babbit engine

[als roadster]

i recently posted a thread if thats what you call it ,but just wanted to thank everyone for their responses. thanks alot. Well anyway i pulled off my head to see what kind of condition motor was in.I live in hawaii and i bought this A on ebay that was a consignment so i dont have any contact with previous owner i have tried emailing and calling but no response yet.Anyway took head off and dropped oil pan. As i said earlier i want to put HC head ,cast iron headers and webber carb. Engine looks very clean and compression is at 60 lbs in all cylinders.my question is how can i tell between a babbit engine or inserts. Also should i do a valve job or lap job or leave it alone and just install new head ,headers and carb ? Thanks alot Aloha. Al

 

[Kevin in NJ]

My opinion is that you need to tear the engine apart and check everything.

You want to make it go fast and if you are not sure it has been put together properly then it may bang real fast if something is not correct.

Because you are asking questions that an experienced engine person would not ask I would think you should enlist an experienced person to help you with this endeavor. You need to start with checking the crank. Is the flywheel on center (should be less than .001" off center) are there marks indicating the flywheel has been balanced to the crank? It has to be balanced to the crank and reasonably on center or it will help to beat up your rear bearing. Not to mention you loose HP to making vibrations. You also need to check the crank has the 3 mains cut on center. They are frequently not ground on center.

Weigh your rods and your pistons. Ford had the rods +- 1 gram at each end and the whole rod piston units should be within 4 gram.

Measure the clearance on the valves. If they are not close then you might guess someone did not set them up right. Look at the valves and the seats you should see signs of seating all around. Measure the total lift of the cam.

Measure the cam bearings and see how good they are and do not forget to look at the dist worm gear. That is sometimes worn quite a bit.

If you have babbitt then it should not come out (it sometimes does). Babbitt should be tight to the saddle. Push on the edge of the babbitt, it should not squeeze out some oil. That indicates the babbitt was not peened properly. Look for cracks and oil grooves. Should have oil grooves and no cracks. Should also be some holes for the oil to get in that lead up to the valve chamber.

As you can tell you need some micrometers that you can trust. A dial indicator can be useful too.

Sadly, you all to often find some pretty fundamental problems on 'rebuilt' engines. What I list above is just a small part of stuff to look for in an engine. Lots of little stuff can add up to a marginal engine that gives lots of grief.

 

[Kurt in NJ]

Since you have the pan off it is probable that you can tell if it is insert or babbitt by looking at the rear main thrust, many of the insert conversions use a brass thrust bearing for the rear main, with babbitt it should be more of a silver color.

With 60 lbs compression you probably don't have any valve seating problems.