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Working It All Out: Discovering Y-Block Ford Tricks
By Doc Frohmader
The Y-Block Ford is the successor to the flathead and Henry’s first OHV V-8 engine. They were built from 1954-’64 and installed in Fords, Mercurys, Edsels and Ford trucks. They came as 239, 254, 272, 292, and 312s. All along there were just enough cracked heads to become a nuisance, and efforts were made to correct the problem.
The first was to alter the head itself. Ford began "posting" the Y-Block heads in 1957. A small ‘post’ of cast iron was included, supporting the combustion chamber from inside the coolant passages. If you reach inside the right coolant port you can feel it in there (don’t get your finger caught). Also, the date code on the head (1957 and forward) should identify them. Posting worked to some degree.
Most people thought the problem was isolated to the 312-cube T-Bird engines – especially the supercharged version – but it wasn’t. While the supercharged engines certainly had problems non-huffed engines suffer from less often, it wasn’t the increased temperatures or combustion chamber pressure that were the main culprits. That stuff just made the problem more obvious. Besides, the more expensive and exotic the car, the longer it hangs around and the longer you have to experience problems, so there was more opportunity for the 312s to go south.
So the second approach may appear obvious. Take a look at Y-block heads and you’ll see the two center cylinders have exhaust ports side-by-side. This creates a lot of heat focused between the two ports. Typically this requires extra accommodation for cooling, but Ford didn’t catch on to this until the end of the engine run. On most Y-blocks, you’ll find the passage in the head between the offending ports to be nearly clogged with rust and scale – making the problem even worse.
The solution is to drill two holes in the head and two more in the block. Fel-Pro includes this information in their head gasket sets and complete sets, but I still see a lot of these engines built without the modification. It’s simple enough – just locate the head gasket on the head or block, mark the centers for the missing holes where the gasket is punched for them, and drill the right sized holes. I also suggest you dig around and knock any rust and scale out of the cooling passage/water jacket in the head which may have filled over time. This really helps eliminate the problem.
Next up is the matter of Y-block rear main seals. For all but the 312, there’s been a Neoprene lip seal available and included in most gasket sets. For these engines, rear main leaks have been a non-issue. The 312 blocks were different because the main bore was machined larger. So up until recently the only seal available that would last at all was the rope-type seal. These are designed to seep a bit. If they don’t, they lack lubrication and they tend to burn up and then they really leak. A few attempts to use 318 MOPAR seals resulted in a similar problem. The MOPAR seals are just a little too tight when modified to fit, and the friction typically melts the seal.
The solution was developed by a smaller specialty gasket manufacturer called Best Gasket, Whittier, CA. They have recently contracted a seal maker to produce a purpose-designed lip seal for the 312. It has been lab and field-tested and the word is it works just fine. It is available through Best’s wholesale outlets or you can call them and they’ll direct you.
Third is a problem at teardown that can cause you fits – getting the distributor out. You’ll swear there is some mechanical means, other than the obvious hold-down, that is preventing you from moving or removing the distributor. The problem is the distributor housing and block were machined a bit tight and over time electrolysis causes the two to corrode and create a really tight connection. I see a lot of broken distributor housings.
If you start beating on things, you risk immediate damage. Also, beating on the housing doesn’t often work. So, first, you can heat the area up with a torch. You don’t want to get anywhere near glowing or melting, you just want it good and hot. There are commercial crust-busters that often work, but I’ve found that heating the area properly and then applying paraffin wax works well. You may want to do this several times. Also, light tapping can help loosen things. If you can get enough of the paraffin down along the housing (the wax wicks into the corrosion), the housing should break free.
Even when you get the housing to turn, you are not home free. Slowly work the housing until you can easily rotate it in the block. Don’t try to lift the distributor up until you can rotate it quite a bit. Then, lift as far as you can by hand, rotating the housing side-to-side and adding more lubricant as you go. The idea is to work it out slowly, not try to jerk it or beat it out.
I suggest you let the customer know about this and then handle it one of three ways. The most obvious choice is to tell them how to do it and let them spend their time on getting it apart, or tell them you’ll be charging them whatever time it takes to get it out. But there is a third option. These distributors are still common parts and readily available as rebuilts. You may want to just knock the old one out, regardless of damage, and replace it. Also, when you reassemble, coat the distributor housing with anti-seize and the problem won’t recur.
Another Y-Block quirk has to do with the oil filter. The engines built later in the production cycle went to a spin-on, but the blocks are all cast and machined the same. Of course, what this means is there’s an adapter used. Unless your customer is planning a concours-type restoration, the spin-on oil filter is obviously the best deal, so you’ll want to use the spin-on oil filter adapter.
At first glance, it looks like a no-brainer, but that’s where some get into trouble. Years of unfortunate and messy experience have taught me to approach the subject with a specific (and proven) procedure. First, there is a flat impregnated paper gasket that seals between the block and the adapter plate. Never, ever, not even once or a little bit, should you use any kind of sealer or gasket material here. If you do it will almost certainly end up with the gasket pushed out and all the oil on the ground. Put it in dry.
Second, the plate has to be installed in only one way. Look closely and you’ll see where it is stamped "TOP." This faces outward (I guess you could say that it is also the top), but the TOP script should also be at 12 o’clock or top as well. If not, the filter will drain dry in a very short time every time you shut the engine off. Obviously, you want oil to stay in the filter so you don’t start without oil – it’s hard on an engine.
Finally, the special threaded fitting that holds the plate on and allows the filter to spin on requires a 1-1/4˝ socket and about 50 ft.lbs. of torque. The problem is that a good many of the sockets available are too thick and you won’t get a good grip. I finally broke down and bought a cheap 12-point socket and ground the outside edge until I could get a good grip on it. The first time I dealt with this I invented quite a few new four-letter words before I realized what was needed. My advice: fix yourself up with that socket when you tear it down.
Speaking of tear-down, I’ve seen where people have chosen to leave the filter adapter plate on, tank the block and call it all good. This is also a recipe for trouble. Not only is that gasket likely to fail at some point, but you can never get the sludge and grit that inevitably builds up behind the plate cleaned out unless you remove it. Of course, I probably didn’t need to tell you that. I’m told only the highest quality, conscientious engine builders read this magazine...
this is a well written article on the Y Block. I would like to know, where no 1 cylinder is located, and and how the rest of the cylinders run to no 8, or right bank has certain nos Left bank has other nos Regards Daryl
by: ruj 1786 6/11/2009