Knocking and banging, low power

[oddnumber]

Morning chaps, started the van this morning to drive it in to work. It was uncharacteristically knocking like hell and really low on power. Last time i drove it, it was fine.

The only thing I've done is try to loosen the crankshaft pulley. Could this have inadvertently retarded the timing? It definitely felt like an engine that was badly out of tune. If the timing has been knocked right back how much damage can be done by driving it like that for a mile or two?

[Ian Hulley]

The only thing I've done is try to loosen the crankshaft pulley. Could this have inadvertently retarded the timing?

Nope, right idea though ... go through what's changed

[oddnumber]

The only thing I've done is try to loosen the crankshaft pulley. Could this have inadvertently retarded the timing?

Nope, right idea though ... go through what's changed

my brain is frazzled enough by a 2 year old with tonsillitis!

i never have got the crank pulley off - nothing else could really have changed surely? I can't really see how what I've done could alter the timing, but it would give the symptoms i have.

[AdrianC]

Did you damage or knock an HT lead? Sounds like it's only running on three.

[oddnumber]

Did you damage or knock an HT lead? Sounds like it's only running on three.

Nope, all were tight Adrian

[kevtherev]

Wait.. knocking like on wood
or a
Tack tack tack.. dak dak dak noise
if it is thew latter your lifter(s) have drained down

take it for a run out for 20 mins..

[oddnumber]

morning Kev, definitely not a lifter noise. The van was down on power too, like it was right out of tune.

I can't see how me trying to loosen the bottom pulley could have nudged the timing, but the symptoms are similar I think.

[kevtherev]

With out being there it is very difficult to determine your problem.

[oddnumber]

With out being there it is very difficult to determine your problem.

Cheers Kev, thought I'd ask on the off chance. I'm sure it's timing related but can't see how what I've done could have an effect.

[CJH]

Did you disturb the vacuum advance pipework maybe? I've no idea how big an effect that would have, but it would affect timing.

[pionte]

There is no way you could have adjusted the valve timing , the crank pulley isnt adjustable and only runs the auxiliary belts. ( unless you have power steering ?? )

The ignition timing could cause a metallic sound if it was so far out to cause pinking ( pre detonation ) but there is a 10mm nut securing the distributor.

If the oil has drained out of the hydraulic lifters then you would loose power.... not that much but it wouldnt be as it should be.

Have you looked under the engine lid whilst its running? you havnt left a bloody great spanner in there somewhere? ( it happens ! )

[oddnumber]

Thanks chaps

Don't think I'd knocked a vac pipe, although the roughness in running would suggest more than a vac pipe being dislodged. Doesn't sound like drained tappets either unfortunately.

As for the spanner, anything is possible with me at the moment

[Highroller]

You haven't blocked or dislodged the air filter or any air feed to the carb. What about the choke?

[oddnumber]

You haven't blocked or dislodged the air filter or any air feed to the carb. What about the choke?

Not at all, everything looks connected still

[kevtherev]

I know you have dismissed lifter noise..are we to assume you have already had this with your engine.
A drained lifter would affect valve timing and would make the engine sound thumpy and it would run rough.