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MG Midget and Sprite Technical - Rocker Gear Mystery

It's only a mystery to me.

I've just opened the bag marked 'Rocker Gear Fastenings' - three years after I put them away - and I can't remember what some of the bits are for.

Four studs and four spring washers, but six nuts.

Two threaded spacer tubes.

I can see that the longer studs must be for the cover fixings, in fact there's a note to that effect in my job book, but why the extra nuts, and the spacers? I expect I will work it out when I get there, but I thought I would ask you now, to put my mind at rest.

By the way, I also have nine head studs, nine nuts, and five flat washers. I can see the marks of nuts alone on the pedestal clamping plates, so I guess they fill the role of the missing four flat washers. I can only assume that the high torque on the head studs stretches them sufficiently to preclude loosening, while the pedestal fixings need the extra help of the spring washer.

Hope your weekend weather is better than ours.


Nick and Cherry Scoop

Maybe the 2 spare 7/16" nuts and spacers go onto the front and rear rocker studs to provide a stop for screwing the rocker cover bolts down onto.
GuyW

Thanks very much, Guy. I had forgotten that those rocker cover bolts are female-threaded. Also, I have the ribbed alloy cover, so maybe some non-standard adjustment was needed.
Nick and Cherry Scoop

All tosh from me, as so often. The bolts are bolts, and they must screw into the threaded tube, which is no doubt brought to the right height by the extra nuts.

BTW, I'm not wedded to my Ashley GT ali rocker cover. Does anybody on here actually have an Ashley?
Nick and Cherry Scoop

I used to :o(
Dave O'Neill 2

Hi Nick
Any idea why you have four grub screw retaining plates? We usually see this when roller rockers are fitted and rockers need elevating to ensure correct rocker geometry, they are placed under posts rather that the usual one on top. If this was the case I would expect five retaining plates?
Peter
Peter Burgess Tuning

No idea, Peter. Derringtons must have put them in, as expensive washers. I don't particularly remember them during dismantling, but the marks on the pedestals in this picture show them as having been on top.

Derringtons used a Morris Minor engine for this build.

Nick and Cherry Scoop

Expensive washers then :)
Peter
Peter Burgess Tuning

I remember seeing the 4 plates on all the early 803 and 948 engines. they seemed to have only one on the later 1275/1098 engines.
Bob Beaumont

Bob

That sounds about right. I think the A35 had four plates, but they did use alloy pillars IIRC.
Dave O'Neill 2

Ah yes they did have alloy pillars so the 4 plates makes sense. I suspect they were reused on the steel pillars as well.
Bob Beaumont

This thread was discussed between 22/07/2017 and 25/07/2017

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