Intermittent Td5 tapping is back and louder!

[Sitec]

So, it's rattling under load again! 100kph with turbo singing and the top end metalic tap appears. Back off the throttle a few times and it disapears. Performance does not change, I just know that the tapping is not gud and I'd rather investigate it before it does damage. Has anyone ever replaced the hydraulic followers because of this? These are the only thing I can think of.. (assuming that if an injector fails, it fails!). Thoughts please. Thanks.

[Sue]

I don't know the answer... but I'll bump your post up just in case someone else does.. :)

*bump*

[CraigE]

Are you sure it is engine noise?
The R380 gearbox is renowned for getting a tinny sounding rattle at certain speeds, in 4th & 5th and under load. Just another suggestion. Must be something to do with how the stick sits in the gate. My Defender does it at 80-90kmph in 4th and 90-100kmph in 5th.
My RR and Disco both had R380s used to do it as well. Can be quite annoying at times.

[LOVEMYRANGIE]

I'm surprised driving a Fender you can even distinguish a new rattle.
I'd be more worried that if the rattle went away, something's actually fallen off!!! :Rolling:


Using Capitals, the difference between helping your Uncle Jack off a horse or helping your uncle jack off a horse...

[fatman]

You said under load?
Maybe leaking-cracked exaust manifold?
Mine sounded like a dead-dry-crazy spining bearing...

[isuzutoo-eh]

Symptoms do point towards an exhaust leak, warped or cracked manifold, buggered exhaust gasket...my Isuzu has a terrible under-load tappety-tap-tap but after checking tappet clearance it turns out it's a gasket leak, under the manifold so evidence is hard to see.

[Sitec]

100% certain that it's not gearbox or exaust as it's a metalic tap that is internal. (nearest thing that sounds similar is striking two teaspoons against the rim of a tin of dog food in time and fast!!!)... When running at a constant engine speed the 'tapping willl come lightly at first then get louder after a few seconds. Not being game to keep the throttle down, I back off. The tap stops instantly and will usually not come back when re applying the throttle. Being an Ag Engineer, I know my way around diesels, and having had the head off this vehicle soon after I bought it (it tapped several times before head removal), I've had the cam, followers and injectors out. One injector has been replaced. I'm 90% certain it's an injector or hydraulic follower but wanted to see if anyone has had the same prob b4 I order 10 hydraulic followers! Thanks!!

[goingbush]

I would not pull it apart unless I was 100% sure it was engine noise,
you could put it on a dyno to simulate the load @speed & listen for the noise with a stethoscope etc ,

[PhilipA]

At say 2000RPM, each cylinder would be rising 33 times a second.

IMHO This does not qualify as a "tap" ,as it would be more a "buzz", so I would be looking at something going a lot slower, like something after the diffs.
Regards Philip A

[Sitec]

It's a fast tapping for sure, and def engine related. Dip the clutch, whilst still at speed (difs,props, and trans still turning) and the tapping (buzzing) will slow untill it clears then all is good again for 50 to 100 kms then it'll re appear. Sometimes it won't clear and a few revs with the throttle will clear it (Tapping increases and decreases with engine speed and then goes). 99% certain it has something to do with injectors or hydraulic followers. One injector died soon after the head was skimmed... Alli swarf inside! Back to you guys and galls!

[djam1]

Nanocom and cylinder balance test might indicate something

[bitdist]

Mine tapped under load at one stage, but I could hear it sometimes at idle as well. It turned out that the chain tensioner had jammed so the chain was moving around and making tap tap noises.
It is easy to find out at least.
If you look at the front of the engine, about half way down the left hand side is a large nut. Undo it and pull the chain tensioner out and see if it still goes in and out

[Sitec]

Thanks both, timing chain adjuster is a good start, will check it out, and yup, it's due a plug in as no 3 injector has not been 'set/recognised' by the ECU yet. Just got to find the time to get down to PCB! Thanks guys!

[bushrover]

My TD5 Defender had a similar tapping noise. First time it was a cracked heat shield on the left side gearbox mount, bloody drove me nuts for ages trying to find it. Would only make a noise when backing off. Second time was the turbo cover cracked and vibrating around 2000 rpm. Third time was the fan belt tensioner pulley bearing starting to fail and it took me a while to realise the tapping noise was happening only when the air con compressor was running. Fourth time the weight thingy on the back of the transfer case broke a bolt and came loose. fifth time I will do as someone has already suggested and wait for whatever to fall off.

Rick

[Sitec]

Back again, and now 100% set that it's the hydraulic followers at fault as there's a new fault tied in with it all. When cold, the vehicle starts and runs well instantly on all 5 cylnders. When warm, the engine fires up on 4 cylinders with a resounding/timed thumping noise coming from the snorkel suggesting to me that one of the followers is draining down allowing one inlet valve to leak. This goes away after about 5 seconds. If it was an injector fault, there'd be no noise from the air intake.......

[djam1]

Have you had the head done?
I have seen this on TD5s with a head gasket on the way out
they leak a little water into the cylinder and it does what you are saying
Is it using coolant

[Sitec]

Yeah, did the head gasket about 10000km ago, soon after I bought it. Since then it's not used a drop of coolant. The tapping was there before and after I did the gasket....

[phuma]

@sitec - what was the solution to the tapping noise?