Cylinder Heads

[David.H]

My 1927 AD has a head marked XL 1253 ED. It has brass hex plus in it (what for? ...priming?) ...I am not sure how sound this one is. It has a suspicious lump near where the horn bracket is bolted on and I think it may have an old problem.that has been repaired/bodged...
There is some witness of water appearing near the lump, and indeed possibly from up a couple of studs... No serious water leak though, nor overheating, just a bit of gurgling when stopped after a brisk run.
Compression is healthy cold (75-80) I will check it it hot. Yesterday, out in the heat I had a bit of missing at "high" revs for the first time
Which head could I replace it with if it turns out to have a problem?
David

[Robert Leigh]

Basically any of the A7 heads will fit, but if you go for a late Ruby type you will need two longer studs at the front and a later type water outlet. There are still plenty of heads around the style of yours: the brass plugs are where the priming plugs were fitted on the very early cars. PM me if you want to discuss more; I can probably help.

[Tony Press]

I would suggest do not fit a what is commonly known here as a '1937 head' (actually a 1936 head) to a light shaft motor - I believe the 6 to 1 is a bit much after 5 to 1 on the bent wire shaft

[David.H]

Thanks for that information!
D

[Rogerfrench]

I would suggest do not fit a what is commonly known here as a '1937 head' (actually a 1936 head) to a light shaft motor - I believe the 6 to 1 is a bit much after 5 to 1 on the bent wire shaft

Don't disagree with the suggestion, but with the assertion that it's actually a 1936 head.

Back way back when, the year associated with a car was the " model" year, not the year it was made, or registered, or anything else. And the 1937 head was for model year 1937, even though the cars went on sale in the autumn of 1936.

The model year designation is still common here in the US.

[Alan]

‘‘Tis here in the uk too

[Tony Press]

I would suggest do not fit a what is commonly known here as a '1937 head' (actually a 1936 head) to a light shaft motor - I believe the 6 to 1 is a bit much after 5 to 1 on the bent wire shaft

Don't disagree with the suggestion, but with the assertion that it's actually a 1936 head.

Back way back when, the year associated with a car was the " model" year, not the year it was made, or registered, or anything else. And the 1937 head was for model year 1937, even though the cars went on sale in the autumn of 1936.

The model year designation is still common here in the US.

True but from memory the head casting is marked 1936 !