Just got my new built engine started, what is this noise?

[90T04]

I just got my freshly built engine started up for the first time. It started right up on the first crank, no leaks, purred like a kitten. Then right before I was about to go break it in I start hearing this noise, sounds like something squeaking in the engine. So I figure its an accessory or a belt. Removed both belts and re-start. Its still there.

It sounds louder from the bottom of the engine, and it goes away if I crack the throttle at all. Its only audible at idle. I pulled the injectors one at a time and none of them make a difference. Oil pressure is about 35psi at idle with a brand new shimmed toyota oil pump.

This motor has probe pistons, eagle rods, and clevite bearings. All clearances were plastigaged dead on, everything turned over beautifully on the engine stand, etc. I am not saying Its not possible I screwed something up, but this is just a weird sound. Its not my exhaust rubbing on something, I checked that.

Here is a video I took.

http://www.youtube.com/watch?v=OBANeo0CkBE


Does that noise ring a bell for anyone? Someone tell me its just a new engine sound, and it will go away:icon_sad: Should I just take it for a break in drive, and see if it stops?

 

[lewis15498]

Did you replace the timing belt tensioner?

 

[IJ.]

Pop a cam cover and make sure it's oiling up top.

 

[90T04]

Did you replace the timing belt tensioner?

Yes, brand new toyota one with a new spring. Also a new toyota belt. Oil pump drive shaft bearings were replaced and clearanced properly too. Sometimes forged pistons will slap when cold, but that wouldnt sound like that would it?

 

[90T04]

Pop a cam cover and make sure it's oiling up top.

I can see plenty oil in under the oil cap but ill take them off and have a look anyway.

 

[IJ.]

What were the thrust bearing clearances?

Auto or manual?

 

[90T04]

Just looked at the cams, everything looks oily and like it should.


I have in my notes that my thrust clearance with new bearings was .0040. .0020 to .0098 is spec

manual

 

[IJ.]

Run it and try pushing the clutch and see if the noise changes.

 

[90T04]

Run it and try pushing the clutch and see if the noise changes.

Wow, when I depressed the clutch the noise went away. When I let it out, It was gone. I let it run for a couple more minutes and gave it a couple of small revs and it did not come back. The only other thing, is that It has been about an hour and a half since I last ran it, so maybe it is slightly cooler now.

I am more confused than before.... maybe it was a clutch alignment problem or something???

 

[IJ.]

LOL I'm magic

 

[90T04]

LOL I'm magic

Youre the man IJ,

Well im going to go break this sucker in now, wish me luck!

 

[IJ.]

<fingers crossed>

If it shows ANY signs of distress STOP.

 

[grimreaper]

^ was that lack of oil on the thrust bearings(or thrust bearing that was being pushed on by the PP)? spill the beans merlin..

 

[3.0 GT]

^ was that lack of oil on the thrust bearings(or thrust bearing that was being pushed on by the PP)? spill the beans merlin..

sounds like most manual transmissions...

 

[90T04]

Well I went for a 20 mile drive closely following the break in procedure and the engine felt really strong, sounded good and didn't give a hint of trouble. I stopped halfway through and just listened for any unusual noise. Didn't hear anything weird.

When I got home I pulled into my garage, and unmistakeably there the noise was again. So I depressed and released the clutch and it went away.

If it were a loose thrust clearance it would have to be way loose to cause that noise. Also wouldn't the RPM's drop when the clutch pedal was depressed? The RPM stays steady. If the clearance were too tight, I am not sure what the result of that may be.

I am hesitant to just live with the noise, but I really dont want to drop the pan just to investigate.