Model 31 rocker oil feed

[petert120r]

Completed latest rebuild last week and on starting the engine with the rocker covers off, waited patiently for a few minutes but no rewarding spray of oil. Everything else fine - good return and weepage from top crankcase bolt when loosened. Tested for blocked oilway with compressor nozzle in top gallery and tissues over the rockers - all blown off by the pressure.

Stripped it down this morning to find thatI could poke a pipe cleaner through the drive side crankcase top oil gallery directly into the pushrod hole, explaining the lack of feed. Examining both the timing side case and another spare drive side crankcase half I found what looked to be cylinder head oil restrictor plugs before the pushrod hole, thereby forcing the oil up the cylinder barrel and head internal oilways.

Can't find any reference to plugs in the crankcase in any of the bibles or on the forum so my questions are:

Are they in fact head restrictor plugs or something else, i,e. solid ones? What is the general view of oil restrictor plugs in the heads? I have none on these heads and AMC seemed to change their minds every five minutes on whether they should be fitted or not.

I await your collective wisdom.

[1608]

I believed that the restricted oil-way was to ballance out the flow to both sets of rockers and also to prevent overoiling them.It would probably take longer to reach them on a dry engine than perhaps you have allowed for.
I have just cleaned the heads and oil-ways on my G12 and was surprised to see a pile of dry carbon-like powder come from the oil way through the barrel when poked with an old spoke,and that is ater soaking in petrol.
Good luck and keep us posted

[1608]

It also appears from your description of the metering plugs that you are unaware that they do in fact have a very small hole of approx 1/64" or less.This may be blocked.

[Duncan]

I am not sure what year they changed but the original/early metering plugs were not drilled but had a flat on one side.