29 replies to this topic

[mini danny]

hiya i was driving my mini when it lost power was missing a beat and then starting making a very loud knocking noise could be herd from 30 m away i found it wasn't firing on cylinder 1 so i pulled the lead off and the knocking noise was alot quieter and power didn't change to when noises started what could it be its got fairly new leads caps rotor arm i can see these causing the lose of cylinder one but what would cause the knocking noise? ????

Any help would be very helpful many thanks Danny

[LiamB]

Check and clean all cylinders, once done, just rev it and look to see if there is anything abnormal going on in there.

[Cooperman]

More info is needed here.
What sort of 'knocking'?
Is it smoking out of the exhaust pipe or through the oil filler cap (emove it and let the engine tick-over).
Take the plugs out - what do they look like?
Are you losing water?
Take the rocker cover off - is a rocker broken?

[mini danny]

Its hard to explain the knocking it sounds like 2 bits off metal not being bashed together just tapped but very loud if you get me and not losing water or smoke at exhaust

[Cooperman]

Take the rocker cover off and check for a broken rocker.
If that's not it, then you had better remove the head and check the piston on no.1.

[Sam Walters]

Raise the rpm to around 2000-3000 rpm, pull the plug lead off when the engine is running (Wear some stout rubber gloves)

If the noise goes away i`m pointing my finger at a big end.

Also beaten too it, quick check of the rocker too. Its not uncommon for rocker shafts to break.

Edited by Sam Walters, 23 November 2011 - 12:24 AM.

[mini danny]

Ill check Rockers in morning in bed now it only makes the knocking under load if im going steadily alone it will stop completely but as soon as i put any amount of accerlation it starts again :\

[Cooperman]

Raise the rpm to around 2000-3000 rpm, pull the plug lead off when the engine is running (Wear some stout rubber gloves)

If the noise goes away i`m pointing my finger at a big end.

Also beaten too it, quick check of the rocker too. Its not uncommon for rocker shafts to break.

Yes, could be. I had a situation once when the tip of a plug broke off and wedged itself under a valve seat. Really puzzled me until I got the head off.
I think remove head and check in the top end. Then, if nothing found, it'll be engine out for detailed inspection.

[mini danny]

This may sound stupid but ild have no where to start to remove head and defo haven't got a torque wrench to put it back together


Danny

[Cooperman]

If it only knocks badly under load it does sound like a bottom end problem on no.1 big end.
To run a Mini you need to be able to do most basic things, like head off, engine out, etc, yourself or have deep pockets.
if it's a big end, then it's straightforward once the engine is out and off the gearbox, een if it needs a crank re-grind. The parts themselves are not expensive, but the labour would be high.
Anyway, check the rockers, although if it's worse under load that is an unlikely cause.
Where do you live? Maybe one of us could come round and take a look to help you.

Edited by Cooperman, 23 November 2011 - 12:35 AM.

[mini danny]

Hiya ya im learning how to do most bits I've learnt the body work before the engine but looks like im gonna need to learn quick lol ill check everythink tomorrow and see if it can be sorted i was hoping to use the mini until my estate had been finished and then rebuild this one

[mini danny]

And im from leamington spa and how long would it take to remove head check and put back together

Danny

[Cooperman]

Doing it for the first time, assuming a decent tool kit, about an afternoon maybe a bit more. You do need a torque wrench. But if you take the head off and find nothing, the next step is engine out, for which you need a hoist and a load of special tools to get it all to pieces.
We are here to help and I don't know who lives in your area who could come and give you an opinion and some encouragement.

[mini danny]

I have a fairly big tool kit with loads of tools ill pop down to halfords and get a torque wrench if i can't solve it tomorrow


Danny

[mini danny]

Had a looking this morning and cheeked all the Rockers/ springs all fine no cracks nothing but it is now firing on all cylinders but still has the powerless and knocking but i think its my valves as only noticed the tapping now speeds up with the engine speed and also it sounds like the noise at the top of the engine so tomorrow and Friday im off work and will take head off so might need some people advice is its ok


Many thanks i appreciate it