Rockers hitting the rocker cover?

[Paul V]

I put my mini away about 2 years ago with a knocking engine, it started knocking after going to the goodwood mini track day with lsmoc, not having a runabout at the moment I decide to go have a look at it, well I started it and it ran ok, bit misfire and the exhaust seems to be blowing slightly from the centre branch, it didn't seem to be knocking till I had driven it, now it started knocking when hot, seemed to be louder when I took the rocker cap off, so with it running I went to take the rocker cover off, as soon as I loosened the rocker cover bolt the knocking stopped. so do I just fit a new thicker cover gasket and realign? it has high lift rockers from a sport 5 cooper and a very big valve head, still have a stand rocker cover but might go have a look in my garage to see if I can find a old alloy one knocking about. never had that before, thought I'd had most mini problems before lol.

[wildoliver]

Is it the tappet screws that are hitting or the valve end of the rocker?

[Paul V]

It's hard to tell really as there aren't any marks in the rocker cover, I did have to shorten the push rods when fitting the head due to it being skimmed so much I couldn't get enough adjustment on the rockers rightly. the compression was quite high but I had the chambers opened out by Bill Richards who originally did the head for a 1380 to give me enough volume.

[wildoliver]

ok another q, have you got a massive amount of screw thread coming out of the rocker?

[Paul V]

there is quite a bit of screw coming out the rocker actually, I think it might be hitting the back of the cover looking at it, funny it only seems to be once the car has warmed up though.

[MR2Mike]

Possibly it's only just clearing when cold, but when the engine warms up the expansion of the push rods just makes the adjustement screws touch?

You could just take a bit off the top of the adjuster screws I suppose.

[wildoliver]

Either buy shorter adjuster screws from mini spares, or take 5 mmm off the top.

[jacobyte]

Some years ago I had this problem. So I ground out the inside of the rocker cover with a grinding-ball drill-bit to create some clearance. Did the job perfectly.

[Paul V]

Well I've put the car back in the garage, it'll probably stay there for another 2 years lol. Forgot to tighten the rocker cover before driving it though so a little smokey under the bonnet opps

Need to sort out the drive shaft seals too. of all the pain in the arse jobs on a mini this needed most of them, drive shaft seals, speedo cable, manifold gasket, trying to get the electrics working and a few other minors bits. Reminds me why I stopped using it lol

[jellison]

Really common problem with high lift rockers if the base head has been skimmed more than a little!

The Rocker posts are designed for a std head decked height so when this is hcanged you have to simulate that thinkness back below the pedistals.

You need the 3mm steel rocker pedistal posts from Minispeed (£8) - when fitted job done.

[8 port]

It is quite common for the rockers to touch the inside of the rocker cover.Before you start machining and buying parts try pushing the rocker cover backwards towards the baulkhead as you do it up this normally gives you enough clearence to stop the touching.

[Paul V]

Cheers I'll give it a go next time I have it out the garage.