Hi all. I have been using a restored 1986 MCAL as my daily machine for the past 5 years. Unfortunately my brass grouphead top plate is wearing out by creating a depression where the roller meets the end of the roller platform at the end of the downstroke. This seems to prevent water from entering the group unless I really push hard and force the roller to travel "uphill" through the concave depression. I contacted stefano at espressocare and he says the new top plates will not fit my 1986 machine. Has anyone had this problem and found a solution? Anyone have any used spares in good shape? Do I need to buy an entirely new group assembly?

thanks much for any assistance,

Todd

Look in the buy/sell forum here, number9 had a bunch of parts for sale though I'm not sure what he has left. Or, maybe you could hit a hardware store and find a thicker roller or rig something to place under the existing roller to fill in the wearspot?
Good luck no matter.

I am not sure what would happen if one were to remove the piston assembly and then flatten the worn surface either by milling or by careful (and tedious) filing with a flat file. Has the roller been turning freely? If not there would be rapid wear to produce this condition. Has it been kept lubricated?

Should flattening fail, the obvious solution is to be sure that the surface is flattened evenly as described above and then take a piece of appropriate metal stock, preferably stainless steel, and mill it to the form of a small rectangle of correct thickness, and attach with two small stainless screws.

On giving more thought to this problem, it seems to me that you could also use a piece of brass stock to make a shim. It would be easier to file or sand a piece of brass to the correct size than stainless. Someone with steady hands could also use a device like a "Dremel" tool to make such a shim. This would take a bit more time with stainless than brass. You can easily find countersunk 3mm stainless screws. A small milling machine would be easiest, but with patience and care one could make such a repair without one.

Hi guys thanks for the quick responses. Based on your advice I looked at the roller and to my surprise it was not rolling freely. I disassembled it and lubricated with Dow 111 and performed a citric acid descale for good measure which I hadn't done in over 2 years. Now the lever is moving more smoothly and I'm getting good flow without an aggressive push at the end of the stroke. Not sure if the low flow was due to roller friction or some scale in the siphon tube but I did notice some minor pitting where the axle rubbed against the roller so disassembly and lubrication was definitely a good suggestion. I hope the roller lubrication and freed up motion will help prevent further damage to the top plate and that I won't have to repair the slightly concave area.

Thanks again, Todd

Here is a pic of the concave area that I am hoping not to have to
mill out or shim.