Good evening, Needing some Flathead Ford expertise / thoughts. I have a recently rebuilt 1950 Flathead Ford V8 long block. A shop with a good reputation in the area did the rebuild and I helped with the ***embly process. Anyway, I was putting in the distributor today and wanted to make sure the engine was at TDC on #1 cylinder. In the process of trying to turn the motor over by hand I realized that the engine will only rotate 1/2 the rotation and then gets stuck in either direction at 2 and 7 o'clock. The engine has no spark plugs installed, no intake, and no bellhousing/******. The engine has a Mercury 4-inch crank, 1950 F1 pickup truck oil pan, and new Speedway motors oil pickup. I know the engine turned over freely without any bind before the oil pan, heads, and timing cover was installed. The heads are late EAB cast iron heads, the cam is an Isky Max-1 with .365" lift, and the valve are stock diameter. The head to valve clearance was checked on the #1 piston with 0.0100" and 0.080" clearance on the intake and exhaust valve repectively without any gasket. There only three things I can think of: 1.) Valves are hitting the head (only checked #1 piston)? 2.) Mercury 4-inch crank is hitting something like oil pickup? 3.) Cam is rubbing against cover? Any thoughts anyone? Very frustrating and I am putting quite a bit of force on the crank and it does not want to rotate beyond the points I described in either direction. Thanks, Josh
Don't do that seriously, I hope you did not bend a valve, or.. Valves hittiing or the pickup hitting. Take it apart, pan first then heads,
The things that lock up firs when left sitting and with no ***embly lube are the valves. Not at all likely valves are hitting heads with that combo. Pull front cover (39 cent gasket, 30 seconds hard work...), remove the 4 bolts on cam gear, and see if it will rotate. If so, valves are sticking. If wrenching it hard, I would expect oil pickup interference to feel rubbery, as the thing would bend... It is possible to damage stuff if wrenched too hard against stuck valve. Pulling heads is not too hard, and there really isn't any reason to replace the head gaskets unless they are actually damaged.
Is the flywheel installed? If so ...look for a bolt that's too long hitting webbing? Don't know flatheads, may not even have webbing around the crank end, but have seen this happen once on a '57 Ford (one flywheel bolt 1/4 " too long). Just a thought.
I had the same thing happen to me. I was panic stricken for a while until I found it but it was not on a flathead. If it's on an engine stand mounted in the conventional manner, you may want to check further before you tear it all apart.
".010 is not enough clearance. Want around .050" REAL good call here...did not notice that point! Not only is that inadequate completely for running clearance, it means you have trouble nearby right now! The heads are domed...if cut enough to register 010 in the middle, most of the dome in the head is GONE and the flat area is touching...I think this has just moved up to #1 thing to check! If heads are cut and not redomed you need multiple checking points.
call the dude that did the rebuild and have him check it out. not being familiar with flatheads it sounds like stuck valves because anyone ***embling a motor always hand spins it after every ***embly step,at least the guys i have watched do mostly out of habit.
You guys rock. Started with the oil pan, nothing hitting. Then cam cover, nothing hitting. Valves are hitting the heads! The exhaust valve had 80th and the intake had 100th (not 10th) on #1 valve without a gasket. I have no idea how the valves are hitting on the other cylinders but they are without a doubt (exhaust). Probably not going to sink any more money in these old cast iron heads, not that I had a lot in them but I did pay for them to be baked, blasted, and painted (looked really nice for cast iron). Next step is to remove the heads and make sure no valve are bent with me wrenching on it. Possible but hopefully not as I did not go nuts when it got stuck. After looking at the damage if any the next step is probably some Edelbrock or Offy heads. Only bummer (besides the price) is the block is not relieved and I know the after market heads really benefit from a relieved block. Thanks again, you guys rock! Josh
you might want to keep your eabs and have the valve area modified a bit. those are some nice heads and will save you some money and get good performance. talk to the shop and see what they have to say, just mho.
"...and I know the after market heads really benefit from a relieved block" My belief is that the air basically wants to go UP and can only turn toward the piston area slowly from its trajectory off the seat angles...Ron Holleran's approach here was to keep the stock transition bowls around the valves and relieve the heads up there...that ceiling is not high enough, the floor is not too low...that's my belief, I think supported by Navarro, Francisco, and Holleran... Remember you want to check clearance with gasket, you want at least two check points per valve because they are canted. You want multiple checks on piston area, because curvatures of dome to roof may not match neatly. A FIRST check can simply be rotating with heads sitting loose with no gaskets; if no move, you are safe, but likely will want to determine actual clearance next and tighten piston down to 040 (too loose here is bad) and lower lid on valves even more than that. You may not be able to get to ideal in all areas (the killer race guys start with no chambers at all and hand-carve!) so get piston right as first goal. All numbers ***ociated with catalog listings of your new heads will likely be wrong...
Finally had time to remove the heads tonight. The pistons, not the valve are hitting the heads. Valves have 80-100th clearance but the pistons are hitting. I compared the EAB heads that are hitting with a nasty set of 8BA heads I had burried in the garage. The piston dome area of these heads is larger in diameter and significantly deeper (by 80-100th at high spot). My theory is that these heads have been milled over the years and now the dome is too shallow. Only currious thing is how much valve clearance I still have if the were milled?!? Is it possible for a machine shop to match the dome of my 8BA heads to the EAB? Is it worth it? How much matterial is in the piston dome area as this takes the heat and pressure from the combustion? Thanks, Josh
Dome should be about same diameter as the ones in your old 8BA heads...dome size is a good way to spot milling. Redoming requires shop to have or make a cutter matching piston dome. I do not know what milling limit is in terms of strength, but most millings of stock heads deep enough to do anything require redoming. Dome needs to be a pretty close match between head and piston, not just clearanced so it doesn't hit, for optimum performance...as with an SBC, close quench area fit is necessary or lots of things get worse. Remember that some recent pistons have a funny cone shaped dome...these will hit in the middle, leaving excess clearance at edge!. If your stuff is shaped about right your pistons should be hitting out where the dome is gone in head, not in center. Valve pockets are pretty deep on stock heads. One step at a time thinking out solution...or one for you, one for machine shop! Take your heads and one 8BA head to shop, see if they think they can redome to stock shape. Take your other 8BA head and do multiple foil ball checks at piston on your engine with gasket. How much clearance?? How much milling possible to get than down to 040?? Also, another set of EAB's should not be terribly expensive.
I would agree with Bruce. Check on over at Fordbarn.com. I'm sure someone there has a set of unmilled EAB's for less than $100. Just so you know, EAB's are the hot set-up if you are going to use stock 8BA heads so they may command more $$ than 8BA which are generally used for door stops, swap meet tent anchors and the such. Unless you plan to put a blower on top someday than stick with the 8BA's. Good luck and as 'Ol Ron says "Keep 'um runnin'!"
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