Hi- I Am Looking Into Building A 1936 221 For A Roadster- Going To A 3 3/16 Inch Bore And A 4 Inch Merc Crank- I Understand It Should Be Sleeved When Going To This Bore Size- Looking For A Parts Source For Sleeves And Any Info That Could Help- Thanks Chuck
What 221, a '39-42 or what?? Most will go to 3 3/16 bore without problems or any need for sleeves. About half of factory 221's of this period actually came with special steel sleeves meant to allow quick rebuilding...these are actually nearly out to that bore by just removing the sleeves!
Hi Bruce- Thanks For The Reply- It Is A 1936 221- I Have Not Taken It Apart Yet So Am Trying To Do Homework Before I Do- I Was Looking At My Tex Smith Book On Flatheads And There Is A Article On Rebuilding A 221- It Was A 37 Block And They Stated To Avoid Overheating To Install Sleeves- I Dont Know If This Block Is Ln Or Not Yet- Thanks Chuck
On one of that age, do some homework on what it is and also have it sonic tested at multiple places. There are TWO 1935-6 engines, one with cast-in bearings and one with inserts. Many sources imply thin walls only capable of rebuild bores. I don't know myself, and I do know that some have been successfully bored to 3 3/16, but I would check thickness thoroughly before proceeding. Then--the two cranks are different cases! Cast bearing one has small mains, and the Merc crank needs DRASTIC rework. I don't think there's any metal for any real enlarging of bearing saddles. It has to be cut down so far that oil passages must be welded up and redrilled...consult a serious machinest on this. I don't have books here to check, but believe off the top of my head that the insert bearing '36 has same crank as '37-8 221's, and adapting late crank requires only simple cutting down of journals. Be sure machinest uses the cuts to establish big radii on journals. Ron over on Ford Barn has recently done crank cut for the later type setup.
thanks bruce- i have done some checking and the lb block has the insert mains- dont know what this one is yet- if it was a 37 engine it would be much better due to crank sizes- it is for a friend of mine who has a lot of eddie meyer stuff for one of these engines so that is the reason for choosing this engine- he already has the engine- i am talking to him shortly- i have a very good machine shop that can do all the work who specializes in large crankshaft work, boring etc- i will contact the ford barn for more info-thanks chuck