M51 (non) Running Issue

AJB2494 said:

Thanks for this explanation.

Could a dodgy crank position sensor cause this kind of issue? I've noticed there is no plastic plug on the flywheel timing pin hole also, which could be letting debris in, could this interfere with the sensor?

Many Thanks, Alex.

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Decent diagnostics should tell you everything you need to know. Even though you can't read live data as the engine does not run long enough. Faults should be logged. If it is getting the right amount of fuel at the right time it should run. Diesel engines are pretty simple beasts in that respect. It's all the electronic control that buggers them up. Take the injectors out and see if any are wet.

Small update - Got out to the car today and tried a direct feed of fresh (newly bought) fuel to the FIP, the results were largely the same, must have fed over a litre of fresh fuel in. A couple of times it fired a moment or so longer than the video shows, in all cases it cuts out in exactly the same way.

Battery is dead now, however when cranking it near the end I got the starter motor 'clicks', however it seemed to power through it then started turning again and fired (only to cut out once more).

Regards, Alex.

Update (with some hope!): I disconnected the downpipe at the cat and tried running it again, the same occurred with exhaust leaving at the join and backbox.

I then thought about re-trying stuff, so unplugged the crank sensor and got it to start and run very rough for perhaps 6-7seconds (felt like forever!) with lots of knocking until it went into a fast idle, at which point I thought it best to shut it down.

It just so happens I know someone who has a Range Rover with blown head gasket who is willing to lend me some parts (with a view to buying them) to get it going again. Going to try crank sensor and injectors and see what happens!

Regards, Alex.

I tried another crank sensor and it's the same, tested with multimeter and resistance is identical on both so assuming that it's working.

Turns out the No.4 injector off his RR has a slightly different multiplug, the locating tab on the plug is off-set whereas mine is central therefore it won't plug in unless it is butchered (can't justify ruining his working injector). His engine is the non-EGR/non-MAF version.

I haven't tried any of the other injectors yet, but when I loosen the high pressure pipes off one by one and try it, the engine still cuts out but if memory serves me with no.2 or 6 loosened off it stops 'softly' as opposed to with a large knock.

AJB2494 said:

I tried another crank sensor and it's the same, tested with multimeter and resistance is identical on both so assuming that it's working.

Turns out the No.4 injector off his RR has a slightly different multiplug, the locating tab on the plug is off-set whereas mine is central therefore it won't plug in unless it is butchered (can't justify ruining his working injector). His engine is the non-EGR/non-MAF version.

I haven't tried any of the other injectors yet, but when I loosen the high pressure pipes off one by one and try it, the engine still cuts out but if memory serves me with no.2 or 6 loosened off it stops 'softly' as opposed to with a large knock.

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Plugs are different on #4 injector but the actual injector is the same according to Bosch and a mate who has tried both.

Datatek said:

Plugs are different on #4 injector but the actual injector is the same according to Bosch and a mate who has tried both.

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I tried the other injector with some wires rigged up to the plug and the issue appears to still be there, although only got one start before the battery was flat.

Regards, Alex.

Sorry to have to say this, but isn't about time you got someone who knows what they are doing to look at it?

wammers said:

Sorry to have to say this, but isn't about time you got someone who knows what they are doing to look at it?

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And get a decent battery

wammers said:

Sorry to have to say this, but isn't about time you got someone who knows what they are doing to look at it?

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In hindsight, perhaps I should have done so a while ago.

Thanks for the help, if I find the solution, I'll be sure to post it incase it helps someone in the future.

Regards, Alex.

Might not be that much expertise on the IoW?

Grrrrrr said:

Might not be that much expertise on the IoW?

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This is very true, just full of retired, closed-minded people trying to ignore the rest of the world.

AJB2494 said:

This is very true, just full of retired, closed-minded people trying to ignore the rest of the world.

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As soon as my horse comes in I'll be down there to join them.

I've had the car looked at and the diagnosis is timing jumped. Crank located at TDC and camshaft located with tool but fuel pump cannot get anywhere close to 0.9mm lift needed.

AJB2494 said:

I've had the car looked at and the diagnosis is timing jumped. Crank located at TDC and camshaft located with tool but fuel pump cannot get anywhere close to 0.9mm lift needed.

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Favourite sprocket to jump is crank sprocket if engine is turned backwards. Anticlockwise looking from front. If that happened cam timing would also be out. Unless the cam has been reset. Engine should NEVER be turned backwards.

Hi AJB2494

Looking at your video, its looks very similar to my motor a few months ago. Same symptoms, same sound, same smoke....

More about it here:
https://www.landyzone.co.uk/land-rover/terrible-sound-from-the-engine.283038/
and here.
https://www.landyzone.co.uk/posts/3527653/

My motor had jumped one tooth on the lower chain. This happened when I turned the starting key, saw the glowplug symbol coming on and released the starter key at the same moment. The starter had probably not turned the crankshaft around enough to overcome the first compression stroke, and the build up compression in the cylinder reversed the direction of rotation of the crankshaft enough to make the chain jump one tooth. Also the brief turn of the crankshaft did not build enough oil pressure to firm up the chain tensioner.
You can not see this one tooth jump unless you have the camshaft blocking tool and the locking pin in the flywheel. By just looking at the cam-lobes it is not obvious.

Major work to get everything sorted out.
You must pull the head and the sump to gain access to the chains and tensioners.
Better change all wear parts when you are down there.
(chain tensioner, chains, chain-guides, gaskets, camshaft sprocket bolt, headgasket, headbolts, consider doing the serpentine belts, water pump and thermostat too)
Also a few special tools are worth to buy, as the high pressure pipe key, 17mm I think, strong torx cup's as the head bolts are torx as is the camshaft bolt.
Could also be worth the money to have the head vacuum tested before re installation. Just to check if any of the valves has had an unpleasant encounter with a piston.

Good luck

Larsern

Larsern said:

Hi AJB2494

Looking at your video, its looks very similar to my motor a few months ago. Same symptoms, same sound, same smoke....
...Good luck

Larsern

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Larsern,

Thanks for your post. It is a big job to replace, the garage I had it looked at in said in the order of £1,000 to pay them to do it, given the time involved, I have the car back now and contemplating what to do next. I have a few of the tools already such as the dial gauge for timing the pump and fuel pipe spanner, but don't have the cam locking tool or tensioner pins etc. I think alone the parts are going to be a substantial cost so I have to decide what is next, begin the process myself or scrap it.

Regards, Alex.

AJB2494 said:

Larsern,

Thanks for your post. It is a big job to replace, the garage I had it looked at in said in the order of £1,000 to pay them to do it, given the time involved, I have the car back now and contemplating what to do next. I have a few of the tools already such as the dial gauge for timing the pump and fuel pipe spanner, but don't have the cam locking tool or tensioner pins etc. I think alone the parts are going to be a substantial cost so I have to decide what is next, begin the process myself or scrap it.

Regards, Alex.

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The locking tools are about a hundred quid on ebay,