This report is from David Crabtree in early June 2021. Original style tappets From Moss Motors for MGA and early MGB engines appear to be raw-forged or as-cast on top end, not having the top socket finish machined to accept the pushrod. The ball end of the pushrod does not fit to seat properly in the ball socket, like the female cylindrical diameter is too small to allow the pushrod ball end to enter.

Above, new tappet on left, and original tappet on right.

Below, Original tappet with a dab or grease, before and after inserting and twisting the pushrod. Notice the grease nicely distributed around the pocket.


Below, New Moss tappet with a dab or grease, before and after inserting and twisting the pushrod. Notice the grease in the pocket was not touched when the pushrod ball end could not fully enter the pocket.


New push-rods (Moss #460-610) from Moss do fit part way into the socket, but still do not seat all the way down into the socket to mate with the spherical surface. So matched sets of Moss tappets and pushrods also do not fit to work together.

This problem was first noticed on August 12, 2020. When contacting Moss technical support David was referred to a technical support advisor named Lawrie, who as it turns out doesn't actually work for Moss now but may be called upon as needed for advice and support to customers. Lawrie was very nice and referred the problem to someone who does work for Moss. This was in August of 2020. After three months David had heard nothing so he emailed Lawrie again. Lawrie contacted Moss again, and that time David received an email from Kevin Dodd at Moss saying that he would look into the problem. Another six months has past (nine months total now), but still no follow-up from Moss. David contacted Lawrie again June 10, 2021. He said that he to was very disappointed with Moss.

The tappets received from Moss were labeled "Made in India." The Moss catalog states: "Tappets and pushrods changed in length and diameter of the spherical mating surfaces at engine #15GB5504. The later parts which we supply may be used in earlier engines in pairs only." Unfortunately the current Moss parts do not work in pairs of their parts either. So far it is not know if the new Moss pushrods are correct or faulty parts. We still need to try the new pushrods with the original tappets.

Moss Motors has been notified (again) on June 13, 2021. My admonition is to not buy this part from Moss Motors until this defect can be fixed.