I posted this in another thread and got 100 views but have not had a reply so i wanna try one more time but in this thread.

I was able to get a stethoscope, but not really able to pin point the location, It does sound like its coming from the top of the motor more, and i can hear it more towards the back of the engine. Also the noise is more present when i put the stethoscope on the intake manifold. but im not experience and have never had to pin point a noise. i will check again later tonight.



Original post:

First off, I am glad to be a new member here. I hope you guys will be more helpful then the other ford truck forums! So basic info on me, I am 20 and live in San Diego, i just recently bought a 98 f150 a few months ago.

Truck: f150
year: 1998
Miles: 200k
engine: 1997 4.6L V8 Windsor SOHC 100k miles

Now here is the problem, A month or so ago i started hearing this knocking/clicking sound on cold start, it lasted for about 1-3mins. Once the engine has warmed up the sound stopped. Then over time it started to get louder.

I did find a small leak on the EGR tube so i replaced the tube and still have the sound. I replaced the oil with motorcraft 5w30 with a motorcraft 820s filter, the sound is still present. None of the studs are rested on the manifold and still intact. I cleaned the EGR valve, and cleaned the PCV Valve and no luck with that. Does not seem to be a exhaust leak as i used the hose trick and did not hear any leaks.

While replacing the oil i did notice the coolant was low and black, I will be flushing it tomorrow, along with checking spark plugs to make sure there not loose.

As of right now i am lost on what it could be, I read that the windsor engines had problems with piston slap could this be my problem or lifters? What are my next steps to figuring out this problem?

here is video of the noise:
44F9A78B-8CD9-4508-AB74-ADD78801CE62-12734-00000E43D2E36580.mp4 video by peezybro1 - Photobucket

 

From what I could make out it does sound like lifter noise.With an engine around 200k miles you may be at a point of over haul.As time goes the lifter becomes more prone to not retain oil within its self also other ware and tare means they are going to be loose sounding until a renew of parts are done.

 

Thanks for the reply, The engine has about 110k miles on it. It was dropped in to the truck before i bought it. I might be taking it to the dealer soon if i cant figure out the problem.

 

It's near impossible to tell exactly what the noise is from here.
If it is a piston rocking it the bore called piston slap, the only way to tell what cylinder it is is to remove the fuel injector plugs one at a time to see if the noise changes.
This removes the high pressure of combustion in the cylinder and should change the sound.
Oil change usually would have little effect on such a condition.
The slap comes from wear on the piston skirt or cylinder bore allowing the piston to rock in the bore near top dead center.
The noise is usually somewhat a lower hollow sound as opposed to a ticking type.
Rod and main bearing knock sound somewhat the same but more hollow and usually rpm and load sensitive.
As the piston heats up it expands taking up some of the excess clearence so may subsides or goes away.
Another source of noise is the camshaft drive chains.
They are tensioned by oil pressure against the tensioners on each chain.
Depending on how much wear, they may be noisey at cold or hot start idle and go away as the engine rpm rises due to the increases in oil pressure taking up the tension.
A tick often is a valve adjuster and should be picked with your scope when in the local area it is in.
You can use your scope without the needle probe to look for general noise areas just with the handle. It will even pick up air movement noise from the fan.
The noise source locations are subject to the block and heads giving it the sound you hear and water being in the block dampening what you hear.
Exhaust leaks can be dampened depending on how big the leak is or how small and where it is in relation to exhaust pressure to being a ticking sound everytime that cylinder exhausts.
Hope it helps in some way.
Good luck.

 

This helps a lot. Thanks for the detail response. Where would the camshaft drive chains be located on the engine. towards the front and what side? so when i try and listen to the noise i can see if the noise is coming from that general area.

I might give that a try and remove the fuel injectors one by one. Would an exhaust leak be heard clearly on a stethoscope?

What i noticed this morning is that when i started the truck, there was no ticking noise for about 30 seconds then it started, and lasted for about 2-3 mins. it is rpm sensitive (the ticking will be faster) I am hoping its a exhaust leak but its becoming more like a engine problem.

 

You have two cams one for each bank.
They have seperate chains.
Look at the engine's front cover to see how wide it is to house the chains being driven off the crank and the angle involved..
If you hear the noise the way you discribe I doubt it is the cam chain tensioners.

 

Yeah, but wanna make sure for all possible cases. Never can be sure lol. If my friend comes through i will be taking it to ford for them to figure out the problem for free.

Is there anything under the intake manifold that can cause a noise like this? Because in the center of the intake manifold towards the back of the engine is where i heard most of the noise from. I am drawing a blank as whats under the intake manifold.

 

so, after work i listened to the truck and traced the noise to the drivers side cam cover. So i figure it might be lifters? and its loudest towards the back of the engine.

so maybe sticky lifter, low oil pressure at start up?

 

So if i cant take my truck into the dealer for a inspection. i plan on removing the drivers side valve cover and taking a look and seeing whats wrong.

What would i be looking for when im in there, lash adjusters, rocker arms etc. Can i tell if passage ways are clogged? etc. any advice will be nice

 

The hydraulic lash assembly is what your looking at. They are under the cam lobes
Use the scope with probe to hear the sharp tick as oppsed to ohers in that bank.
Should be able to run the motor long enough to find which one but expect some oil to fly around.
Before you take anything apart, go to auto parts store and get a copy of the Haynes 97-03 service manuel and look on pages 2B-9 and 10 at the figures and text for this.
Once you take the cover off, you need new gaskets.
Good luck.

 

So before i take off the valve covers, i started it yesterday morning and the ticking/knocking noise lastes for 5-10mins. and it sounds like it was going in and out, like one second it will be loud, then a few seconds later it would be not as loud but still there.

My friend said i should try Lucas oil stabilizer or something like slick 50? He said that might quiet down the engine. Should i give that a try or should i not run that in my engine?

 

Normally additives are not reccomended.
However sometimes a band aid fix like this might work to satisfy you.
What you need to know is these engines are different than push rod motors in that operating clearences are tight, the camshaft chain tensioners are under oil pressure tension.
If you use a viscosity improver the chains see more tension from higher pressures and permote guide wear especially on a cold starts.
As for Slick 50, I have no faith in the product. Tried it many years ago with no benifit.
Last time I used it was to assemble a single cylinder motor. Found I could not break in the ring seating. Had to pull motor apart and hone the cylinder and use regular oil to get the rings to seat.
I saw all this on my engine dyno.
Sounds like it did something but but never saw a benifit to using it.
For compairison, my 4.6 has 179,000 and has never had anything but Motor Craft 5w20 Blend. Motor is quiet as new.
You make the decision but looks like your trying for perfection on an aged and worn motor.
Sometimes you have to roll with what you have unless it is causing a real issue that has to be taken care of.
My oil pressure is near 75 psi cold start, near 50 psi running normal speeds and 25 psi at hot idle. It has changed very little over the last 150,000 miles.
Good luck.

 

thanks for this, I decided to just to use the Lucas oil stabilizer just to see if it was being cause by something in the valve train etc. I plan on checking to make sure all the spark plugs are tight, and maybe try to unplug the fuel injectors one by one and see if i can pin point the noise to a cylinder or not.

At first i was fine with the noise, but it is starting to get louder and lasting long. At first it was a slight tick/knock for about 1min, now it is lasting on average 4-5mins. It is also starting to make the noise even when just sitting for a hour or two instead of the over night cold start.

I did notice that now when i start my truck cold, the rpm's are running higher. before it idled at around 800 and now is at like 1200.

Also when listing to the noise it sounds like it goes in an out. Where one second it would be loud then another second be quieter but still present.

So i think its time to figure out the problem and fix it as its getting worse. If i have to i will take the valve covers off this weekend and hopefully i find the problem. I don't think its a exhaust leak as the noise is more on top of the engine around the intake. (from listing with a stethosope)

 

Idle is another issue.
Cold starts will get a bit higher and longer as the ambient temps go lower.
As the motor warms the idle should finally drop down to the 650 range +/- 50 rpm.
If it does not, the IAC may be at fault/dirty, the coolant temp not high enough/ thermostat, a faulty temperature sensor, IAT sensor etc.
These directly affect idle, fuel tables and the IAC opening.
Good luck.

 

You said the coolant is black, it is probably an intake manifold or head gasket leak. Look for a intake gasket leak first befor tearing off the head. Water getting into the cylinder under certain circumstances causes a steam knock similar to a rod knock but higher up in the motor. This will lead to furthur damage up to and including hydralic locking and bending of rods/breaking of pistons.