Tapping/Rattle at tickover

[Anonymous]

Hi,
I have a knocking/rattle/tapping at tickover. Only evident when car is warm although I think it is probably only drowned out by the high revs at cold idle hence why I can't hear it.  Noise quickens when throttle lightly pressed (sub 1.5k revs) and clears from then on.  I have an ear for it now, it's coming from the right hand side of the engine -roughly at the accessory belt.  I'm praying it's this, or an alternator.  It sounds a bit like morse code, very subtle and constantly changing pace - i.e. not a steady knock.
Some background, if it's relevant, is that the car ran dry on me about 8 months ago- to the extent that the oil pressure light came on.  From this developed a big-end bearing knock under load.  Replaced bearings and car has ran fine ever since and oil consumption has been fine.  The noise I'm experiencing at the minute has pre-dated the bearing woes and I've covered a good 10K miles since then.  No loss of power noticed nor increase in noise.  Precats exist but are soon to be gutted. Just on a possibly irrelevant sidenote - the battery wouldn't last very long when the car is off - i.e. the sidelights would drain the battery beyond starting in about 45 minutes which initially made me think alternator - the battery had been replaced about a year ago.  Car has 91000 miles.
Any ideas?
Many many thanks

[Dyn-Evo]

Could be the alternator bearings: my old Mk1 had this......?

Also, injectors can make a bit of a racket...?

[Anonymous]

The MR2 has a timing chain instead of a belt on that side of the engine so i'm thinking chain tensioner.

[Jaik]

I've heard the chain tensioner described as sounding like "morse code" when it's on it's way out, so I'd check that.

[spit]

On the 1zz, the belt idler pulley (the big one you can see at the bottom as you look in) has a slack bearing that can lead to an erratic 'morsey' noise. You can rule this out by very carefully applying some downward pressure to the belt tensioner arm at the part that looks like a small shock absorber, while the engine is idling. Use something other than your fingers though!  s:shock: :shock: s:shock:  If you have a fairly long spanner, a better option is to get onto the moulded nut on the arm itself (this is what you grab to release the belt tension) and lever it tighter from there.

Shine a torch on the pulley wheel as you apply pressure and you may see that it stops wobbling. You'll certainly hear a difference if this is the source.

Replacing the tensioner arm can usually help, but its quite a pricey solution that doesn't remove the cause and doesn't always cure. Even a new pulley wheel from MrT has this built-in slack. A new belt may help - easy to fit DIY and only costs 12 quid or so. At your mileage its sensible to do this anyway.

If this isn't the cause and your noise is more rattly than knocky, start looking into things like chain tensioner, particularly if its appearing when your oil pressure is lower as it warms up.

[diddy]

check the cat heat sheild i had to remove mine the other week, had a rattle at 2.5 rev very slight and couldnt find it any were until it gadually got worse like constant and this was the cause even though it looked securley tight a kick to the sheild reveled the rattle i was getting.

[Anonymous]

Had a good root around in the engine bay to try and isolate this noise.  When the engine was off I could feel a little bit of play in the accessory belt, and indeed one of the pulley wheels seems to be the cause.  It sounds like a clink when i move it back and forward, the same noise I hear on tickover.  Can I just buy a new bearing for this? I haven't a clue where to look.  I ordered a new belt for it though so hoping it will at least help matters when I re-tension it.

[spit]

Can I just buy a new bearing for this?

Sadly not. If its the small plastic wheel on the tensioner arm (held in place by a torx bolt), the pulley is actually formed around the bearing so you can't get it out and the part is sold complete with arm so it aint cheap.

If its the big wheel mounted via two adjacent brackets on the engine block, even a new one (at around 35 quid) has lateral play in it so its unlikely to cure things.

We've (me and Custard) have been looking into alternatives/options, but finding the correct spec of bearings has proved difficult. They are very free-running.

[Anonymous]

Oh dear! It really is a horrible noise though, it's hard to believe there isn't a fix for it! Can anyone point me in the right direction re changing the belt? It's all very complicated down there!
Cheers

[Anonymous]

G

[Anonymous]

Can I just buy a new bearing for this?

Sadly not. If its the small plastic wheel on the tensioner arm (held in place by a torx bolt), the pulley is actually formed around the bearing so you can't get it out and the part is sold complete with arm so it aint cheap.

If its the big wheel mounted via two adjacent brackets on the engine block, even a new one (at around 35 quid) has lateral play in it so its unlikely to cure things.

We've (me and Custard) have been looking into alternatives/options, but finding the correct spec of bearings has proved difficult. They are very free-running.

Just to bring back an old issue, I've taken both the tensioner arm off and the larger pully wheel Ste's mentioned above, both have play which I can hear went at idle, I've taken them to a machine shop to have costed made from aluminium plus a strong bearing, which will stop the play which Toyota don't seem to be able to sort out.

I'll post up pic's and a costs for any body interested.

Rob

I would be VERY interested in a costing on this! Also, how did you find access to this area of the engine bay? I can hardly see a thing that I am doing in there!

[spit]

Also, how did you find access to this area of the engine bay? I can hardly see a thing that I am doing in there!

If you know what is where its quite straightforward. If you need a better view, unclip the two hoses on the charcoal canister and lift the canister off its mounting clip. And if you don't want to hack your wrist to bits, remove the mounting bracket too   s:wink: :wink: s:wink:  

Rob - let us know how you get on with the bearings - they're very very free-running and the match that I got from the bearing number on the tensioner pulley was way too stiff to run at speed without getting f-hot.

[Anonymous]

G

[spit]

Seems like your guys know what they're about   s8) s8)  

The pulley with the most play was the the larger idle pulley (Assume this is where AC unit is fitted) it moved about 1- 2 mm side to side  s:scared: :scared: s:scared:

The AC unit is actually nearer the bulkhead and AC-fitted cars run with a longer belt. The large idler pulley is common across the range (unless you're driving a supercharger  s:wink: :wink: s:wink:  ).

I bought a replacement thinking mine was stuffed but they come with that crazy level of play as standard! Perhaps its a MrT compensation for alignment issues with the brackets on the block?

The downside, of course, is that you get the irritating noise as it wibbles. Thats what some members have 'cured' by replacing the tensioner...... but in fact they're only relieving the symptom by applying a little more tension on the belt.

[Anonymous]

G

[nathanMR2]

Looking good mate. Be interesting to see the costs on this

[muffdan]

That does look good. Could be interested myself given a reasonable price.

[Anonymous]

G

[Anonymous]

Just a bit of an update on this - had ordered a new acc.belt which arrived but was the wrong size. (typical!)
I removed the old one, however, to size it up.  I noticed a spell of oil around the tensioner assembly arm, near the spring-like part.  It looks to have lost quite a lot of oil.
I can hear a noise at 2.5-3 k revs now, sometimes and not in every gear.  I'm fairly happy it's not bearings (again) as the noise isn't continuous and depends on gear, also it sounds like it's an issue with an accessory, besides the main engine components itself.
Question is this - a pulley/tensioner that's well on it's way out, would it make noise at other revs? I can hear something slapping about at 70mph on the motorway - can almost feather it.  As I pick up even slightly it all but disappears but when engine braking or maintaining these revs in 5th it's very apparent.

Just praying this isn't big-end.

Thanks and regards

[mrzwei]

Big end is usually a distinct knock when accelerating which increases  with engine revs. Hard to put into words but when you've got it you probably also have oil loss problems and blue smoke from the exhaust. The knock would happen all of the time when accelerating.

[Anonymous]

Hi guys, im a new member with a similar problem to many of you.
I own a 2002 mr2 and have had a tapping sound coming from engine, seems like its coming from the bottom end. I topped it up with oil on tues and still no change. as i was due a service and mot i thought this could possible sort it out. much to my delight (sarcasm) the noise was still there, i arranged for it to be seen by a local garage and all the info i got was its coming from the bottom end of the engine and garages being garages...they advised me 2 purchase a reccondition engine and get them to fit it. Of course i thought i would do my research and found this forum.

After reading several posts i am convinced its the big end bearings as the engine was kinda starved of oil, im trying to locate the bearings but no shops stock them and toyota had informed me they are appox £70-80 but there are 3 types of bearings and the right one cant be determined with out taking them off n having a look. Members that have changed there's, did you have the same problems?

[mrzwei]

The bearings will be specific to the crankshaft and will have a stamp on them to determine the size, usually standard, slightly over or slightly undersize so the garage, or you, shouldn't order the bearings  until you pull the old ones and check. (Same with pistons etc).Most engine builders, eg Rougue, will help you out here, Mr T will prefer to replace the half engine, as you said. If it is the big ends then the crank may also need a regrind so that also needs checking, and, sorry to be doom and gloom, but if the big ends are shot then the condition of the rest of the engine becomes an issue; pistons, rings, valve guides etc. It could be that just new shells will fix it but you need expert advice. Once the sump is dropped and the big ends checked then that is most of the cost, the parts are minimal. A recon half engine from a good engine builder may be a cost option to consider if the bearings and crank are fucked. Advice? Get an opinion from a good engine tech

[Anonymous]

I agree with mrzwei on all of the above.
After some diagnostics it has been determined that once again the bearings have gone for me.  I've caught it early though, which is good news.  It turns out that the belt tensioner has also given up the ghost which is why I was actually hearing 2 noises, one at tickover and one under load.

I paid £38.50 for new bearing shells, not very expensive.  £150 for labour.  It cured it for a year...I blame my own stupidity for the fault recurring - the oil got low a few times and at one stage showed the oil pressure light (a very bad sign as bearing failure will soon follow).  My other mistake was changing the oil- I used 5w30 fully synthetic Motaquip.  Whilst recommended by Toyota, this oil is no longer suitable for my now worn engine, it will take something like 10w40 semi-synthetic to give the correct viscosity for the engine now and will prevent recurring excessive wear of the bearings (take note).

Usually with bearing failure, oil starvation is the cause- but the root will be a leak or some mechanical issue which is bleeding all the oil.  If you don't source this, the problem will likely occur unless you are very very attentive of oil levels.

[Anonymous]

I don't want to create a new thread for this but can someone give me the part number for for the auxiliary belt idler pulley assembly for a 2004,I have searched on here and on toyodiy but cant seem to find it.Thanks in advance.  s:D s:D

[FGrob]

I don't want to create a new thread for this but can someone give me the part number for for the auxiliary belt idler pulley assembly for a 2004,I have searched on here and on toyodiy but cant seem to find it.Thanks in advance.  s:D s:D

Hey Bryan.

Is this what you are after:  m http://www.monkeywrenchracing.com/index.php?cPath=43_91 m
- Price seems OK but you need to add tax & Delivery.

Also from Toyodiy, the listing is as follows:

16620 TENSIONER ASSY, V-RIBBED BELT
16620-22011 1ZZFE..ZZW30 (08/2002 - 11/2004) 1 € 124.02
16620-22012 1ZZFE..ZZW30 (12/2004 - 08/2005) 1 € 124.02

Rob