How much does it cost to rebuild a 1947 Flathead

okie pete

Junior Member
I have a 47 Mercury that was parked in a dirt floor shed in 1961 . Thankfully the hood latch was frozen in later years. The engine has Edmond heads and intake . I’m just trying to figure out how much I’m looking at spending on rebuilding the engine. Before I start gathering parts
 
It's really too variable to even give a rough approximation. It mainly depends on a couple of things : the present condition of the engine and how much of the work you can do yourself. Thd engine may be in fairly good shape and only need disassembly, cleaning, a hone job and rings, and a touch up on the valves. Plus a re-do of the carb and an ignition tune-up. Or, you could have an engine that needs everything (cracked blocks are notorious on these).

Bottom line? A grand if you have a basically good engine and can do a lot of the work yourself up to ten grand if you have a boat anchor and have to farm out all the work. Or even more if you want something really special (large displacement and/or a blower).
 
That's a long time in a dirt floor shed. I would look it over carefully to see what other problems you might have. Is the engine stuck? If it isn't, maybe you can get it running and assess it better. To repeat myself, that is a long time in a dirt floor shed.
 
Find out if there is someone in your area that has experience with flathead Ford engines to help you evaluate the block. If left with water in it, it may be cracked beyond repair depending on where you live. After complete disassembly and cleaning, the block needs to be tested in a few ways to determine if it can be rebuilt. Pressure test, sonic test, cylinder size and taper all need to be known BEFORE you spend money on accumulating parts or you may end up with a bunch of parts and looking for another block.













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My advice is pull the heads and see what’s going on inside the cylinders and valves. I learned my lesson trying to start a 239 that had sat for 10 years. We towed it around trying to get it to run and in the process busted pistons and bent rods on what could have been a good running motor if I had pulled the heads first. Some valves were stuck open and 2 cylinders were full of cotton lint from the seat. Never did work out how the lint got in there but both of those cylinders had the exhaust valve stuck open so my best guess is mice went up the exhaust pipe
 
Thank you everyone for your input
The engine is stuck . I have a feeling that it has a Merc crank in it . The late owner used to race the car . He and his brother liked fast cars
 
I thought you might have gotten lucky, but it looks like that isn't going to happen. Sorry, but you have just moved to the top half of my range. Hopefully, the block and crank are usable.
 
It already has speed parts on it that will fit on other blocks…….you say the prior owner was a racer….it’s definitely worth taking apart and see what’s up inside….start pouring your favorite penetrating oil in the plug holes now….it could just be the rings are stuck…..patience is you friend while taking it apart……what makes this fun is you never know what somebody did 60 yrs ago…..post some pics when you get working on it…..Mark
 
Aluminum heads will probably be toast if they didn’t prepare the motor for storage. Dissimilar metals will mean hard head stud to head removal . If water was left in it , well theres a chance the blocked cracked .
First, add marvel mystery oil to all the cylinders, I add old motor oil to fill the crankcase a few quarts above the full mark , I even remove the upper hoses , block the lower hoses and add old oil in the WATER jacket . This may help with the head bolts.
Add your location, someone that knows flatheads could live nearby.
Good luck
 
It mainly depends on a couple of things: the present condition of the engine and how much of the work you can do yourself. The engine may be in fairly good shape and only need disassembly, cleaning, a hone job and rings, and a touch up on the valves. Plus a re-do of the carb and an ignition tune-up.

And a gasket set. It is always nice to be able to take an engine apart and discover that the above is about all it needs to run well again!

as tubman sez: "and how much of the work you can do yourself."
 
I just hope that dirt floor shed didn't promote to much rust on the underside of things. When I pull an engine I remove all the front sheet metal to make things easy to reach. Seems obvious you'll be doing brakes along with new lines and hoses. Then the radiator is in your hands too. If it needs kingpins, spring bushings.....everything is right there. On the pickups it's easy to remove in one piece with two guys, one at each wheel well. Then start pulling heads and intake and poking around inside that engine. If it requires pulling, that's a snap at this point. I've probably done this with ten trucks in the last 15 years.
 
60+ years stored in a shed is a long time. I am often a break it loose and give it a try kinda guy-but on this one I would not attempt it. Take it out and take it apart. By some miracle you might just be out a gasket set, but I doubt it. The oil has probably turned to tar. Rings and/or valves likely stuck. Don't break some potential good parts for a shortcut IMHO.
 
Asking how much a flathead rebuild will cost is a lot like asking how much dinner is going to cost. Do you have the ingredients? Are you cooking it yourself? Are you going out? For fast food, or fine dining? In a small town, or the big city?
 
Asking how much a flathead rebuild will cost is a lot like asking how much dinner is going to cost. Do you have the ingredients? Are you cooking it yourself? Are you going out? For fast food, or fine dining? In a small town, or the big city?

And are you going by yourself . . . or do you have a flathead date to do with you! Some dates are free - most tend to cost a bit! LOL
 
Thanks for everyone’s input and humor. I’ll continue to keep soaking nuts and bolts until I have time to take the engine apart
 
Do you know why it was parked— perfectly good cars are not usually parked and stored.
The cost also depends on how good you are at scrounging.
 
My '48 took about $4,800 as it was in rough shape. I had a machine shop I trust do all the work on all the internals and I did the rest.
 
Whatever you decide to do, just make sure that once you decide on steak, don’t give up and settle on Spam. (Flatheads vs. SBC)
 
I used to have pictures of a mouse nest in two cylinders of a Flathead stored in a warehouse. The choke was open and the mouse craweled down the carburator in to the cylinders.
 
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