Update on 62 340 build. Bad news. Can this head be saved. PIC

[Bill O.]

Well, everything was going too well I guess. Builder found two not so good exhaust seats so had to cut new. The head already had been milled and had hardened seats. Hit water on this exhaust. I am sick about it as it is my original "X" head. Wondering if this can be saved and used. I have been reading up on the spray and furnace welding. Found an outfit in FL, Southeast Cylinder heads I believe off the top of my head that is awaiting pics to let me know what they think. Any thoughts? Thanks,

Bill Van Orman

[Mike M.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

i had a similar experience with a machine shop that attempted to add case hardened seats and hit anti-freeze. i'm told the casting are too thin to add inserts. mike

[Mike E.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

That's too bad...Damn..Was the casting changed in the '461' non X head so it can accommodate 2.02 valves?

It would seem like there would have been a problem because they are so close.


Mike

[Tom P.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

I'VE SAID THIS A THOUSAND TIMES ON SEVERAL OF THE FORUMS---------------------------------DO NOT, DO NOT, DO NOT, DO NOT, DO NOT HAVE HARD SEATS INSTALLED IN YOUR HEADS!!!!!!!!!!!!!!!!!!
Now you know why!!!!!!!!!! I have no sympathy!
After 40+yrs of experience with unleaded gas in these early/classic cars that do not have hardened seate, there just IS NOT enough evidence to justify having them installed. And, when having hard seats installed in early heads, the above picture is a PERFECT example of what can happen, thus the head becomes junk.
To specifically answer your question, it is VERY UNLIKELY that the head can be saved.
MANY machine shops will advocate having hard exhaust seats installed, because this is extra money for them--------------------but the benefits just ARE NOT worth it!!!!!
MANY, MANY people with older classic/performance/street cars that are not subjected to constant, long duration, heaving loads on the engines, have reported none or insignificant wear to the seats/valve guides. AND, for those engines that have a great deal of wear to the valve guides, the guides can easily be replaced---------------------------but installing hard seats-----------------well, you see what can happen.
Oh ya, one more thing--------------guess what happens when one of those seats comes loose when the engine is running-------------------you don't want to know.
Sorry, I've told too many people, too many times------------DO NOT HAVE HARD SEATS INSTALLED IN YOUR EARLY HEADS. Again, I have NO sympathy-----------------leason learned-----------------the hard way!

[Domenic T.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

Bill,
I agree with Tom about not needing hard seats, but I don't think the game is over.
I have used inserts to remove cracks and seal a bad seat. I know it sounds bad but they also sleeve cylinders to seal a crack to the water jacket.
If that seat is installed correctly with the right fit it will stay in place and seal the water jacket.
My 427 has a sleeve in # 4 because I found a crack in the cylinder.
I drove many years with a repair to the valve seat and had no problems, but if improperly installed they will wipe out a engine.
Aluminum expands at a different rate than steel and the steel seats stay in place when installed correctly, they are a must in aluminum heads.
Your cast head and the new seats should expand well together as they are of similar metal.

DOM


DOM

[Bill O.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

Tom, easy there big fella. Those caps make it seem like you are yelling at me lol. Not looking for sympathy, but the thing already had hardened seats from a rebuild done way before I got the car and apparently the seats were in rough shape, so I was told they needed cut. Not the end of the world. Just looking for a little help and ideas. I have had some feedback that this can be fixed and in a multitude of ways. Not sure what I am going to do yet, however. Thanks for the thoughts Dom.

Bill

[Joe M.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

Just a thought, on a set of heads with chipped bosses along the bottom I had a guy spray metal and remachine. I wonder if the same metal spraying process could be used on that valve seat???

[Joe L.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

Tom, easy there big fella. Those caps make it seem like you are yelling at me lol. Not looking for sympathy, but the thing already had hardened seats from a rebuild done way before I got the car and apparently the seats were in rough shape, so I was told they needed cut. Not the end of the world. Just looking for a little help and ideas. I have had some feedback that this can be fixed and in a multitude of ways. Not sure what I am going to do yet, however. Thanks for the thoughts Dom.

Bill

Bill------


In this particular case, I agree with Dom; I think the valve seat could be installed and would seal the breakout area. These inserts install with a very tight interference fit. Like Dom says, the exact same thing occurs with a "dry" cylinder sleeve and these usually seal just fine if properly fitted and installed.

However, I would probe the area adjoining the breakout area to make sure there is not a lot of very thin material there. If the breakout area were effectively enlarged (i.e. by extensive adjoining thin material), the valve seat insert will not hold. In that case, your best bet is to replace the head. It can't be that hard to find a suitable, correct replacement.

I also agree with Tom; don't install hardened valve seats as a matter of routine or, certainly, because you think they're necessary for use with unleaded gas. They are definitely NOT. However, in some cases seat inserts are necessary because the existing valve seat is damaged, badly worn or because the head has had too many valve jobs. In that case, one has nothing to lose (except money) by having the seats installed because the head is automatically junk without them.

[Terry D.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

Bill
Should you decide to replace the head, depending on the date needed I have one head left from a simular problem.
Terry

[Mike E.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

I had heard of parts being cooled in dry ice then press into the place to create an even tighter interference fit. Could a method such as that be used to install the seat? Perhaps that's the way they are installed normally, if so forgive my lack of machining knowledge.

I'll be having my heads gone through soon. I’ll remember this tread for sure if the shop suggests hardened seats.

Mike

[Bill O.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

Thanks for the thoughts guys. I sent the head off to have it evaluated and we will see what happens. Terry, I sent you a PM on your head. The casting date of both of my original heads is Sept. 11th, 61. How early of a date would work with my car #1243, with an engine assembly date of Oct. 4th?

[Mike E.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

Essentially any date prior to the assembly date stamped on your block.

[Bill O.]

Re: Update on 62 340 build. Bad news. Can this head be saved. PIC

Thanks Mike!