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Discussion Starter · #1 ·
The cam pulley for the fuel pump isn't turning when the engine turns over.

I was driving at about 60-65mph, there was a 'thud' and the engine shut down (symptoms exactly the same as when the fuel pump belt and tensioner let go a week earlier, right down to the fault code (low fuel pressure or something)).. pulled onto the grass verge and awaited recovery.

Got the rocker cover off earlier this evening and the cam is ok, not snapped. The pulley has about 5 to 10mm of movement in it.

Now here's what I don't get.. if the chain has snapped, sufficiently for the cam to not rotate, surely the pulley/cam should just spin without the constraints of the belt? If it's not spinning, the chain is still preventing it and turning the engine over would spin the cam/pulley too?

Does that make sense?

Is it safe to crank the engine a couple of times with the rocker cover off to see if the cam spins?

If I'm thinking right, what else could stop the fuel pump pulley/belt from spinning? This is potentially a £1500 question, the cost of supply and fit a replacement engine.

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Discussion Starter · #4 ·
Rotate engine by hand always.
I did that before.. way before.. when I was trying to get the fuel pump off.. can't really do that now because the fuel pump belt isn't fitted and I cannot access the crank pulley.

and if it is stuck don't force it because that means the pistons are touching the valves...
It's not stuck. It turns over normally.
 

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oke as i thought it's not there, software is old... i need to update it... that said... from what i read the pump chain if snapped doesn't mess with the timing, it just means you need to remove what is in the way to replace it... and the parts aren't that expensive either decent priced replacement I found was 120 pounds...
 

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Discussion Starter · #9 ·
oke as i thought it's not there, software is old... i need to update it... that said... from what i read the pump chain if snapped doesn't mess with the timing, it just means you need to remove what is in the way to replace it... and the parts aren't that expensive either decent priced replacement I found was 120 pounds...
The pump runs off a belt, not a chain, and isn’t the problem.
The problem is that the cam pulley that runs the pump belt doesn’t turn (which presumably means that cam doesn’t turn either).

Logic would suggest that either means the cam has snapped or one of the cam chains has snapped.
The cams look ok.

But if the chain to that cam has snapped to the point it no longer ran it, I should be able to turn it and it not feel like it’s turning the engine over, right?
Well I can’t.

Doing the chains on these is about £600 parts and 25 hours labour.

These are not my chains, my engine is still in the car…
 

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As your thread title says "Anyone fancy a punt" so here's my punt!
Has a sheared woodruff key been ruled out? You say the engine turns over by hand and the cams haven't snapped and the pump not turning. Or is the pump pulley on a taper and the bolt has come loose?
My knowledge of this particular engine is very small so if you like you can overlook what I have mentioned.
 

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The pump might have a woodruff key and since the pump isn't turning ( but the engine is from your explanation) it might be just that... here is a picture of a new one

Yeah i typed to fast in my previous reply I full well know the pump is ran of a belt.

If i'd have the same problem i'd take the fuel pump off and check to see if that is the problem.

Actually scrap that about the pump it might be a broken chain tensioner that is stopping the camshaft from moving... thing is, you can't just replace one part you'll need to replace the lot... but still cheaper than getting another engine. I highly doubt it is the chain that went to be fair but you'll only know what went f you tear it down and investigate.
 

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Discussion Starter · #12 ·
The pump might have a woodruff key and since the pump isn't turning ( but the engine is from your explanation) it might be just that... here is a picture of a new one

Yeah i typed to fast in my previous reply I full well know the pump is ran of a belt.

If i'd have the same problem i'd take the fuel pump off and check to see if that is the problem.

Actually scrap that about the pump it might be a broken chain tensioner that is stopping the camshaft from moving... thing is, you can't just replace one part you'll need to replace the lot... but still cheaper than getting another engine. I highly doubt it is the chain that went to be fair but you'll only know what went f you tear it down and investigate.
It’s nothing to do with the pump, pump belt or pump belt tensioner.
This is all on the cam side.
Which is why I’m struggling.
There’s just not enough of the typical busted chain (and/or tensioner) symptoms for us to fully buy into that.

Replacing chains and tensioners is not cheaper than dropping another engine in… it’s about a grand dearer.

Problem with tearing it down is it requires removing the engine, which we can’t do.
Time and space is something we don’t have.
 

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well if you won't diy than yes engine replacement is the cheapest option... I don't see any other thing that would stop one part from moving in there unless the cam that stopped moving is blocked by a piece of metal/plastic and in most cases it's metal that stops it from moving while the rest still moves. Looking at that picture of all the chains it can only be either a chain that is broken/ a tensioner/ a chain guide (most likely) or the whatever holds the cam-sprocket on the camshaft has sheared off and is now stopping it from turning... that said you would be able to turn it (until the valves hit the top of the pistons on that side)
 

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Discussion Starter · #14 ·
well if you won't diy than yes engine replacement is the cheapest option... I don't see any other thing that would stop one part from moving in there unless the cam that stopped moving is blocked by a piece of metal/plastic and in most cases it's metal that stops it from moving while the rest still moves. Looking at that picture of all the chains it can only be either a chain that is broken/ a tensioner/ a chain guide (most likely) or the whatever holds the cam-sprocket on the camshaft has sheared off and is now stopping it from turning... that said you would be able to turn it (until the valves hit the top of the pistons on that side)
The valves don’t hit the pistons… this is partly why I’m a little perplexed.
And… the cam (that doesn’t move) is still connected to the chain (well, it sounds like it anyway). But when the engine turns over the pulley doesn’t spin so the cam isn’t moving.
It’s not making sense to us.

And it’s not that I won’t diy, it’s simply not possible.


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I'm a bit lost here.

Chains from the crank to the cams, then there's a sprocket on the cam that drives the pump that'll be mounted externally to the chain covers?

What doesn't spin? Cam sprockets will be woodruff key'd or conical and torqued up. If the chain is intact the woodruff key is snapped or the bolt has lost tension. Then the sprocket will be similar story?
 

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Discussion Starter · #16 ·
I'm a bit lost here.

Chains from the crank to the cams, then there's a sprocket on the cam that drives the pump that'll be mounted externally to the chain covers?

What doesn't spin? Cam sprockets will be woodruff key'd or conical and torqued up. If the chain is intact the woodruff key is snapped or the bolt has lost tension. Then the sprocket will be similar story?
Cam chains are at the back, pulley on the front that drives the belt that drives the fuel pump.
I can’t check chains or tensioners without removing the engine which isn’t possible (I also don’t have the finances to spend on garage fault finding missions)

Pulley on the front doesn’t spin when the engine turns over.

Conical, not woodruff, on both fuel pump and cam pulley.

All bolts tight as f***, possibly even tighter than that - I had to get a 2ft bar on them to crack them off.
Nothing is slipping.

The cam (with the pulley) has about 5mm of back and forth movement (without the fuel pump belt attached).
 

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So when you rotate the engine both cams rotate as expected? The pulley on the front (which will be conical to the nose of the cam) is slipping? But the cam is intact and rotating?

Picture of cam with movement?
 

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Discussion Starter · #18 · (Edited)
So when you rotate the engine both cams rotate as expected? The pulley on the front (which will be conical to the nose of the cam) is slipping? But the cam is intact and rotating?

Picture of cam with movement?
I don’t know if both cams rotate, I can’t rotate the engine without cranking it on the key - no access to the bottom pulley (even my low entry jack is too thick to get under the car).

The cam is definitely intact, can’t attach the vid clip of the cam movement- I’ll get on my laptop and see if I can upload it to YouTube.

I know the cam pulley for the fuel pump doesn’t spin because Kirsty was in the car turning it over (on the key) while I was prising the fuel pump belt cover open enough for me to see the belt.

 
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