Hi everyone, For some time now I have been working on mechanically restoring my truck.

Along the way my engine has picked up some noises that made me believe the engine had a rod knock and or a timing chain noise.

Keep in mind I am an Ex ASE certified mechanic since 1985 and this truck has me baffled.

I got this truck about two years ago and have been working on it off and on when my pain level allows me to do so. which means I cannot do too much at one time.

anyways I run the truck at least once a week and let it run while keeping an eye on the temperature and oil pressure.

about the last two to three months I noticed what sounded like a rod knock or timing chain noise.

So I have been working on pin pointing the noise.

Things I have noticed the engine is quiet on start up will only make noise once it is completely warmed up.

If I rev the engine from idle to about 1500 rpm you can hear the knock
it goes away after about 1600 rpm.

lately you can hear the noise at idle after I installed a new timing cover fan drive bearing and new drive belt plus serpentine belt tensioner.

I replaced those parts because it seemed like the noise went away once the drive belt was disconnected.

I also felt play and heard a noise while manually spinning these bearings.

the serpentine belt tensioner pulley did not have any play but sounded noisy and the tension spring was weak.

anyways now with these new parts on the engine the engine is super quiet until it gets warmed up then you can still hear the same knocking noise at idle and while revving the engine.

Now while using a long screwdriver to pin point the noise I hear the noise the clearest at the front bearing of the alternator and again the noise goes away when I remove the serpentine belt.

Well I ordered a new Alternator and it will get here next week, I hope this puts and end to the noise yet I have been disappointed a few times already.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

here is a link to a short video I made of the engine noise before any parts were replaced, once I get time I will make another video of what it sounds like now and one hopefully with the engine noise gone.

this first video you can hear a slight knock and some bearing noises, the next video that i have not made the engine should sound noticeably quieter yet i am unsure if you will be able to hear the difference using my iPad as a recorder.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

Have you removed the serpentine and spun the alternator armature by hand? You should be able to feel any roughness in the bearing while it is in place.
Additionally, you can get new bearings and install them into your current alternator. It is not difficult, actually.
It is easy to de-grease the bearings if you cleaned the engine compartment. You would then notice more noise and possible squeaks and chirps. If you do take the alternator apart, you can squeeze grease beneath the seal, and possibly leave the originals in place. But, you want it to be smooth as butter when you get done. Any roughness will amplify over time.
tom

yes I did my best to spin the alternator the fan drive bearing water pump etc.

So far I found the Fan drive bearing to be noisy and I replaced it along with the fan clutch that was worn also, the alternator is slightly rough I have heard worse even the water pump seal sounds dry when spun by hand.

however since I replaced the bearing for the fan drive and belt the loudest noise sounds like it is coming from the alternator.

I may end up replacing the water pump also.

Yesterday while running the engine while it was cold the engine was quiet except for the alternator it had a bit of a whine which got louder and louder as is warmed up then eventually it sounded like a knocking sound.

yes I did wash the engine bay down and the engine but I covered the alternator however It is still possible some cleaner made its way to the bearings in the alternator.

when I get my new alternator I plan on taking the old one apart to see how dry the bearings are.

I purchased a new alternator not a rebuilt one

in the past I have rebuilt alternators yet my new one was cheap enough that is wasn't worth the added work on this truck.

I think the new belt and new belt tensioner has applied more torque to all the pulleys which is why I think the alternator noise is so much louder now.

what is driving me nuts is the sound is very similar to a rod knock

but at this point even if I have a rod knock once I get all the other noises fixed I will have to do something about it

I found a rebuilt engine at Rock Auto for 1750 or so plus a core charge and shipping. if I end up needing it I will just drive the truck until it gets much worse., or sends a rod through the side of the block.

once I get the alternator in and water pump if needed I plan on connecting a oil pressure gauge tot he engine and checking out the pressure.

I noticed my oil pressure immediately goes up instantly to around the half way mark or a little higher while cranking, it happens almost too fast. like someone grounded the circuit with a resistor to fake oil pressure.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

Hi,
The oil pressure "gauge" is really just an idiot light that always stays at half, it never truly measures the amount of oil pressure. You can modify it to make it a real gauge, I've seen threads on forums about how to do that, but it still might not be the most accurate gauge after the mod is done.

My 2003 2.3L has also developed a knock that comes after the truck has fully warmed - it's especially present after driving over 40mph or with the AC cranked up - and it sounds like it could be a spun bearing/rod knock but with my stethoscope, it seems to be loudest right on the the Power Steering Pump & bracket. It's also almost always only present in Drive & Neutral, but goes away in Park. I cannot test the knock by removing the serpentine belt because the knock is so intermittent that if I turn the truck off, get out & remove the belt, then by the time I get the truck started again, it would have gone away anyway due to engine cooling, so it's very hard to know if it's coming from one of those accessories.

Right now, I think my own knock is coming from the P/S pump itself and not a pulley. I found a post on a different forum where the poster had a knock that comes after truck heats up, and he replaced his P/S pump and it was fine after that.

I hope you figure it out. It seems like those accessories on the serpentine belt are often responsible for knocks that scare the daylights out of people by making them think they have a serious engine issue.

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Yeah this noise has driven me nuts, even if I replace the alternator and it doesn't fix the noise that will be one less thing to have to worry about for awhile.

while waiting on the new alternator I drove my truck around the block a few times to try and burn off some of the old fuel, The truck runs great and sounds great from inside the cab even with the windows down.

Today I am going to pull the oil sending unit and just connect a real pressure gauge and test the oil pressure.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

Update
I installed my new alternator now the engine is quieter, however the knocking sound I have been trying to diagnose or repair is still present once the engine is warmed up.

When I spin the old alternator you can clearly hear bad - worn bearings.

The noise I detected at the alternator is gone now that all the other engine noises are gone from the alternator, the fan drive bearing and the serpentine belt tensioner.

Now the knocking sound seems to be loudest at the water pump when accelerating.

this time once the engine was warmed up I had my wife shut the engine off and I quickly removed the serpentine belt and had her start the engine up again the noise went away.

Ford has a TSB about the Harmonic balancer or crankshaft pulley yet under visual inspection I do not see anything wrong with it.

my gut is telling me it may be a timing chain yet I am baffled that the noise goes away when disconnecting the belt.

I am temped to replace the water pump however I am 99 percent sure replacing the pump will do nothing.

the last time I spun the water pump by hand all I could hear is what sounded like a dry seal the bearing felt smooth with no play.

I am tempted to just go ahead and get some help to remove the oil pan and timing cover and inspect the rod and main bearings plus timing chain and gears plus tensioner and guides.

Yet if I do that means at minimum I would need a timing chain set, a harmonic balancer a crankshaft sensor plus the tools to do the work.

this is provided we do not find anything wrong with the rod or main bearings.

I guess this damn truck will not be satisfied until it finishes off my back to the point where even if it is fixed I wont be able to drive it.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

I'm very skeptical about the diagnostic capability of removing the serpentine belt and then starting the engine when you specifically have a knock that comes when the engine is totally hot....because it's impossible to tell if the noise has now stopped because (1) you removed the belt, or because (2) it's simply cooled down sufficiently for the noise to stop.

Hope you get it figured out and that it's not your timing chain. I ordered a salvaged P/S pump that I'm going to install when it comes and hopefully that'll take care of my knock (which is loudest on P/S pump & bracket).

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Yeah I am not sure at this point what the noise is, I know for sure many of the parts I changed needed to be changed the alternator serpentine belt tensioner and fan drive bearing all made noise when spinning them by hand.

as far as shutting the engine off then restarting it and the noise goes away I am just do not know what to say about that.

I even let the engine run almost to the point of overheating and still no noise.

my gut tells me that the noise is the timing chain so I plan on setting the engine to number one top dead center on the compression stroke and then making a timing mark on the harmonic balancer and the timing cover then use a timing light to see if the timing mark moves around while at idle . normally if I remember correctly a worn timing chain the mark will seem like it is floating around and change from advanced to retarded.

Since I posted last I did replace the water pump the engine is now completely quiet until it warms up and will never make any knocking sounds unless I accelerate the engine slightly.

I installed a new condenser, dryer and a few AC hoses plus did a evac and recharge to the ac system so I could run the air .

I have some pretty old fuel in my gas tank that has Stabil in it yet I know it is about two years old.

I have been running the truck as much as I can at Idle with the air on trying to burn this old fuel.

once I get some new fuel in the tank I will get a little more serious about diagnosing this issue.

I have been starting to wonder if the noise I have been chasing is severe spark knock from old fuel. The fuel still smells OK yet after two years I am sure it has overstayed its welcome in my tank.

At this point it does not seem to matter what is wrong with this engine no matter what it takes or how long it takes I have to fix it or pay someone to fix it if I am unable.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

Do you hear the noise continuously with the engine at operating temperature, or, does it just knock a bit when you open the throttle?
I remember some engines that would have a slight pre-ignition knock as you opened the throttle from idle. That was normal and no cause for alarm or pouring $$ bills into new parts under the hood.
Sounds are very difficult to assess from a computer speaker. There's no 'directionality', and what sounds obnoxious from a computer might sound perfectly normal standing alongside the front fender, hood up, engine at idle.
If you ever lay under an engine running at idle, you might wonder how it all stays together given all the noises produced.
OTOH, if you turn up the radio, you might not notice the sound. Sgt Schultz theory of operation as one wag described: "I know nutting."
tom

the noise or I should say noises I have been chasing used to be noticed after the engine was warm under light acceleration from about 1200 rpm to about 2000 rpm

The noise is or was also noticeable at idle once the engine had warmed up enough. Since I have replaced some parts the noise at idle has not returned.

by replacing the parts that had made noise when spinning by hand and also had slop or play in them the engine is now much quieter.

I am sure the engine noise I have been focusing on it not normal and shouldn't be ignored.

one video I made with my iPad resting on the radiator core support you can see vibration that is in tune with the knocking sound.

I will log on with my iPad and post this video.

This vibration which is in time with the noise is what makes me think the noise may be from detonation or a slack in the timing chain.

This process has been painfully slow due to my back and neck limiting what I can do.

However I am positive that eventually I will track down the culprit and fix it somehow.

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Here is the video that shows the vibration I mentioned


Here is the last video I made with the AC now working and water pump replaced along with the other parts I replaced. To me the engine sounds noticeably quieter at idle compared to the first video I posted on this thread.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

I'm thinking like tomw0. Throw some Seafoam in the tank and drive the crap out of it. Looks like you have a nice clean engine compartment. I know small things like this can drive a person bonkers but if there is something wrong, it will rear it's ugly head in due time. I've had people bring me autos to have tune ups and such that make annoying noises like that. I've asked them " how long has it been doing that?", and they say" for as long as I can remember, aint nothing broke yet."

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1995 Ranger XLT 3.0L OBDII
Trans: A4LD (E) 2WD
Rear: 7.5 / 3.45 NL LHD
Tires:GY P235 75/R15 (orig 225 70/R14)
Long Bed, 20 Gal Tank
Up to 229,900 miles

Thanks however since my wife will be driving this truck as much if not more than me I want to know she will not get stranded.

Once I finally run the truck out of fuel I plan on flushing the tank and replacing the fuel pump- sending unit assembly and the filter again.

Then I will add five gallons of fuel and some seafoam I also want to run some seafoam through the intake to try and clean the combustion chamber some.

I still have some fuel system work to do still on this truck it is very hard to fill with fuel I was planning on replacing the canister and vent valve etc under the truck.

The main thing that is keeping me from finishing up this truck is this damn noise.

The only good thing is I am not in a hurry, my wife has a fairly new car and I do not need to go anywhere. It would just be nice to get out of the house if only for a drive.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears

I finally used a second computer that will do youtube. Listened/watched all three productions. The first, boy, I thought there was something bad going on. Every time you'd blip the throttle, I thought something was going to break.
The last, not so much. I would expect some noise, and the little I heard sounded ok to me.
I think I'd take it out for a good run, and when I got back, listen to see if there was any new noises. If you know someone with another 2.3 dohc, ask if they'll start it up and let you listen. I think you'll find your noise production is about normal.
tom

your right the first video sounded bad and the engine was nosier in person.

I believe I have made progress yet something is still not right.

The noise you hear in the last video is only noticed when the engine is at operating temperature and goes away with the serpentine belt disconnected.

I have listened to other 2.3 DOHC ranger engines and probably thousands of engines when I used to work on vehicles for a living.

While I agree this may be normal for a Ranger with a 141000 miles on it. I just simply cannot leave it like this.

I will make another video this time It will be from a cold start to completely warmed up the video should show no rod knock type noise when cold and noisy once warmed up.

While the video is recording I will have the wife shut the engine down I will disconnect the belt and have her start the engine again and we should no longer hear the noise.

If I can catch all of this on the recording it should show that there is something very wrong and needs attention.

one way or the other I will get to the root cause of the issue.

my only hope is someone will have experienced this exact problem on the same engine and found a fix before I end up paying to have a new engine installed.

On you tube I found a ranger making what sounded very similar and he claimed it was a bad timing chain tensioner.

However his noise was worse and loud at idle yet if you listen while he revs the engine you can hear the same rod knock sound I have.

It would have been nice to see a after repair video for comparison.


One thing I will do is record a video and post it after the repair
so there will be clear before and after videos.

the part that has sucked so far is I have found so many things wrong and after each repair I thought this is the part that was clearly bad and should cure the noise. yet it only cured some of the noises that were present.

Perhaps one day I will get lucky and pull the right tooth.

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2002 Ford Ranger 2 Dr Standard cab 2.3 5 SPD 7.5 373 gears