Hardened valve seats?

GreenMonster48

GreenMonster48

Well-known member
Are they really necessary on a Flathead? I've got a block at the machine shop now waiting on the verdict of whether or not it's a good unit, and the guy asked if I would be needing hardened valve seats installed. For the build it's going to be an 8BA, stock stroke, 3/4 cam, 4 barrel carb, and aluminum heads, very mild motor. I'm thinking I don't need them since the compression will only be around 8:1. Is that ok?
 
Hardened valve seats are used to control valve seat recession caused by the lack of lead in the gas. I would suggest that you have them installed.
 
If it were mine, I'd feel better with them in the exhausts. What year is your block? Anything pre-52 should already have them in the exhausts.
 
And...you might want to look to see if you already have them. Early 8BA type engines have 16, later ones vary apparently by original use. Trucks got hardened seats til the end of production, other engines had exhaust only or none. '52-3 passenger typically had none. Earlier engines from later '30's til 1948 had them.
The original Ford inserts are usually pretty good and can be kept with minimal refacing.
 
It's pretty much impossible to figgerout origin of an 8BA unless you bought it new yourself, but any seats will be easy to spot...and of course the crack inspection should also point out the seat seam, if any, to the shop.
I would not regard hard seats as a necessity but they are nice. The originals rarely need more than a quick touchup after many years of use.
If you have no seats, I think decision could be based on the condition of the "soft" seats...if they will save with only a light buzz from the grinder, great...if they are deeply pitted, which they are sometimes, installing seats is somewhere between preferable to sinking the seats with heavy grinding and mandatory.
 
You don't need hard intake seats, the cold gas going in keeps then cool. Most flatheads have hard exh seats from the factory, some of the late 8BA don't have hard seat, I'd recomend installing hard exh seat if your don't have them. Walt
 
If you plan on doing a fair amount of highway driving, I would definetly have hard seats in the exhaust.
 
NEARLY all 59A's have 16 hard seats, and others back into the thirties. I suspect that Ford cranked out 59's beyond 1948 to meet the parts demand, and tha the few 59's that turn up with no seats are post-production use engines. After 1948 the cost cutting squad known as the whiz kids progressively got rid of expensive details...
 
This is what I love about the Ford Flathead. 80 years later and we're still talking about them,finding things out about them, and debating on them. Not too many other things you can say that about! Thanks again all for your feedback
 
I have a block that has 99 in the center top water jack and on the front top at No1 cylinder. The block has the 4 freeze plug in the sump face 3 3/16 bore. Does this have harden seats as well. The block year must be around 1940-41 I think. The block it is in my 47 sedan. They must of made these cars to ship oversea from old stock. Even the dash is from a 41 but it has been classed here as a 1947 vehicle.
 
That Canadian engine would be from 1939-40. Likely a WWII produced engine that found its way into the replacement parts stream later. Unlikely it came in a '47...Canada changed over to a different block early in WWII! It should have hard seats. Not sure when hard seats became standard, maybe '36 or 7?
 
There is a note in the 38 - 39 Restoration Book that states hard seats were 100* as of Sept,1938. Hard seats were used on the exhausts back to 1935.
 
Thanks for info Bruce.
I often wonder if my vehicle is original. I have own it for 32 years. No changes my end.
Would it be common for these vehicle shipped overseas to have different year parts in them?
Have just purchased new valve system to convert to the 8ba type with adjustable lifters I purchased hard seats as well just in case.
 
All flatheads that I have seen from 32-48 had pop out seats, even Model B engines had pop out seats. The 8BA engine had just exh pop out seats, except the 8RT truck engine had all 16 pop out seats. Some of the 8BA style car blocks (I have seen this mostly in merc. blocks) did not have any pop out seats. Walt
 
The 52-3 blocks without hardened seats have valve rotators to help the valves. I do believe this is a good system, but recomend a hardened seat for the exhaust.
 
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