Series 2a engine

Evening all,

We are currently looking at the possibility of buying a spare engine for our 2a, our 2a is a wedding car so if for any reason we had a problem we would have a back up. I am trying to find out if ours is a 3 or 5 bearing engine. We have found a 5 bearing engine to buy which has been re-built, are the 3 and 5 bearings are a straight swap?

Many thanks in advance

yes they are ,the main difference is 3 brg are imperial bolts ,5 brg metric,

Look above the sump on your engine, 3 brg has smooth sides whereas 5 bearing has strengthening webs cast into it