. It is also, when throttle is applied under no load condition, intermittent (although once in a while it stops) within that 2k-3k range.

I have no doubt that there's something I've been missing here. The only components that I feel could cause this which I have NOT replaced are the lifters and the oil pump. I saw no need to change the pump with the pressures being so good. I don't see how the lifters, being rollers, could go bad with so few miles on them unless somewhat plugged up (though it does run VERY smooth) unless running that heavy oil did more damage than good.

But then begs the question, why put the heavy oil in in the first place?

This truck is only a part time driver, so while I don't much care so long as it runs, I know it can and should be better than this. My 91 Explorer has almost if not 3x the miles on the clock and DOES run better than this is right now, with nowhere near the rattle/knock/ this one has, and has never had the valve covers off let alone any valvetrain work done.

Any help, advice or even reference to some sticky/thread here would be great, and I'd be happy to answer any relevant questions about this to help me diagnose as I am able. Thanks!

 

[Rhett]

Is this a manual transmission vehicle?

How many miles on those lifters?

 

[fatboydan]

Is this a manual transmission vehicle?

How many miles on those lifters?

thank you for the reply. Yes, it is a manual transmission vehicle. I believe they are the original lifters, so approximately 112-113k miles

 

[Rhett]

Well, my thought was that it might be clutch chatter / flywheel noise at that specific rpm.

 

[fatboydan]

Well, my thought was that it might be clutch chatter / flywheel noise at that specific rpm.

I wondered about that, as being a relatively new vehicle to my growing fleet of machines I don't trust it yet. Even though with the original chatter/noise I took it on an interstate drive for 250 miles. Other than a noticeable lack of power, it never failed to 'go'. I did the old school stethoscope trick (vacuum tube and even a stick and ear) to just about everything I could reach, and it is definitely isolated to the passenger side upper end. I was enlightened on another site saying one or more of the lifters may be partially plugged or fully plugged. I haven't checked them yet, but I figured if one were bad (since they often DON'T go bad) they all were. Still, it's only that back passenger side area that makes the noise.

 

[Rhett]

How about the cam synchronizer? It's at the rear of the engine, I've had those make noise before. I'm going to assume your 93 Ranger 4.0 OHV has one.

 

[fatboydan]

I'll have to look more deeply into that possibility. Will update when I know more, thanks!

 

[boominXplorer]

I'd pull the lifters apart and clean them. There's a write up on how to take them apart to clean them.

 

[Roadrunner777]

So.... if they put that oil and additive in, who knows what else, right? I'm just throwing this out there, but this sounds a little bit like some kind of restriction in one of the oil galleries... a plug of some kind of congealed crap that is upstream of the oil pump, filter and pressure sensor, preventing the required volume of oil to the lifters.

Also, and I ask this with great hesitation because you clearly know your truck... but if for some reason you missed it somewhere.... just making sure... you know the stock oil pressure gauge is worthless, it's a switch, not an actual indicator. If you are doing all this, I presume you are using a good handheld pressure gauge connected where the oil pressure switch normally mounts.

Yeah, I know, I just have to ask.

 

[fatboydan]

So.... if they put that oil and additive in, who knows what else, right? I'm just throwing this out there, but this sounds a little bit like some kind of restriction in one of the oil galleries... a plug of some kind of congealed crap that is upstream of the oil pump, filter and pressure sensor, preventing the required volume of oil to the lifters.

Also, and I ask this with great hesitation because you clearly know your truck... but if for some reason you missed it somewhere.... just making sure... you know the stock oil pressure gauge is worthless, it's a switch, not an actual indicator. If you are doing all this, I presume you are using a good handheld pressure gauge connected where the oil pressure switch normally mounts.

Yeah, I know, I just have to ask.

A lot of good points - I do know it was driven to where it was parked when I got it and "didn't do that" though I'm 99.999% sure it did have the same problem(s). When I got my hands on it earlier this spring it was more or less the same upper end rattle we all know. It wasn't until I got it up to highway speeds I noticed the rest, and being that I had a 200+ mile trip with a small load in.. I was nervous as he**. But it made it and never got louder, deeper or 'worse'. Fast forward to the first oil change, it came out like water one moment and warm grease the next. Completely flushed (diesel) and refilled. At first I used 10w30, which changed nothing. Now I've got some 5w30 semi-synthetic in there and it seems to be helping, although pressure is down a couple psi. I expected that.

I do realize that about the gauge, err, idiot gauge as I call it. I used a bit of a redneck engineered handheld pressure gauge - mechanical gauge, bit of copper tube with rubber hose at both ends, fitting. Works a treat

That being said, I'm starting to form a theory on all of this based on some new developments. Took it on a roughly 100 mile run day before yesterday. Noticed that now, it's almost perfectly quiet at idle with only the slightest upper end noise. The rattle reappears in the same rpm range as before, yet not as pronounced *until* I let off the throttle. Still, not as pronounced a noise as it was last I was actually trying to notice it. Yesterday I took it for a short spin after warming it up, next to no rattle at all. Rinse, repeat later on, rattle is back. I'm starting to think over my other ideas and am beginning to wonder if there is a partially blocked oil passage or passages that is slowly but surely clearing itself up. I do have some Rislone in it at the moment. I know it's considered snake oil by some and such but it's worked for me in the past. Anyway, my other thought at this point would be to lift the engine up high enough to get the pan clear and see what I can see (again) from underneath.

The last, and least important thing I considered yesterday is that this is NOT in fact a 112/113k engine but more like 213, 313k and the previous owner was either simply full of it, or just didn't know. Hard to tell, but it is what it is. If it frustrates me enough, you all are going to start seeing posts from me in the engine swap sections haha

 

[FR-425]

Mobile 5W30 full synthetic high mileage, which is a high detergent version of the standard stuff.

Full operating temp and run it at 4,000 RPM for ten minutes to clean out the valve train.
Do this under load i.e. while driving in 1st or second gear, don't need a speeding ticket!

DO NOT use any thing other than 5W30 oil or you will starve the crank bearings.

 

[Mbrooks420]

I wouldn’t be taking highway trips in it with additives in the oil. I’d clean the lifters as Boomin suggested, and change the oil to a regular (synthetic) high mileage oil. Have a compression tester?

 

[fatboydan]

I wouldn’t be taking highway trips in it with additives in the oil. I’d clean the lifters as Boomin suggested, and change the oil to a regular (synthetic) high mileage oil. Have a compression tester?

I understand people's concerns with running additives over long distances. However, as I've used this same product in engines repeatedly in the past with great success I trust it. I check the oil daily for extra particulates, metal, etc. So far so good. I'll be switching to full synthetic high mileage anyway once I feel this stuff has done it's job here in a few hundred miles. Thank you for that suggestion

I do have a compression tester, and have already tested the engine. I have not done a leakdown test but did perform a standard compression test and here are my results:

Cylinder
1=165
2=171
3=173
4=167
5=168
6=167

well within ford spec and seemingly in good shape there.

As far as the lifter cleaning is concerned, I'm looking at gasket kits as I type this (multi-tab is wonderful, multi-monitors are where it's at lol)

 

[fatboydan]

Sorry that I've not updated lately - I've been consistently working on the truck with my spare time. I had the heads off and apart, surprisingly things look fine. Lifters were a little gummy but I cleaned them up as best I could and put the engine back together. Still has the rattle, now only when warm. I suspected at that point that I had in fact an oil pressure issue all along, and after installing an aftermarket gauge set (water temp and oil pressure specifically) to monitor everything. Engine doesn't heat up past factory spec (thank the maker) so I know there's not excessive friction... but oil pressure IS low enough to make me nervous. running 5w30 synthetic now after a thorough cleaning of the engine both by flushing and elbow grease... and as the temperature comes up from cold, pressure goes down. just less than 20psi at 2000 rpm warm, under load or not. when cold, pressure is up around 40-45 but doesn't stay there long. based on that, I have to assume the noise left is primarily caused by the low oil pressure.

Have an M328, intermediate shaft, pickup/screen and set of gaskets on the way as I type this. If it continues to rattle after all that, I'm running it till it blows itself apart and then getting another engine. This inherited "free" truck is starting to hurt the pocketbook. May be time for a v8 swap

 

[Roadrunner777]

Your numbers are consistent with my own readings for the last 4 years. I did the oil pressure gauge fix a long time ago and when I first fired it up and got an actual indication on the dashboard, I thought the engine was near its end. But, I still get the same readings year after year... a little higher for a month after an oil change. This vehicle is an enigma to me. My engine and drivetrain show no sign at all of slowing down. But there is now rust damage to the body structure. If this were a unibody, I wouldn't dare drive it, and even so, I'm sorry to say, she could be going to pasture this summer if I find the right replacement.

 

[fatboydan]

Your numbers are consistent with my own readings for the last 4 years. I did the oil pressure gauge fix a long time ago and when I first fired it up and got an actual indication on the dashboard, I thought the engine was near its end. But, I still get the same readings year after year... a little higher for a month after an oil change. This vehicle is an enigma to me. My engine and drivetrain show no sign at all of slowing down. But there is now rust damage to the body structure. If this were a unibody, I wouldn't dare drive it, and even so, I'm sorry to say, she could be going to pasture this summer if I find the right replacement.

Right, they seem pretty normal for any engine with a few miles on it. But after having been on it, in it, driving it, etc for a while the noise directly correlates to oil pressure readings... and I've repaired, cleaned or replaced just about everything else so at this point it can only help by changing the pump and whatnot ... I'm not sure it's worth continually throwing time, effort and parts into it but being more or less willed to me - I want it to run as long as humanly possible so to at least say I tried

I'm not saying I'm 100% confident the hv oil pump is going to be the cure all either - but it has to be of some help and may just be what brings this engine back to 'trustworthy' status for me. The 91, other than a frontend needing bushings soon, is 20x more reliable than I ever thought it would be, just trying to get this to that same point a while