21 stud rebuild sugestions

Firepower flyer

Firepower flyer

Senior Member
Hey everyone I have a very tired and very leaky flattie in my 35 5 window and I would like to put a fresh engine in it.Heres what I'm planning on doing and if someone can chime in with any sugestions or tips on what to do or not to do would be great and if there's a decent book on doing a stock rebuild I would like to pick that up if someone knows of a good one.So the coupe is all stock and still wears it's factory paint and I intend on keeping that way.I think some where along the way it had a 36 engine swap into it,atleast thats what I can determine from the codes on the heads.What I would like to do is build another motor that I currently have and then swap it into the car so it's not taken apart for any amount of time.So the engine that I have is also a 36 unit from what I can tell and have been told so I would like to use that.I have completly tore the engine down and did a pretty good once over looking for any major cracks or problems,so far so good.So we have a local acid dipping faclity and thats where it's at right now so I can start with a nice clean block.I will send it to my buddys machine shop for magnfluxing when it's done being dipped.Once again if theres any tips or recomendations I would love to hear them.This is my first flattie rebuild so I don't want to mess it up,the machine shop does do a few flatties but I still want to be on top of it so theres no mistakes.Thanks in advance
Joe
 
I'll post some pics of the engine that I have apart right now,keep in mind this is not the one out of the car.The one in the car has the same casting codes as the one in the photos,at least the driver side head is the same but the pass side has different numbers on it,not sure whats up with that.I didn't find lb stamped on the intake surface but maybe after it's done getting acid dipped I'll see something.



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Couple more crappy cell phone pics,One more thing when I pulled the rods and crank it appears that it has insert bearings not the babbit style.


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If you want to make it more correct, go with flat top pistons and 40- heads. preferably aluminum.
 
[FONT=Times New Roman, serif]Joe, from what I can see in your Avatar picture, it looks like you have a nice original car and I would encourage you to keep it as original as possible and drive it that way after you get your engine rebuilt. I personally enjoy seeing an original survivor more than a high point restored car and I believe others feel the same way. First, you can't really tell the year of some of the early 21 stud engines by the numbers on the heads because those heads were swapped around so much back in the day. If the main bearings in the block you are rebuilding can be easily removed, that would mean it's an LB block. Not all LB blocks were stamped LB on the intake deck. When you remove your old engine you may want to also consider removing the transmission and go through it to check gears, bearings, spacers, etc., for wear. Replace any worn parts and install new gaskets. Also check the universal joint and rebuild/replace if necessary. 10 to 1 if you don't go through the transmission when the engine is out, you will wish you had later. If you are a member of the EFV8C/A and someday wish to show your car in the original/Rouge class, you may want to keep your engine and transmission looking as it does now. In other words, don't clean and paint the outer surfaces of the engine and transmission (It may be too late for that if you have already had the block acid dipped) If you need to bore the cylinders in the block you are rebuilding, I would suggest not going over 0.060" since the cylinder walls in those early blocks are thin to begin with, not counting the corrosion that has occurred on the outside of the walls from water/coolant. There are several good books available on rebuilding flathead's. Ol' Ron who posts here wrote a book called "Nostalgia" that is still available on CD. "Rebuilding The Famous Ford Flathead" by Ron Bishop is another good book that is still available. Some others are: How To Rebuild A Flathead Ford V-8" by George McNicholl, "Ford Flathead V-8 Builder's Handbook" by Frank Oddo, and "The Complete Ford Flathead V8 Engine Manual" by Tex Smith.[/FONT]
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I'm sure others will chime in here with lots of good suggestions. Good luck! Keep asking questions here and keep us informed on your progress.
 
Thanks for the replys!John you bring up a lot of good points,I did't even think to touch the trans,but maybe I'll open it up and take a look.You hit the nail on the head with leaving the engine looking the way it does.Thats what I wanted to do but when I decided to build the other engine I kinda had to dip it with the condtion of the water jackets.The engine in the car I know is good,I've had it running with coolant for 15 years and it's never rusty looking.I assumed that the engine was changed when I looked at the head codes but maybe it's still got the factory motor in it.I'm thinking of maybe switching my plan and pulling the stocker out of the coupe and rebuild that one and leave it looking as is.The car has such a great look to it I would hate to ruin that untouched feel.I know someone rebuilt the engine in that car at some point there is a stainless tag on the driver side bellhousing that gives the specs of the rebuild,if I remember correctly it's 30-20-10 so probablly 30 over 20 on the rods 10 on the mains??I'll have to decide on what to do but I would like to keep it looking the way it does,I don't want to be bummed out when I open the hood and see a fresh "looking" motor if you know what I mean.If it turns out to be a 35 engine what do I do about the babbit bearings?I like the thought of insert bearings but maybe that because I know little about the babbit.I geuss I have to make up my mind on which engine to use, it has been bugging me and I'm glad you brought it up.
Thanks
Joe
 
you know the sad part is the machine shop costs out here on the east coast are so high its less expensive to buy a 24 stud from the midwest shops then to rebuild a 21 stud.

i would modify it for the full oil flow through an oil filter, even though this isnt original it just is too good of an idea to ignore

i added a PCV set up to mine and went with an alternator

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Yes, do one over & swap em, still takes longer than you think, always something...
 

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I'm fairly local to you and do many early Ford engines each year. I also do an insert main conversion for the 32-36 engines if you're interested in not going the babbit route? Contact me and feel free to stop by the shop anytime!!! I have a 35 I'm working on right now with the block almost ready for assembly if you want to check it out?
 
Fox Valley Hot Rods said:
I'm fairly local to you and do many early Ford engines each year. I also do an insert main conversion for the 32-36 engines if you're interested in not going the babbit route? Contact me and feel free to stop by the shop anytime!!! I have a 35 I'm working on right now with the block almost ready for assembly if you want to check it out?
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Thanks pm me your info please
 
If you want to clean out the water passages without touching the outside of the block: put the heads back on, set the block vertically on the bell housing area, and fill the water passages with a diluted mixture of phosphoric acid and water. When it stops fizzing, dump out the acid and neutralize it with a baking soda and water solution.
 
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