Clutch rattle

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vansolo
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Clutch rattle

Post by vansolo »

Just got my JX replaced with a 1Y using all the JX bits including fuel pump and injectors, inlet, turbo, etc. New clutch installed and after about 50 miles this rattle started when engine is idling, pressing the pedal makes the rattle go away and if I rev the engine above +/- 1200RPM. Spigot bearing was installed. Any ideas?

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Aidan
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Re: Clutch rattle

Post by Aidan »

it's not uncommon with any of the 1.9 diesels, there's either a pulse on the input shaft, ie a clutch fault or a slight misfire at idle or the pulse vibration from the pump is transmitted down the engine and gearbox and the whole is able to vibrate sufficiently to cause the 1st reverse synchro to bounce between the gears which are spinning in opposite directions causing it to clack as it spins one way then the other. That only applies to 5 speeds and syncro gearboxes so if it's a 4 speed it will be a diesel misfire imho
also some clutches are more prone to it than others, the LUK and miscellaneous boxed ones being more susceptible than the Sachs in my experience
Obviously this engine set up was never designed to go in the van so you don't have the benefit of VWs tuning of the harmonics and dynamics, taking in all aspects of the mounting and drivetrain to come up with a quiet set up. And the JX pump and injectors weren't designed to run the 1Y, how have you set the pump up ?

I'd look at the gearbox mount and engine mounts, particularly the gearbox mount. Then I'd put a petrol engine in, as one never comes across this problem with petrol engines, I have had gearboxes back under warranty with this fault and fitting them in my van with a petrol engine has proved the fault isn't gearbox caused, but it is the box that is making the noise, or it maybe the clutch itself, again you just never get it with the petrol clutches which have less damping built into them unless they have a broken damper spring which only happens when they are very old and rusty and in need of replacement anyway - if you stethoscope it you should be able to find the noise source, if it's in the front section of the box then it's the synchro bouncing, if it's from the bellhousing it's the clutch

vansolo
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Re: Clutch rattle

Post by vansolo »

Thanks for the very detailed reply Aidan. :ok Probably like you said its got to do with the pump setup, at the moment the idle its not has smooth as I would like it to be, so that then is reflected on the clutch/box. Another clue is for example when approaching traffic lights even slowly in neutral and just idling the rattle doesn't happen, the rattle only starts when the van stops.

boatbuilder
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Re: Clutch rattle

Post by boatbuilder »

I have a similar rattle on mine. 1.9d AEF recently fitted. New generic clutch and release bearing fitted, new spigot bearing too. Goes away completely when you press the clutch pedal. Only happens in neutral.
https://youtu.be/4RfiPC4DaQU" onclick="window.open(this.href);return false;

Sent from my SM-G920F using Tapatalk
1984 1.9D (AEF Code) T25 tintop

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