Hi guys
Can any one tell me what the clock like casting on the rear of the grey motor heads means? Is it a foundry ID number,year of manufacture or head version number? The head on my FE shows the pointer at the 2 o'clock position.Just curious as to what it means,as no-one has been able to definatly tell me what it is for.Any body got any ideas? Cheers Tony
Tony, There are three identification casting marks on the head, the first is a large single digit which is the year indicator, the second has a letter followed by a 2 or 3 digit number which is the batch number (you can actually see the screw heads in the casting showing that this was changed frequently. The last is a clock face with a moveable hand which I believe is the month indicator. I had a look at the 5 heads I have got here 3 say 2 o'clock, 1 says 12 o'clock and the other one says 4 o'clock. Based on this I feel a little sceptical about a month indicator as I would expect a little more variability than what I have in my small sample size. I will do a little more research on this and let you know. Ken
Hi Ken,thanks for that. I've got an other head with a 5 on the clock.It's got the nos. H5 4 then 1 near the thermo hole. Would that then make it a 1961 head as opposed to a 1951 ?
That's a very good question. The only way I know how to tell a 1951 head from a 1961 head (and 1952 from 1962 etc) is that FX heads only had 1 water outlet in the top of the head, from the mid fifties (I think) GMH changed the head design to include 2 water outlets, 1 at the front & 1 at the back. So if your "1" head has 1 outlet it would be 1951 or if it has 2 outlets it would be 1961. Ken