Engine rattle investigation (2 Viewers)

[clx16]

So I have had a rattle that used to go a way after a few minutes. Then it got to the point that it was getting louder and not going away. Previous recordings made it hard to hear it over the sewing machine sounds but finally got a good recording.



Could never hear it with a engine stethoscope, no matter how many places on the block and assesories.

Changed out the timing chain tensioner, ran the bore scope in every direction thinking I had a broken chain guide and everyone looked fine but the sound didn't go away. Went up to a thicker oil and still nothing changed.

Pulled the valve cover and checked that all the cam bolts were down as well as checked the valve spacing to the cam shaft lobes and they were all in spec. So decided maybe it is my Chinese distributor, so I pulled it and it had no play or rattle to it. I still rebuilt an oem one and put that in. I Thought maybe the belts were making noise because they had once gotten antifreeze on them, So decided I should also change out the harmonic balancer while I was at it. I also wanted to see why I still have a small oil leak up front so figured I would try to check the oil pump housing and change the front crank seal also. So I did and put in new belts...

While I was in there I checked all the pullies for play and rolling noise....nada.

But I did find this


The splines do not look to be wearing evenly and so I figured I would replace the oil pump with a new one.

Started her up today and no more rattle.

 

[ceylonfj40nut]

Bingo. Was going to suggest that!

 

[clx16]

Bingo. Was going to suggest that!

Really wish someone would have, I have been not driving this thing, thinking it would grenade at any moment over a 15 dollar part. Lemme say I am pretty happy that it's gone!

Timing now is at 3 degrees but I am all the way to the full clockwise position so tomorrow I will move it a tooth and then I can set it back to 5 or 6 degrees like I like it.

 

[ceylonfj40nut]

Many nick the power steering pump gear wheel when removing it, not the part you are referring to, but both make noise. I have to do this but been placing it on the back burner

 

[80t0ylc]

Familiar noise on my ‘94, mainly when cold. Curious, How urgent is this to fix? Just under 300K on the clock, so want to combine some engine projects for minimum down time.

 

[ceylonfj40nut]

Not super critical. Can be done with other planned repairs.

 

[Kernal]

"Could never hear it with an engine stethoscope"

Edited because I missed the post where replacing the oil pump rotor fixed the rattle. Good job.

Seems like that's the first time on the forum that anyone has reported a rattle from worn oil pump rotor shaft splines??

 

[clx16]

The recording I have was a very good recording of the sound. I agree that it is usually very different so I was moving the phone around during the recording to make sure it wasn't all fan or air noise etc. And for the record one should pull the belts and run it before pulling intake manifold and valve cover off etc.. one of those times I felt like I skipped obvious diagnosis steps.

In my case I checked fan clutch, water pump, alternator, ac compressor and tensioner and couldn't find anything making even the slightest rattle. Which is what I was double checking when I had the belts off. While had the intake manifold off I was putting a camera in to see if something was bouncing around on top of the valves. Buddy of mine said the same thing about it sounding external and to try running it without the belts but I was already with the valvcover and intake off as well as harmonic balancer so starting it up was going to have to wait till I got it back together. I just figured I would see if my oil leak was from a groved harmonic balancer and happen to pull the oil pump cover to check if the leak was something I messed up with the oring I replaced previously.

Last year, I rebuilt the power steering pump and made sure to file any dents from the gear created from handling and pulling by a previous owner. I had hoped that was going to fix the rattle back then. Although new doesn't mean good, a lot of the bearings (alternator, ac tensioner, water pump, and clutch fan) were all very young and Japanese. The replacement harmonic balancer was purchased a few years back while I was trying to find the noise thinking maybe mine was separating and making that noise. Now that I have the old one off, it seems to be in good shape so holding on to it as a spare now.

The rattle had gotten so bad that I could hear it while idling with my windows down so I am very excited that the rattle was gone this time.

Another thing to note.. the rattle, to my ear sounded like it was coming from the front of the valve cover. I hope this helps people track theirs down.

 

[CrabCake]

Thanks for posting this and also with your findings and repair. I don't have this problem with mine, but I always like to read through threads like yours so I'm better informed if/when I have an issue in the future as mine ages. That's what these forums are all about....

 

[mdawg]

Amazing, this is GOLD. Thank you for posting this @clx16. I was investigating this exact same noise yesterday morning; that kind of irregular, clackety rattle when the engine was cold. Using my stethoscope I was hearing the noise loudest on the timing cover just above the timing marks; I'm sure if moved a little to the right (at the top of the oil pump cover) it would be even louder. You've saved me a lot of time here. Thank you!

 

[clx16]

Remove the dampener. 14mm on the flywheel bolt. Lay on your side with feet on the passenger side tire and the big 3/4 ratchet and make sure nothing is next to you head when the bolt comes loose! Also take the fan clutch and strap it up and over in the shroud carefully.... pulllllll! The rest is easy.

 

[clx16]

Amazing, this is GOLD. Thank you for posting this @clx16. I was investigating this exact same noise yesterday morning; that kind of irregular, clackety rattle when the engine was cold. Using my stethoscope I was hearing the noise loudest on the timing cover just above the timing marks; I'm sure if moved a little to the right (at the top of the oil pump cover) it would be even louder. You've saved me a lot of time here. Thank you!

I am sure it isn't good for the bushing in the timing cover or the oil pump cover so Don't wait too long or you might have to pull the head and oil pans to fix it later. If you order from partsouq it's 15 dollars or so and 12 dollars shipping. That shipping stays the same until you go nuts so add in a crank seal and oring for oil pump housing and a few spare nuts and bolts you may want to have handy.

The job is easier for me than most as I ditched the screws in the oil pump cover and went to hex a long time ago. Either way it's time and not expensive yet.

 

[Malleus]

Someone did me the same favor; replaced every one of my pump covers screws with SCHS, which they also Loctited in place. Moron.

I don't mind the SHCS; but they're too small to torque with a tiny hex wrench to break the Locitite.

 

[clx16]

No lock tight on mine and they were still very snug so there is no need for this application ha. But hey if one nail is enough 100 has to be more better.

Actually bad memory theg are m6 x 12 TORX

 

[mudgudgeon]

No lock tight on mine and they were still very snug so there is no need for this application ha. But hey if one nail is enough 100 has to be more better.

Actually bad memory theg are m6 x 12 TORX

I think I'd prefer the original JIS screws over a hex/torx so small.

So far I've had no trouble with these using the correct fitting bit in a cordles impact driver. (Good control and strong torque)
Maybe fortunate no PO has boogered them first

 

[clx16]

I think I'd prefer the original JIS screws over a hex/torx so small.

So far I've had no trouble with these using the correct fitting bit in a cordles impact driver. (Good control and strong torque)
Maybe fortunate no PO has boogered them first

Well the benefit of the torx is that I was able to get them loose without even removing the fan shroud, didn't even need room for my Dewalt dcf850, just a ratchet. I did have to use a pick to clean 3 of them out first though.

 

[clx16]

Adding some addition pics. There is not much rollover on the top edge. It does not feel like it it very worn but it certainly was enough.

 

[fjbj40]

I used locktite on my oil cover screws.

The purple stuff, for small fasteners. It’s a great anti-seize and 1-2 ft/lbs breaks it loose.

But this thread is gold! Probably going to help plenty of people

 

[mudgudgeon]

Adding some addition pics. There is not much rollover on the top edge. It does not feel like it it very warn but it certainly was enough.

View attachment 3353139

View attachment 3353141

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View attachment 3353145

Looks kinda second hand, and mildly beaten up?
Wonder if it's slightly bent?

 

[clx16]

I don't have any documentation to say it was replaced by the previous owner so it is my assumption it is the original. There were lots of records that came with the vehicle but it seems like it has very little issues. there was a wheel bearing replaced, windshield and looks like the guy was honest about it having the headgasket done based on the evidence of the head being cleaned at some point and still being very clean.

It is possible they did pull the timing cover etc, I just don't know.

I should have inspected the inner splines of the gear while i had it apart, if I were to do a timing chain job, i would just replace that gear and do the oil pump rotor too while i was at it.