Whining noise after engine rebuild

Schwamm

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2003 Mazdaspeed Protege, 2008 Mazda 3 Hatchback, 1984 RX7 GSL-SE
I just got my car running again after a rebuild. It runs great, just like it used to, except for a strange whining noise near the left side of the engine (belts area). I can hear it over the engine noise when driving, and it becomes more high pitched at higher RPMs. I took each accessory belt off individually and still heard the noise, so it's not my alternator, AC, power steering, or the water pump. I also re-tensioned the timing belt to make sure it wasn't too tight, and checked to make sure the pulleys were spinning as expected. When poke around with a screwdriver and listen for the noise, it's loudest on the water pump but I can't reach much else in that area.

I replaced the timing covers, and the oil pump, but not the timing belt or pulleys because they were replaced not too long ago.

Any ideas what this noise could be or what I could check next?

 
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Looks like it's the timing belt tensioner. I put my old one back on and the noise went away. Somehow it got messed up during the rebuild and was vibrating against the timing belt when it spun
 
It actually wasn't the tensioner. The noise was just quieter when the belt was looser. I still can't solve this and so far I've tried:

1. Running the car without accessory belts (a/c, water pump, etc.)
2. Swapping out the tensioner and idler for an old set
3. Buying a new tensioner
4. Replacing the timing belt
5. Re-installing the cams to make sure everything is lubricated and torqued correctly

I've spent nearly a month trying to find the source of this sound. The only new part that's moving and hasn't been swapped out is the oil pump. Can those make noise when they're brand new or using non-detergent oil?
 
It sounds like a belt rubbing to me, not a bad bearing sound like an oil pump would make. Do the timing covers have marks on them from the belt hitting them?
 
I agree that is sounds like rubbing, but there isn't an obvious place where it's rubbing that I can see, nor is the belt damaged. I have been running it with the timing covers off for now. I'm tempted to just order all new OEM timing components today...
 
Does it make the noise without the covers installed? The belt won't really show wear but the covers will, when it happened on my old motor the tensioner and spring were worn out. Replaced them with the belt and it hasn't had any problems.
 
Yes the covers have been off while I'm doing this testing. The valve cover and crank pulley are the only things on. I do see a little black residue on the tensioner and idler on occasion, even though the belt is brand new. Not sure if the noise could be coming from the belt making contact with either of these. I can't pinpoint the source of the noise because sometimes it sounds like it's up top by the cams, and sometimes by the idler. It's as if the whole belt makes noise. The old belt did it too though
 
The noise still happens without the water pump turning? Is it hitting the valve cover? I don't know what else it could be. I don't think it's the oil pump but it could be. It's hard to diagnose online, sorry I can't be of much help.
 
Any ideas are helpful. I know a video only does so much.

Yes, it happens without the water pump. Since the noise changes with the tension on the belt I also think I can rule out the oil pump. The only things turning are the cams, crank, oil pump, and timing components. I had not considered that it could be hitting the valve cover but I will see what I can find.

For my own sanity, what is the order of components on the crank? I currently have the timing belt gear on first, flange against the oil pump, then the washer with the curved part facing out, then the crank pulley itself. Anything wrong there?
 
For my own sanity, what is the order of components on the crank? I currently have the timing belt gear on first, flange against the oil pump, then the washer with the curved part facing out, then the crank pulley itself. Anything wrong there?

No, that's correct.

Did you mark the main caps before you removed them? Both the location and orientation?
 
Random question. Could cam seals cause this? When I first installed them I didn't oil them well. I re-installed the cams and oiled them the second time around, but the seals themselves had wear marks on either side, 180 apart where the cap meets the head. Do these spin with the cam, and can they cause noise?
 
The seals stay fixed, the cans spin inside them. I don't think they would cause the noise, but you can try lubricating them.
 
So I noticed a tiny oil leak from one cam seal, and combined with the wear I saw on them I'm thinking maybe the caps behind the cam gears are not fully seated. I did use RTV and torqued the bolts to 8ftlbs so it's possible I used too much RTV and those end caps aren't flush, which would allow the cams to move up and down with the tension of the belt. I picked up new cam seals today so I am going to try carefully redoing those end caps and see what happens
 
I redid the end caps on the cams last night and didn't see a change. I noticed my timing belt has a significant amount of side-to-side wobble. You can see it plainly even at idle when the covers are off. Is this normal? Is it possible to stretch the belt too much when installing it? I installed it by getting it on the crank, around the idler, and then the cams, and then twisting the tensioner out of the way as much as I can and forcing the belt around it
 
That's how I install them. You replaced the tensioner spring? The belt should not move on the gears, it should be taut enough that it stays in one place.
 
Last night I dug up my old, original timing belt with 140k miles on it and installed it with the old tensioner and idler, and for the first time the noise went away. I also noticed that the tensioner was able to pivot easily even when tightened down, so the tensioner spring was really doing its job. With the other tensioners I have, it took some force to pivot the tensioner with the allen wrench when tight, so I think the two Continental belts I had were run too tight and ruined, because they had a lot of wobble to them even with the original tensioner after that. I think the root of the problem was bad tensioners, but it could possibly have something to do with the Continental belts too.

I ordered all new OEM timing components, so hopefully I'll be good to go as soon as those are installed. Thanks for all the help here
 
Last night I dug up my old, original timing belt with 140k miles on it and installed it with the old tensioner and idler, and for the first time the noise went away. I also noticed that the tensioner was able to pivot easily even when tightened down, so the tensioner spring was really doing its job. With the other tensioners I have, it took some force to pivot the tensioner with the allen wrench when tight, so I think the two Continental belts I had were run too tight and ruined, because they had a lot of wobble to them even with the original tensioner after that. I think the root of the problem was bad tensioners, but it could possibly have something to do with the Continental belts too.

I ordered all new OEM timing components, so hopefully I'll be good to go as soon as those are installed. Thanks for all the help here
Glad you got it fix, Austin!
 
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