I ended up w/ 2 engines from m38a1 vehicles. Therefore, 2 oil pumps. After the overhaul, am deciding which oil pump to install. One is exact copy out of the supply manual pn7376907, A131 stamped on cover, and it is in good shape passing all the tests in the ovhl manual. Two is stamped USA1 on cover and is different in that it has a drive gear and slave gear for the internal pump and I cannot find any number stamped anywhere. Two also looks good and was working fine when removed. Would like to know something about Two and, if possible, which would be the better to install given they are both in good shape. Am learning a bunch from you folks, and will say thanks in advance.
Rapid
53 M38A1
XAir (Ultralite)
oil pump id
Moderators: TomM, Moderator, wesk