Hi Guys! I'm new to this site. I just rebuilt the 4.0 sohc in my 2001 ranger 4x4. This is one crazy motor to be rebuilding. Most everything has been replaced. On the initial start up, everything seemed fine. But after a few 100 miles, I started to hear some ratting noise. I traced it back to the right rear. I can hear it rattling at the oil pan girdle and transmission bell housing. I searched the internet and only came across one video where the poster possibly had the same issue I'm having. Unfortunately there was never a resolution posted. I thought it may be the hydraulic tensioner. It was new from the cloyes timing kit. I switched it out with a new motorcraft hydraulic tensioner. I primed it with oil, but the noise is still there. I even grabbed a couple of junkyard hydraulic tensioners to test. Same results. The rear chain is higher than where the noise is coming from and I can't hear the noise from the right valve cover.
Would the torque converter be making rattling noise? Any help is appreciated.

 

Does it make the sound when the truck is sitting still. If so does it change when you rev the engine? Does it do it or change sounds if you sit still with the brake on and move the shifter through park. neutral and drive?

 

I'll have to try that. I know the noise is there at idle cold or hot. I recall reving it but couldn't really hear the noise because of the engine rev. I'll listen closer. I'll try shifting when on the brakes. Actually I'll get someone to do that while I listen from the right wheel well.

 

I used a stethoscope to locate the noise. Initially, when I started the engine, I did not hear the noise. As the engine warmed up, the rattling/tapping noise started. I can hear that rattling/tapping noise more from the bell housing. I hear it at the lower right side of the girdle as well, but not as loud as from the bell housing. I placed the stethoscope around the other side of the bell housing near the starter and still hear the noise. I couldn't really detect the noise from the top of engine by listening at the valve covers. With the engine revving at 2000 rpm, the noise is drowned out by the fan, motor etc. but I can still hear it with the stethoscope. The rattling/tapping seems to keep up with the RPMs.
With the brake on and shifting though the gears, it didn't seem to change the noise.
I'll wait until the engine is cold and I'll try it again.

 

If you slip the belt off the fan it may make things easier to hear, just don't let it run for more then 1 minute because you will have no water pump.

 

I'll try that. At least there is no squeaking from the idler or tensioner pulleys. I installed new ones after I rebuilt the engine. The engine ran smooth, but it had those annoying squeaks from the pulleys.

 

I removed the serpentine belt and started the engine cold. No rattling noise until the engine warmed up. I would describe the noise to be similar to a paint can. As the engine warmed up the noise reached a certain volume and maintained that volume. As I rev the motor to 2000 rpm, the noise did not get louder, but the noise was faster. Changing gears at idle made no difference, it seemed to pause a quick second as the gears shifted. The noise is heard loudest around the bell housing. I listened to the catalytic converters and the noise is definitely not coming from those.

 

Pull out starter motor, see if starter gear is loose and hitting ring gear

 

The noise starts after the engine warms up. I would imagine if the starter is the issue, then wouldn't that noise happen at the get go?

 

Did you change the oil pump?

 

Yes. Most everything was changed when I rebuilt that motor. I could not risk keeping an old "heart". I used a melling pump with the melling pick up tube. I didn't like the plastic pick up tube. I placed the stethoscope around the oil filter housing and oil pan to see if that noise was in that area. It's loudest at the bell housing.

 

Can you grab the crankshaft pulley and move it front to back when the belt is off and NOT running? Can you pull the spark plugs and rotate the motor by hand to see if you can hear anything suspicious?

 

I recall checking the thrust clearances with the machinist. It was very very slight movement.

 

When mating the trans back to the engine, were all the alignment dowels present for proper fitment? Did it go together easy or did you have to draw it together with the bolts?

 

You have a point there. The dowels on the block were not an issue. I made sure the torque converter seated. I spun the converter around a bit before it seated in kind of like two steps is how I would describe that. What was a challenge was trying to get the correct angle and clocking of the block and bell housing. When there was about an inch gap between the bell housing and the block I wasn't able to get any closer but everything was lined up. I pushed on the block a few times when I realized the studs on the converter needed to slip through the holes of the flex plate. I guess I was tired and my mind wasn't clear. I had painted the ends of the studs so I could see them easier through the starter opening and I entirely forgot about that. So I turned the crank until the studs aligned and went through the flywheel.

I originally had to rebuild the motor because it toasted after all the coolant leaked out. I dropped the tranny pan to change the filter and fluid because I was a bit concerned if the excessive heat may have affected the tranny. I did notice the pan had a lot of fine gray metal. It was mostly around the magnet. It was more of a gray residue. No big chunks. So I thought that the residue was normal wear.
So maybe I did damage the torque converter. I hear that rattle noise a few minutes after I start the engine and it warms up.
Does a torque converter actually make a rattling noise when damaged?
I've heard bad transmissions when they have that whining noise. Sounds like a bad power steering pump.

 

I got an oil restrictor from a 05 4.0 SOHC. The 05 intake was a nice design. It allowed easy access to the oil galley plug, It's also easy to get to the left side hydraulic tensioner and t-stat housing. Unfortunately, in order to get to the oil galley plug on my 01, I had to remove the intake manifold. I installed the oil restrictor hoping that it may build pressure in the right side hydraulic tensioner. It made no difference. The engine is smooth and quiet at cold start. Once the engine warms up the rattle gradually starts. The noise is heard loudest at the bell housing, I'll do some research on torque converters,

 

I, myself haven't experienced a torque converter that rattled when it failed. I have encountered quite a few cracked flex plates through the years though. Some sounded like a rod knock, some like a handful of bolts in a blender, some like a loud lifter tap. So when I hear noise coming from around the bellhousing on an automatic, that's the first thing I want to investigate. Now the temperature thing you mention kind of throws that theory off, but I can't completely rule it out. Metal expands when it gets warm, so that can change the dynamics, as in small cracks can get bigger etc..

 

I will be pulling the transmission and see what I find. I did not notice any cracks on the flexplate when I installed it. I would imagine any cracks would be at the bolt holes.

 

Yes, In my experience, they have been where the plate bolts to the crank. I did have one that just had the holes wallowed out from having loose bolts.