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-   -   Ironhead Valve seats PICTURES (http://xlforum.net/forums/showthread.php?t=2079844)

Jaime1840 22nd July 2021 22:16

Valve seats PICTURES
 
Hello again guys,

It seems like I have face a new challenge everyday :laugh
This time it's the valve seats, I took the heads to a shop to get new guides installed, cut new seats. I did a leak test putting some gas in the combustion chamber to see if it would trough the valve and the seat and it did in one head. I took the heads apart I found the seats like you see in the pictures, what do you guys think? Did they actually cut new seats or just did some lapping?

PICTURES:

https://postimg.cc/gallery/9QLnwV1

perfesser 22nd July 2021 23:45

i don't see newly cut valve seats. i see filthy ports and old seats and what looks like new guides hammered in. do the faces of the valves you removed show evidence of being ground to fit new seats?

randy3934 22nd July 2021 23:48

looks like a poor lap job to me, I see pitting in the seat areas, if they were cut they would be gone.

ericfreeman 23rd July 2021 00:48

You need to check the valve protrusion to make sure they're not sitting too far down in the seats. Every time the valves and seats are cut the valve stems stick further into the rocker boxes. There's a factory spec that if exceeded, means you need to have hardened seats installed and cut.

Jaime1840 23rd July 2021 12:03

Quote:

Originally Posted by perfesser (Post 5906645)
i don't see newly cut valve seats. i see filthy ports and old seats and what looks like new guides hammered in. do the faces of the valves you removed show evidence of being ground to fit new seats?

hey, I was talking with a couple engine builders and they say the valve seats have been cut, but the job itīs not very good. the valves look fine I cant really tell if they have worked on the valves because the sitting surface has the lapping finish.

Jaime1840 23rd July 2021 12:06

Quote:

Originally Posted by randy3934 (Post 5906647)
looks like a poor lap job to me, I see pitting in the seat areas, if they were cut they would be gone.

Apparently when you cut seats you cut with 2 or 3 angles. It seems like they only have cut once and they didnīt do it properly. Im wondering if could just lap them my self and finish the job so they seat properly, I donīt really want to go back to that shop.

Jaime1840 23rd July 2021 12:07

Quote:

Originally Posted by ericfreeman (Post 5906670)
You need to check the valve protrusion to make sure they're not sitting too far down in the seats. Every time the valves and seats are cut the valve stems stick further into the rocker boxes. There's a factory spec that if exceeded, means you need to have hardened seats installed and cut.

I will, thanks.

bustert 23rd July 2021 13:06

sometimes with cast iron heads, you will get crappy cuts. if i were to redo cast iron heads, i would install harden seats which i have in my 74ch.
can you lap it in, why sure, but for how long will it seal, hummm, a good ?
have you tried popping the valve with a rubber mallet and see it the leak is still there?
if you pull the valve, coat the surfaces with some machinist ink and install without spring and twist to see where the two seat and how wide.
these heads are iffy at best so installed height is important as it shrouds the port. you have to be careful but you can port these a little. exhaust side more important than intake.

Jaime1840 23rd July 2021 13:20

Quote:

Originally Posted by bustert (Post 5906797)
sometimes with cast iron heads, you will get crappy cuts. if i were to redo cast iron heads, i would install harden seats which i have in my 74ch.
can you lap it in, why sure, but for how long will it seal, hummm, a good ?
have you tried popping the valve with a rubber mallet and see it the leak is still there?
if you pull the valve, coat the surfaces with some machinist ink and install without spring and twist to see where the two seat and how wide.
these heads are iffy at best so installed height is important as it shrouds the port. you have to be careful but you can port these a little. exhaust side more important than intake.

Hey,

I donīt really want to spend more money in the heads unless itīs absolutely necesary... I was thinking on taking them back to the shop or lapping them. I havent tried the rubber mallet method and I donīt have any layout dye but I guess I can get some.

perfesser 23rd July 2021 13:58

looking closer at the second photo, there are chatter marks and a discoloration on the intake valve seating surface that i would expect to be absent if they were cut properly. or at all. i would not be happy paying for someone to not do this work properly and call it done. maybe find another machinist to do a proper three angle job.


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