Timing belt noise after major

So the major is done with new everything including timing chain and oil chain guides and hills tensioners. She runs good but there is a mechanical "whine" noise that is faint and varies with engine rpm. I ran it without alt and ac belts and its the same. If you've spun a dry and worn ball bearing with your hand... that is the noise it sounds like.

My thoughts are that when I set the belt tension I did it wrong. I turned the engine with a breaker bar and had a buddy snug the tension idler while I had forward pressure on the belt. Now its too tight.

I expect now I should have rotated it and let the bar go before snugging. When doing it I noticed it made about 1/4 inch of difference in the placement of the tensioner.

Thoughts on the noise? Belt tension??

2nd. Can I loosen the tensioner and reset tension with engine in?

Any help would be appreciated

 

what car?

 

If 348...

Did you ensure those belt freedom of movement limiter pads at the top of each bank were set with a small (1mm?) gap?

 

91 348. There is a hole in the cover that would allow access to the tensioner bolt. I figure if you take the upper cover caps off and clamp the four gears and belt just for extra security (i cant see how they would move if the tensioner is always "sprung") then loosen and allow adjuster to self tension then retighten it should work?

 

I did set the gap on those pads. They are easy to check so ill pull the cover over gears off today and make sure.

 

The 348 is supposed to have its tensioner bolt tightened at the maximum tensioner load so you could have done it wrong, but it would not be too tight, only too loose. Only 2 possibilities:

1. Bad tensioner bearing
2. Bad water pump

Either way, the engine comes out.

 

Thanks. I really appreciate the help. I'll run some checks today and see what I can find. I have no problems repulling the engine if that is what's needed. The tensioners are new but they could be faulty. Tensioners are hills and felt really tight and smooth when I was fooling with them before installing. I doubt they are the problem. The waterpump never had a noise before the service but could be the problem. I have a feeling it's more to do with something I did wrong.

 

Here is the text from the service manual. Now that I read it again, it does say that tighten the bolt when the tensioner is at its maximum extended position (least load). Which means you could have it too tight. The correct way is for you to turn it over until you observe the position of maximum extension, hold it there, and have your friend tighten the bolt.

It still needs to come out again. And by the way, your reasoning is totally correct. It is something you did (or did not) do.
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Another member here (on a 355) had to change lifters on one cylinder and he did so with the motor in the car by removing the gas tank. Perhaps you can resolve this issue the same way?

BTW, please don't misunderstand this is me endorsing an engine-in-car major, because I do not

 

You (your buddy) shouldn't have pushed the tension idler towards the belt but just let its spring apply pressure. With the tension idler bolt loosened, you should keep slowly turning the crankshaft forward while tightening the idler bolt.

 

I can see it now. Two big guys squeezing into the space meant for one smallish Italian guy, one with a breaker bar and the other with a torque wrench...

Guy 1: Dude, did you shower this morning?
Guy 2: I am holding my breath, why don't you do the same?
Guy 1: Get this done quick!!! I am turning blue!

 

Haha! That's great Mitch. I know I would not fit in there

 

I don't think that is what he is saying. The way I read it he applied torque to the engine and kept the belt taught while the tensioner bolt was tightened. That's pretty much the correct way to do it.

 

To clarify. I turned the crank and allowed the spring to assert its own pressure on belt. All my buddy did was tighten the bolt to lock the tension. He did not apply extra pressure. So given the manual it looks like that was correct. (Rather then turning it and then relaxing the bar used to turn the crank.) which does effect where the idler ends up, and therefore the tension.

So if thats right then I suspect the new tension (old one belt was definately loose/stretched) has brought about a water pump bearing that was on the way out.

 

snug the tension idler = tighten the tensioner bolt, now I understand

 

Depends on who you talk to. They all had springs but yet the factory tells you to use a steager tensiometer and now a sonic testor. I wonder why??

 

What about lower timing case bearings?

 

How I understand the (poorly written) instructions in the workshop manual, the tensiometer is used only to check tension and the tensioning at installation is done using only the spring pressure which should provide 140-160 on the Staeger. Only one re-tensioning is allowed (within first 1500 km) if the tension has dropped below 110. Subsequently, if the tension drops below 110, replace the belt.

 

Never tried it on Ferrari, on our 1, 3 and 4 inch kevlar belts we use these tools to align and set tension or they will snap.
Y'All know how I play with Gates stuff

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Can I borrow your sonic tension meter when I install my cams, Tim?

 

I have to say, the first time I had the belts on my 308 changed I was shocked to see how loose one belt was. And I mean LOOSE! With the engine off there was absolutely no tension what so ever on the drive side of the belt. It was like a fat man's belt around a skinny man's waste. Note, first time belt change. I.E., that's how it came from the factory. They obviously didn't spend much time checking belt tension back in '85. And, no, this was not due to belt stretch. I measured the length of both old belts. One was 915.4 mm and the other was 915.2 mm. Basically within the manufactured tolerances for belt length.

 

So.... i pulled the engine again and changed the case bearing and the ball bearing ng at the back of the timing drive. Timed the cams when I was in there. Changed water pump and installed a new belt just in case. Put it back together and quess what? Still have the bearing noise. Hills tensioners felt good when i was checking. What else is there? Noise is definitely coming from front of engine and started right after last year's major. I drove it all last year and noise didnt get better or worse. It sounds like a quieter old school gear drive.

 

Idler pulley bearing for the accessory belts?

 

I dont know Dave kinda sounds like you do.

A bit at least, ha ha.

 

That is the water pump and one of the two Hill Bearing. I think he said it is done.

As for what to do now, I would take a stethoscope and poke around while the engine is running. ...