You'd hear the most ghastly rumbling sound if the main bearings were kaput enough for you to see the crank vibrating.

Maybe a touch of paranoia affecting my perception? 

Not sure if there are other explanations that make more sense?

 

Maybe it's torsional vibration that I'm 'mis-seeing'?

You're seeing undamped harmonic vibration, three cylinder engines are notorious for it.

So I can relax?

Really appreciate the input. 

You can relax, the job is done right.

        Hello mate,if I read this correctly, you have had the clutch problem for some time.Just make sure it hasn’t jiggered the crank thrust washers with the clutch problem pushing the crank over a long period of time.As in check the crank end float.

 

Edited 17 August, 20205 yr by maccy

Thanks, how?

Before I took the whole lot apart I did try pulling (by hand) on the crank pulley to see if there was any movement end to end; is that any use?

None was apparent by that method.

I don’t know this engine access wise so cannot help with that but how about a gentle tweek with a small heel bar or screwdriver on the front crank pulley or is there any access around the flywheel area.There is only supposed to be a couple of thou clearance when new, my 1.4 Tdi was so badly worn the unworn thrust fell out and I had to be recovered.I have never had a clutch in any car I have had over many years so I wondered if the person that had the car before me got rid it for that reason, as the car cut out on an island just after I bought it, and then again just after I had got back from Germany.I couldn’t sus out the problem until my friendly local garage towed it in and found the problem.New thrust set only got the end float back to about 015” from memory,so the car had to go.(the crank end float had taken the crankshaft out of the range of the crank speed sensor, hence no injection.)

You can also get someone to depress the clutch while the engine is running with you viewing the crank pulley with a light and mirror if necessary.

 

If you can see visible movement the wear is excessive, if you can hear the engine sound change its pretty bad.

 

fitting the thrust bearing(s) backwards will soon cause huge end float and destroy the crankshaft I've only ever done it once but it did have to be a race engine for a mate 🥴

Edited 17 August, 20205 yr by J.R.

I don't think this engine is getting any more work done to it for now, so apart from refitting the engine undercover, I think I'm just going to leave it to my partner to 'test' it fully by driving it as normal (did give her a little hint about not labouring it if she wants it last a while longer).

If there is anything dodgy with crank endfloat, there's nothing I'm able or willing to do about it, so I think I'd rather not know.

 

Will change the gearbox oil in a couple of weeks time, if enthusiasm returns, as the clutch issues did cause a few grinding engagements.

 

My own feeling is that it's fine and needs nowt else doing to it.

Aux belt tensioner is the one jiggling on my SDI, crank pulley seems at peace

May be normal since the torque 'spikes' on diesels are bigger than on petrol engines.  Does the alternator have a freewheeling pulley or fixed?

Should be a clutch pulley as it needed a special tool. Anyway few years ago it siezed and broke the tensioner.

Hope it will last few years more. The run out is only slight for now.