Broken Crankshaft?

[Chrishutt]

Yesterday I was returning from a long motorway drive in my R4 GTL when suddenly the engine stopped with the usual metallic knock you get when something nasty happens to a motor.

I have just had a look and can see through the oil filler cap that the valves are moving, as is the distributor so not timing chain. Also, with the car in gear turning the key drives it forward. Out of gear the starter motor turns freely as if there is no compression on any of the cylinders.

Could this be a broken crank? If so is there any point in attempting to replace it or will the engine be beyond it?

 

[angel]

I think it is very unlikely that the crankshaft is broken (however, after seeing the recent post with the broken distributor drive, never say never!). Maybe bent valves from timing chain jumping teeth? (equally unlikely as its length is fairly short). Pre-ignition that burnt a hole in piston? I would first do an engine stripdown to find what the fault is, then decide if it is worth fixing it (in many cases, with secondhand parts, it will be worth!).

 

[Chrishutt]

Thanks angel for your advice. I assume from what you say about bent valves that this engine has a non-clearance head and that pistons will hit valves if the timing chain jumps teeth. This could explain the complete loss of compression on all cylinders. Oh dear

I live in France so bits should be fairly easy to find I guess. If I can't find second-hand parts are new parts still available? This is the first time I've had problems with my beloved 4L so have had no need to find spares for it.

Next step then is to remove the head and have a look and hope for the best.

 

[angel]

Yes the 1108 engines can bend valves if something goes wrong with the timing. I have never heard of one doing it though.
You can find new parts for this engine easily.

 

[Bluebell]

Chrishutt, whereabouts in France are you? We've got a neighbour with a spare 1981 TL if it's any good to you.

 

[Chrishutt]

Thanks again angel. See what you mean about the broken dizzy drive on that other post, never say never. As soon as the rain stops I'll start investigating. Is the timing chain at the back of the engine? ie. does the engine need to be removed to get at it?

Bluebell I'm in not-so-sunny Normandie, about 600km from you. Bit of a long drive but if I get desperate... Thank you.

 

[angel]

Yes you are right...the engine needs to be removed to reach at the timing chain... :-(