Broken down - Spun bearing

[Quinten]

Had to call the recovery truck today as I'd broken down just outside Silverstone .

Had driven the car last night and there was no sign of any problem, and when I left from home everything was still fine too.  As it was early I stopped at a McDonalds for breakfast, about 9 miles into the journey.  15 minutes later, the car would not start, as if the battery was flat.  Lights dimmed when pushing the starter button and it took a push start by a friendly passer by to get the engine running again.  After 4 miles I pulled of the dual carriage way on to a slip road and then there was all of a sudden a loud knocking noise coming from the engine, and then it started to buckle a little bit.  Pulled into layby straight away and switched the engine off.  Called recovery and got home within the hour.

 

At home I had a first look at checked what I could visibly.  Noted my oil and coolant were both on minimum, so topped them up again (first time since engine conversion was completed).  Re-charged battery, although the charger told me it was full anyway.

Then starter the engine and was greeted with this noise...

 

[Captain Colonial]

Sorry to hear of your troubles mate.  

From the symptoms and noise... lunched alternator?  How does it sound if you take the alternator off the belt?

[Quinten]

9 minutes ago, Captain Colonial said:

Sorry to hear of your troubles mate.  

From the symptoms and noise... lunched alternator?  How does it sound if you take the alternator off the belt?

Hmm, I'd never attributed that noise to the alternator...?  No idea how it would sound, but I guess that is something I can try can't I?

[Captain Colonial]

It's just the symptoms prior to the noise all point to a charging system failure.  Couldn't start it, lights dimmed when cranking, etc.  Might be starter has come loose and is fouling the flywheel or similar.  The temptation is to think of the worst, but always start with the cheap and simple first.  What's the oil pressure like?  Drop the oil and check for swarf as well.  Hope it's something simple - good luck.

[Trevor Little (Trevturtle) - Treasurer]

1. Plugs out to check if it's anything obvious.  

2. Turn over without the plugs to see if its compression related.

If it stops  with the plugs out that's a lead  to follow... If it still knocks  compression check, then top off to check the cams. 

Also a  screwdriver to your ear on the head/block etc and listen  to where the knock is will help

Take your time.. slow and methodical  is best...... don't  run it too much if possible..  it's  a loud tapping on the video

[Kit Car Electronics]

Sounds bad enough that it should hopefully be obvious, like a broken alternator bracket or dropped a mounting bolt out?

[Kit Car Electronics]

I love the game of 'guess the noise'...

It'll  probably turn out to be something unexpected like a dead cat with a hammer stuck in the alternator belt

[CraigHew]

Well that sounds a lot like mine did when the battery didn't have enough juice left to turn the engine over.

My charger too said fully charged, but it wasn't.

I'd chech the battery voltages first off, it may be an easy fix although it doesn't account for the break down on the slip road.

[Terry Everall]

I would be worried that engine coolants were down to minimum!

Also sounds a bit like valves hitting the pistons

[Captain Colonial]

Believe you me, if the alternator has come loose on the mount and the belt is still spinning the pulley, the noise of the cooling fins clattering against the mount or something else is quite a cacophony.

[KugaWestie]

How was the oil pressure? Low oil level is a concern

I hate to say it but that sounds like a big end bearing has spun

This is what an mx5 engine sounded like with a spun shell

 

I would start with a long screwdriver to your ear touching the engine in various locations to see where it is loudest

[Thrustyjust]

Sadly, I am with Gary on diagnosis. Was the coolant and oil at maximum before you started ? I hope I am totally wrong Quinten.............

[Terry Everall]

Gary and I think exactly the same but I hope we are wrong

[Quinten]

Cheers guys, your questions/tips are well appreciated.  I played @Gary (KugaWestie) - North Oxfordshire AO's video back and my wife immediately said, that sounds like yours 

 

Coolant drop could have been air expelled from the system, as I've only recently filled everything up (when I had to replace my flywheel/clutch/etc) so was not at 'level' yet.  Engine oil level was higher when I checked previously than what it was when I checked it this morning, so that's a little worrying of course.

 

I will check alternator, mounts, battery etc tomorrow, but the pit in my stomach also says it is engine related, not ancillary.  As I'm no mechanic, what does 

1 hour ago, Gary (KugaWestie) - North Oxfordshire AO said:

big end bearing has spun

mean in terms of salvaging the engine?  I'm sort of assuming from the title of Gary's video that it means engine out and rebuild from the bottom up?

 

And just to cover the obvious, it's not a 'sticky' valve or some other 'Silvertop known problem' right?

[KugaWestie]

I would do the checks on your list.

If that bears no fruit, engine running and screwdriver to the ear. My bet is that it will sound louder at the bottom of the engine just above the sump joint.

If that is the case, drop the oil and look for a silver sheen in it, like this

If if you get the above, I am afraid it will be engine out for closer inspection