Let me start out by saying I understand I would prefer if my block had no cracks. But I remember reading someplace that the cracks between the water jacket and the bolt holes don't matter. I see no cracking that goes to the cylinders but I have three or four water jacket to stud hole cracks like this on my block. Is this block still worth sending out to get magnfluxed? Posted using the Full Custom H.A.M.B. App!
You read right. Those cracks are nothing. Not even worth trying to fix. The head gasket will take care of that.
Good news then. Looks like I may have found an Ok block on my first try. Took a gamble on a 8ba out of a 50 F1 with the trans and bell housing. Hopefully it will still check out when it gets to the engine shop
Suggest you pressure test and magnaflux before spending big dollars. As stated the crack you have shown is not a problem, very common.
For sure that's my next move. I'm just glad it's so far so good Posted using the Full Custom H.A.M.B. App!
Rumor has it there was actually a guy at the Ford plant whose job it was to put those deck cracks in the blocks before they left the foundry. As everyone has said they are harmless you could go one step better and have them heli coiled doing that would eliminate any pulled threads if you use head bolts. If you decide to use studs that would be better I have found those threaded holes to be weak at times when torquing using head bolts.
I have always found that blocks from trucks and Mercury's are a better than from Ford cars. Why? better cooling from bigger radiators. I even have one from an 8RT that doesn't even have the "part number" cracks! Your block looks pretty good to me!
One problem I see is the hand grinding you're doing on the deck surface. That'll get you in trouble real quick.
Well, my case may have been a rarity but one of my engines had the exact same cracks.And i ran it. I had a $12 thermostat destroy that engine.The thermostat closed up and that crack opened up and became a high temperature water blaster,melting my head until it ate it away to the cylinder edges,and then lined the two cylinders with molten alloy. Lesson learned the hard way i don,t run thermostats now or i always drill holes in them if i do. Johnny
I've never, ever seen a flathead Ford V8 block with miles on it which didn't have cracks. That one in the photo is no problem. Those which go from the valve seats to the cylinder, that's another story. jack vines
Even those 3M discs remove material... we used to get heads from the dealership for repairs and every head the guys cleaned up with the 3M discs needed surfacing... they remove more metal then u think!
Those are so common Ford gave them a part number. To find a flathead without a crack or two would be very rare.
Just remember if you mag you're block make sure they demag it good or else the residual can screw with your gauges.
A also common place for cracks is from the valve seat down into the port and you don't have the valves out in your pic so take a look there also. T
The only justification for using a flathead Ford is to restore an old one to original condition. I've never seen one that didn't have cracks in the block. And when you can buy a brand new Chevy long block for $1600, why would anyone want to build one for a hot rod. If you're a die hard Ford guy, Windsor crate motors are cheaper than building a flatty. There's no way to make a flathead make more power than a small block Chevy or SB Ford.
Nice first post. Dig up a 4 year old thread to make disparaging comments about stuff that is the essence of this place. You are clearly on the wrong board.
Those little cracks in the stud bores will actually leak under pressure. The water will creep up the head BOLTS ('49-'53 type fasteners) but if the '32-'48 studs and nuts are used, (and the studs sealed) the problem is usually solved. BUT, as an old flathead guru once told me (Harry, at Automotive Industrial Supplies) "After any appreciable machine work on the flathead Fords, Mercurys, and Lincolns AND Cad flatheads, prior to starting and warming up the engine, add a small can of heavy duty block sealer to the cooling system. It is good insurance." 1980: A friend had a nice Nitro black lacquer '32 Tudor sedan he had just finished. He came to the shop, asked me to take a look. The 284" Rod Furtado-built flathead had spit out some water in droplets...out the side louvers some whitish-looking stains of water had settled, in thin streams...both sides. The Edelbrock heads were bubbling slightly, maybe 8-10 bolts per side... I knew Furtado's practices, so the engine assembly would be thorough...no need to tear a head off, not yet, anyway. I drained the water coolant, added a can of block seal, removed the hood, and told him to drive it, at least 30 minutes...He did, and when he returned the bolts were no longer seeping. I had also cleaned his beautiful Rootlieb hood sides, and we set the panels back on. He drove the car a lot, so periodically I'd ask him how it was doing. He had added Prestone as directed (by me) and said there was no more problem.
Make sure when any of your guys are cleaning a flathead to NOT retap the stud holes. Most of our tap sets will cut those threads too loose, and then they will weep more. (Wisdom conveyed by Bruce Lancaster, wish he would come back) If you need to clean rust, cut a lengthwise groove in an old stud and run that up and down the hole a couple times.
Looks ok here. I bought 6 flathead Motors this summer. All of em had cracks like you said. One didn’t ...the one with the 4” merc crank and it was a merc motor . Thank you!!! Build it.
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