replacing valve seat in situ

Thanks for all the help.
i'm going to take out the lifters and try the 7 cylinder option until it drives me nuts and i pull the engine
 
A friend here on the island threw a rod on his 6 cyl flathead dodge 4 door when he was in high school. He and his dad pulled the pan and removed the piston and rod and Frank drove the last year and a half to school on 5. Said he just had to downshift sooner on the hills.
 
I had a good look at the seat and saw it had cracked.I cleaned it up,cleaned where it seats,put JB weld on the back and outside of the seat.
I then turned it on the crank and positioned it by letting the valve press down on it.
I then used my punches to tap it into place and peened it slightly over. I then filled all around the seat with more jb weld,put the head back on and have 70lpsi of compression.Can't say how long it will last but here's hoping


 
Please let us know how this turns out. It could be a disaster, but I have seen crazier things work in these old flatheads. I once honed and re-ringed an 8BA that had 7 visible cracks between the cylinders and valves, and ran it for another couple of years before my dad had it junked because of rust on the body. (I was all of 19 then.)
 
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in theory it should work
the resin has a higher melting point than the engine reaches.The seat is peened over and i'm not doing 10 second quarters in it.No reason why it won't work out
At worse i'll be back where i started and a couple of hours of my time wasted
At best i've had a lot of help from you guys and enjoyed doing it
 
DjNeil said:
in theory it should work
the resin has a higher melting point than the engine reaches.The seat is peened over and i'm not doing 10 second quarters in it.No reason why it won't work out
At worse i'll be back where i started and a couple of hours of my time wasted
At best i've had a lot of help from you guys and enjoyed doing it
Click to expand...

Hi "Dj", just curious, but what temps are you expecting to be experiencing with respect to the resin??

Sure would be nice to see it work though, really. Good luck.

Thanks, Gary in N.Y.

P.S. The temps that both the seat and valve are going to be "feeling" may be around 1200 degrees, give-or-take a few!
 
It is an exhaust valve, which ain't good; I'd give this a better chance of working on an intake. Hope it works out for you!
 
You will probally need dry ice to bring temp down ,try you local fire extinguisher guy for dry ice
 
if you pull the lifters there won't be much heat there---if you try to run it on that cyl it most likely will come apart in a few miles

I once "fixed" a 6cyl jeep engine that broke a piston and the wristpin ate through the wall---turned a pine plug to fit the cyl and glued it in, put tin and exhaust clamp over the oil hole in the crank---it plowed driveways for years that way till the frame broke
 
I'm hoping he did a good job with the punches, piling up a lot of metal against the seat.... I have fixed external water jacket cracks with marine tex and jb weld, but never considered it inside the combustion chamber. x2 on intakes because they draw in cool air.
 
I think the jb weld will be just along for the ride and will probably just burn away. the staking of the seat in place will probably hold the seat in place, but if the seat wasn't replaced with a good one, who knows how long that will last.

The engine will run and probably run ok for quite a while. Even if that cylinder was only 90% as good as the others, if the others are at 100% the engine will be running 98.75% as good as it would be if they were all good.

A bit of ******** there by quoting numbers, I know, but you might get what I am trying to say. It will probably be ok, for a while at least, and it may never be driven long enough for it to become an issue again.

Mart.
 
You put the cracked seat back in with JB Weld? I fear this will not go well......

Just FYI, I've seen a few engines badly damaged by chewed up and spit out valve seats.

I could see putting a new seat in, and potentially trying to seal it with something (JB Weld, Loc-tite, or other good sealant), but I can't see reusing that old seat.
 
That stuff sounds very interesting; I'm filing this away for future use. For $29.95 for 2 ounces, it better be good!
 
Hey when you are as old as us what else can u get for 29.95.
My rum is 50.00 a bottle but well worth it. You should try the Rum.

diplomatica-reserva-eclusiva.jpg


R
 
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