Help required to identify loud raspy noise in 3SFE

[RT104GT]

Hi all.


I have bought a newer 3SFE engine and R/R the old engine in my RAV4.
It took about 7 days and we did the job correctly.
New clutch pressure plate machined flywheel.
Timing belt, pulleys, idler, outside pulleys, water pump spark plugs etc etc.
First of all I replaced the timing belt and water pump as a precaution because my older engine suffered water pump bearing failure at 180000km.
I am experienced at timing belts on various toyota engines and fitted it with correct procedures and it is correctly timed and tensioned.
The replacement engine was started and ran ok warmed up OK and no oil or fluid leaks.

At low revolutions just above idle I noticed a whirring sound which is the same noise that a power steering pump makes when it is almost out of oil.

As the car had just been started I knew there was a fair load on the alternator as well.
So I checked and then I topped up the power steering pump and turned the wheel end to end to get the fluid moving through, the reservoir fluid level went down a little as the air came out but the whirring/raspy noise did not decrease.

2nd test: Remove the alternator belt and start engine again, still same whirring/whining noise low pitched at engine revs.
So I dropped off the power steering belt, they were both new belts correct tension and the right and correct ribs.

3rd test:

Started engine again no accessories are running all belts off
and same noise quite loud coming from under timing belt cover.

Tomorrow I am going to lift off top timing cover belt and observe noise further.
As you rev engine noise increases and then fades a bit as revs go higher.
Engine revs up well into rev range and all 4 cylinders are firing, the engine idles at 500-800 rpm and blows no smoke.

This noise is from the front quite loud and you can hear it inside the car thru the chassis.

The RAV is still on my hoist have not even put the wheels back on.

Q? Would a brand new timing belt, water pump and idler/tensioner pulleys create this noise it sounds like a raspy low pitch siren effect of the teeth running over all the gears?

I have done several belts before including a quad cam 2VZFE and never heard noises like this.

There is nothing loose and nothing dragging.
In a day or two will take off top cover and examine belt and tensioner pulley and take photos if there is some issue.

The engine is full of fresh oil and has been correctly and properly prepped before starting.
The idler and tensioner pulleys were checked and are smooth running wrapped in oil paper.
The water pump likewise is brand new.
The lower crankshaft pulley is tight and the spacer washer was put on in the correct way, curved face out timing gear marks on inside facing the lower crank gear.


How do I know if the vehicle is safe to drive and what could be causing such a loud harsh whirring noise?

Any ideas what noise??

[RT104GT]

I am told by a Toyota tech type that I have the tensioner too tight.
Anyone care to tell me how you measure the correct tension?
What depression should the belt have when pressed by thumb.

[td42gq]

If the belt is in fact to tight then the noise is usually more of a whir type noise rather than a rubbing type sound. If it is a whir just back the tension off a bit and retest. If it is a rubbing type noise than it is more likely that the cover has been bent a little and is touching on the facing of the belt. With timing belt issues you would usually not drive it until it is sorted as they usually cost more money if something else fails. This engine is free running however so engine damage would be unlikely if something fails.

To check tension on timing belts it more of an experience thing than an actual measurement but if you put all the slack to one section of the belt you should be able to twist it 90deg (approx). But as I said it depends on how much force you use to whether this is possible so it's easier just to loosen it off a touch and retest.

I hope that helps
Aaron

[RT104GT]

If the belt is in fact to tight then the noise is usually more of a whir type noise rather than a rubbing type sound. If it is a whir just back the tension off a bit and retest. If it is a rubbing type noise than it is more likely that the cover has been bent a little and is touching on the facing of the belt. With timing belt issues you would usually not drive it until it is sorted as they usually cost more money if something else fails. This engine is free running however so engine damage would be unlikely if something fails.

To check tension on timing belts it more of an experience thing than an actual measurement but if you put all the slack to one section of the belt you should be able to twist it 90deg (approx). But as I said it depends on how much force you use to whether this is possible so it's easier just to loosen it off a touch and retest.

I hope that helps
Aaron

Thanks Aaron yes its a raspy whirring noise especially at 1500 rpm or so.

Just read this........

Timing belts need the least tension of all belts, and are among the most efficient. They can bear up to 200 hp (150 kW) at speeds of 16,000 ft/min.
Timing belts with a helical offset tooth design are available. The helical offset tooth design forms a chevron pattern and causes the teeth to engage progressively. The chevron pattern design is self-aligning. The chevron pattern design does not make the noise that some timing belts make at idiosyncratic speeds,


I guess the comparison with the power steering pump is because with no oil the power steering gears mesh and whirr without lubricant.
And a siren after all is a set of vanes that whirr in the air.