Just started the engine up with plug leads 4 and 6 the wrong way wrong…Ran for 30 seconds until I realised something was wrong.

Now with the plug leads correct There is a BAD sound coming from the rocker gear/head area on that side.


In terms of damage –

What’s the best I can hope for?

What’s the worst I could have done?

Will strip the head down tonight. – hope its just a bent push rod or two.

Paul

I'd be suprised if just running an engine for 30 seconds with 2 plug leads wrong would cause any damage really.

are you sure it was ok before doing that?

would have thought it would run badly and then be fine afterwards.

I guess a bent rocker or pushrod etc is possible.

let us know how it goes!!

Once had a customers Range Rover in for a service that he said was running well that had 2 leads on wrong . Putting them on correctly in ran even better . That had no noises after being run for weeks with the firing order wrong. Double check your firing order Paul .

pull out one pug at a time and ground it and turn it over have a look at the plug also for any damage.i cant see it doing any damage as its just fireing at the wrong time so theres a good chand it had no real compreshion when fireing

there is no way you can bend a rod mate

Just had the rocker covers off..

The push rod on the exhaust valve on cylinder 8 has some up and down play in in. All the others are solid.

Had the rod out and its not bent . All I cas think of is the lifter has had all the oil pushed out of it and has not yet primed again. They are Rhodes lifters.

You can feel the lifter compress when you push down on the push rod.

Any thoughts or help.

Paul

Having 2 plug leads round the wrong way won't kill the lifters - just sounds like you've got an un-primed one. Slack tappets do make a god-awful noise. Assuming the lifter isn't dead and the oilways are clear then it will go away when it eventually primes up -but may take some time. Took a 10 minute thrash on an Ecotec that had been stood for 3 months with no oil in it...

The noise is probably the lifter bottoming out, thats all..

The final cylinders are the ones that become starved of oil and the cam loses its lobes, end of the gantry and all that.

I suggest you pluck off the inlet and valley plate, pop out all the followers and blow all the oilways out with an airgun and access the state of the cam.

It could just be that due to lack of pressure its not pumping up at all, what is your oil pressure and timing cover, early ones are not the best and wear badly, you can reface the end plate on a piece of glass with some wet and dry.

Regards Mark

Car had not been used for a month. Before that it was running fine. just had the leads off to help access when changing a core plug.

will give it a chance to prime the lifter in the morning and hope it does.

Paul

Check the torque settings on the rocker shaft bolts. If one of these is loose, it will flex and make a hell of a noise.

It if hasnt been run for a month id run it up and let it prime up.

How long did u run it with with firing order correct?

It wont bend anything getting the order wrong. May burn a valve or piston if its left wrong for ages. Not 30 seconds.

all sorted....

gave it a chance to pump up the lifter and the noise vanished. seems to run well again

Paul