valve seats

[ole39]

managed to get 8 intake valve seats out with my mig. used the mig on the exhaust seats, wont budge, tried flux core, same thing. starting to wonder if there are any seats there. i know the later engines done away with valve seats, but never hear of mixing them. any ideas?

[tubman]

I believe there may have been engines with exhaust seats but no intake seats during the 8BA era, but I don't think the other way around would make sense. I could be wrong, but I seem to remember reading it somewhere.

I'd take a good hard look at the exhaust seats to see if they are in the block if it's an 8BA.

[Ol' Ron]

True exhaust and intakes had seats in 48 and part of 49. then they dropped the intakes. till the end of 51. after that no seats.

Hope I got the dates right, memory not so good any mpre.
Gramps

[tubman]

Actually, I think the transition occurred a little bit later (the '51 model year).

[1952henry]

My 8RT from a 52 appears to have exhaust seats. Can’t be positive, but sure looks like it.

[Bored&Stroked]

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You should be able to clean up around an exhaust seat and determine whether it has a hard seat or not. I've never seen a block with hard seats in the intakes and not in the exhausts, but EVERYTHING is possible with flatheads . . . it has all been done by somebody in the past! LOL

[marko39]

My 51 block doesn’t have hardened seats.

[ole39]

1st, i would like to correct my info. it is the exhaust seats that came out easy, not the intakes. 2nd i am certain the intakes have no seats. as much work i have put into them and not even a budge. called my local machine shop and they are backed up for 2 months! guess i am done for now. flatheads, gotta love em.

[Tim Ayers]

Originally Posted by 1952henry

My 8RT from a 52 appears to have exhaust seats. Can’t be positive, but sure looks like it.

I believe trucks kept them and cars started to phase them out. I believe in '53 they phased them out all together (at least on the car blocks).

[big job]

Maybe try a little witness mark with a sharp punch if you can its the block. Reply's are correct. But then model t s seats are machined in the block. My model t has intake & exhaust hardened seats (( because I put them there lol .....(original were so bad)

[tubman]

Originally Posted by ole39

1st, i would like to correct my info. it is the exhaust seats that came out easy, not the intakes. 2nd i am certain the intakes have no seats. as much work i have put into them and not even a budge. called my local machine shop and they are backed up for 2 months! guess i am done for now. flatheads, gotta love em.

Now this whole thing makes sense. I did a little checking, and during the transition to rotating valves, the seats were eliminated (on the automobiles). First the intakes, then the exhausts. (The rotating valves supposedly made the hard seats unnecessary.)

Now all you have to do is figure out if you want to install exhaust seats during the rebuild. You probably will want to.

[Bored&Stroked]

My guess is that now that you've welded on the intake seats, you'll probably need to have them put in hard seats, and/or increase the intake valve sizes so you get to "good material" to grind a seat on. There are lots of options to work from.

[Ol' Ron]

I like to use the rotators on a "street " engine. They work well on cams up to350" lift. It's alittle tricky on the long valves.
Gramps