TD5 engine noise

[TroyMortimer]

hey guys, I only seem to be posting under negative circumstances....

really need some help with diagnosis on this sound.

made a clip when hot and cold.

you can hear the sound from all different positions around the car

I'm really nervous this is something serious, my first thoughts were big end bearings, praying it's not.

TD5 noise. What is it? - YouTube (https://youtu.be/NUuO6AszLy0)

[johnp38]

First up just pull the cover off and check that one or more of the injector rocker arms haven't gone out of adjustment.

Only saying coz it sounds up top (ish) and easy check.

The sharper noise is also more indicative of piston slap rather than bearings if you were suspecting a block issue, also whenever a crank or big end bearing starts going it goes quick and gets very loud.

Having said that I stripped down a reco motor to find a big end half shell completely missing ?? and it had been driven for weeks since installation with the simple fix being a new set of bearings and no crank machining and it went for years after that.

Don't guess just open the cover and eyeball and if nothing is broken/loose up top at least you have started the process of elimination.

Get a big screwdriver and do the old timers trick of listening through that.

It's all best effort guess work getting advice on a forum.

[TroyMortimer]

will do. really appreciate your suggestion

[V8Ian]

Recorded sound always loses something in the translation. Automatic? Could be flex plate. Also check the harmonic balancer.

[TroyMortimer]

yep automatic. for the harmonic balancer just check for play? I presume without the belt on and see if the noise disappears

[TroyMortimer]

nuts are solid. injector harness was really oily. I swapped it over with one I had in parts draw. however there were no error codes on the nanocom.

I noticed that not a huge amount of oil was on the rocker / cam.

here is a little clip

TD5 rocker cover off - YouTube (https://youtu.be/ogYFY00Qmwo)

when under the car. it sounded like it was the exhuast. I'm going to try the screw driver next.

[johnp38]

I noticed that not a huge amount of oil was on the rocker / cam

That's fine, mine were the same with a thin coating of oil(but black and filthy rockers and cam carrier, not sparkling clean like yours) the oil sitting in the pockets next to the head bolts is the excess flying around, so you are oiling up ok.

The inspection plate on the bottom of the bellhousing comes off easy and you can spin the motor with a screwdriver in the teeth (not much effort required, on mine anyway) and you can shine a light in and see the flex plate to check for cracks.

Also just an afterthought did you push the little inlet/exhaust valve rocker arms sideways to make sure all the lifters were pumped up and holding rocker arm up against cam. you could have a collapsed lifter that may not be obvious with the valvetrain sitting under the cam

So I hope you haven't put cover back on yet !

I have had power steering pumps, aircon compressors and even the bloody accessory drive belt make similar slapping noises and have me chasing my tail.

It is a process of check and eliminate.

[TroyMortimer]

Also just an afterthought did you push the little inlet/exhaust valve rocker arms sideways to make sure all the lifters were pumped up and holding rocker arm up against cam. you could have a collapsed lifter that may not be obvious with the valvetrain sitting under the cam

.

what you mean push the little exhaust valve rocker arms sideways?

the rocker cover is sitting on top, but not screwed down.

[johnp38]

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You have the cam carrier on top so need a longer screwdriver

the lifters should hold their oil pressure with engine off (take a long time to bleed down under pressure) so by giving a push sideways on the rocker arm it should be firm, if you have a buggered lifter the rocker arm will be loose/sloppy and even though the lifter will/may pump up when the engine is running it may still cause that noise by not being able to take up the clearance under running conditions.

This is just speculation, as said before it is just guesswork of possible causes, but also a valid test as part of the process of elimination.

You are the man in the arena the rest of us are just well meaning spectators with suggestions.

No more pics too cold out there.

[TroyMortimer]

171700171701171702

You have the cam carrier on top so need a longer screwdriver

the lifters should hold their oil pressure with engine off (take a long time to bleed down under pressure) so by giving a push sideways on the rocker arm it should be firm, if you have a buggered lifter the rocker arm will be loose/sloppy and even though the lifter will/may pump up when the engine is running it may still cause that noise by not being able to take up the clearance under running conditions.

This is just speculation, as said before it is just guesswork of possible causes, but also a valid test as part of the process of elimination.

You are the man in the arena the rest of us are just well meaning spectators with suggestions.

No more pics too cold out there.

All lifters seem firm.


Checked a couple of other things.
There was oil in the harness, oil in the ECU plug. not actually inside ECU. Cleaned connectors.


I also removed the belt and see if the noise was still there. Yes it was.... the harmonic balancer had no play.


What was interesting was how rough the idle was without the belt. Is this normal? I check the nanocom, I was getting 20+ variances. As soon as i put the belt back on, the cylinder variances were with 1 or 2.


Using the large screw driver, i believe the sound is coming from the bottom end around cylinder 3 or 4.


Next for the flex plate inspection

[johnp38]

I also removed the belt and see if the noise was still there. Yes it was.... the harmonic balancer had no play.


What was interesting was how rough the idle was without the belt. Is this normal? I check the nanocom, I was getting 20+ variances. As soon as i put the belt back on, the cylinder variances were with 1 or 2

Well that has eliminated all the accessories and belt as source of noise, with belt removed you are running only on battery and that rougher running may be showing up a voltage/battery related issue affecting the idle, alternator runs the vehicle once started, battery optional.

Not relevant for now just hunt the noise down.

After checking all the items short of pulling the head off check compression on cylinders (not had mine long enough to do this myself) .

I think I read it is done via the glow plug holes for 1 - 4. No idea how to check 5 (will let you do the google search on that one)

You will have to decide down the track whether to live with it i.e. wait for something to go bang or fail to really point you in the right direction or pull things apart.

Also try and think back to when you noticed it, was it a sudden change or something that may have been creeping up on you?

Take notice of things like amount of blowby coming out of rocker cover in case of broken rings/piston (hence the compression check)

Remove sump and check internals that way before taking head off is another thing. And loctite oil pump bolt while you're at it if you go that route.

Anyway just go ahead and check doughnut bolts for tightness and flex plate for cracks as planned b4 going further.

A bit of broken valve can be bouncing around although that tends to be a more rattly noise but still in a rat tat tat sequence as piston comes up and down.

There are just so many variables but sometimes you find it quick sometimes not, just patience and work through a process of elimination.

I'm just waiting for Discorevy or someone else who works on these in a pro capacity to chime in, I am not a qualified mechanic just a diy with a bit of experience. And new to these donks but an engine is an engine you just learn their behaviour and idiosyncrosies.

[Bohica]

What was interesting was how rough the idle was without the belt. Is this normal? I check the nanocom, I was getting 20+ variances. As soon as i put the belt back on, the cylinder variances were with 1 or 2.

n

Maybe the belt on the harmonic balancer steadys it.
This may help, it has a TD5 technical manual.
Resources (http://discovery2a.com/Resources.html)

[TroyMortimer]

So i checked flex plate. Interestingly. Mine seems to be up side down compared to images found on the internet.

From what i could see no cracks on the right or left side. Could not see the bolt at the top. (I found guy showing how he diagnosed his toyota) tried the gear thing and didnt really change the sound.

Ive ordered a new oil pump bolt and gasket. Think I drop sump later, replace the oil pump bolt and see if any shaving are in the bottom of the sump. when i did my oil change I did not notice anything out of the ordinary.

Looking through Rave, I think i can access bearing caps, looks like you have to remove the oil pump then the stiffner plate.

This looks like a PITA.

Not that i have tools to remove the engine, but it feel like it a bigger project.

[simonmelb]

Have you double checked the easy things ie all ancillaries incl exhaust?

[V8Ian]

Engine mounts are pretty critical on Td5s.

[TroyMortimer]

Engine mounts are pretty critical on Td5s.
any tips on how to diagnose a failed engine mount. Also with the flex plate will this rotate with the flywheel? so the bolt at the top should become visable as the car moves?

[johnp38]

any tips on how to diagnose a failed engine mount. Also with the flex plate will this rotate with the flywheel? so the bolt at the top should become visable as the car moves?

Put car in neutral, chock wheels (sure you did this already but just rehashing)

You can spin engine by front balancer bolt or with screwdriver in flywheel teeth from down below and check the flex plate and bolt tightness as each becomes accessable.

Do a search on the Td5 engine mount check or someone will hopefully give you a procedure on here or have a read of the rave manual.

Normally I just look for the rubber to be collapsed on hydraulic ones and solid rubber you lift the engine a little and the break becomes evident.

Youtube is good for this becomes a pic is worth a thousand words and a how to video even more.

I can quite confidently say it is not your engine mounts, (until I am proven wrong [biggrin]) they don't make that regular type of noise, at idle in neutral the motor is sitting on them pretty still. You would see the motor bouncing side to side in rythm with the tap/slap noise if the mount had collapsed and it was metal on metal.

You are going to nut this out yourself in the end as you will soon learn the well meaning suggestions will get you nowhere most of the time because people will skim through the thread and not take it in properly or answer based on the first post and repeat what has already being suggested or done.

None of us are there on the spot and each of us has a different level of diagnostic skill sets. So all we can do is through suggestions at you and some will sound sensible and be totally wrong.

I am happy you are hunting this down, the more you do the more you learn and empowerment is a good thing. Even if it ends up at a shop what they find and you then going over in your mind of what you did will teach you how to diagnose better.

I would be doing all the checks you are doing anyway it is part of the fault finding.

[TroyMortimer]

not sure if these are cracks or surface blemishes. you have to zoom the photos.
I was originally checking the out side bolts but notice the line when checking the photos out. went a took a couple more. the last two images are about half way on plate.

I couldn't get my finger in there to feel for a crack

thoughts anyone?171803171804171805171806171807

[AK83]

defintely lines, not cracks.
Could be that one day soon it may crack under hard loading or something.
But as is, not cracked.

[WeekendWarrior]

Any luck?