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Bum Dealio... Just pulled the heads off my motor and found a couple valve seats came out and one was smashed into pieces. Who out there can work some magic and repair the combustion chambers and redo all the valve seats on alum heads? And that is "if" its even repairable, its pretty hammered but I bet can be welded and fixed.

Why might something like this happen? Intake valve on #2 and Exhaust valve on #1. Injected Alky Blower motor, dry (no coolent/water). Is there any keys to them both being in the front? Like maybe something got a little to lean or hot? Is it the front or back of the blower that tends to run leaner? The plugs all looked the same... with no heat distortion.
 

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steelcomp was here
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Bum Dealio... Just pulled the heads off my motor and found a couple valve seats came out and one was smashed into pieces. Who out there can work some magic and repair the combustion chambers and redo all the valve seats on alum heads? And that is "if" its even repairable, its pretty hammered but I bet can be welded and fixed.

Why might something like this happen? Intake valve on #2 and Exhaust valve on #1. Injected Alky Blower motor, dry (no coolent/water). Is there any keys to them both being in the front? Like maybe something got a little to lean or hot? Is it the front or back of the blower that tends to run leaner? The plugs all looked the same... with no heat distortion.
Bill, send me some pics...I can fix em.
[email protected]
 

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Any real shop should be able to fix them. It can be welded.
Lean.... what did the plugs look like? Before they were busted up. LOL
Were the heads new or used when you got them. It is very rare to drop a seat in a head (if it was installed properly...meaning proper press fit.)
Maybe someone sold you junk?
Wags

Need more info.
 

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Discussion Starter #4
Actually the plugs were not damaged at all... but don't ask me how all that stuff missed it. Based on reading the plugs I think the motor is way rich.

I thought it was pretty wired to drop not one but two seats. It is true I know nothing about the heads or motor for that mater as I just got it not long ago and this is the first time to open it up. Everything else so far (Including the multi-peice push rods with one of the end broken off) has been questionable so I am not surprised if maybe the seats/bores were not sized correctly.
 

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steelcomp was here
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Once one seat starts to go and breaks into pieces, it's not uncommon for the other to get beat out, especially if they're interlocking. Valve springs might have gone away and/or over rev-valve float. This can beat the crap outa things. Did you break a valve? How hard were the retainers to get off?
Seats usually don't just fall out, but if it was a bad repair, they could after some abuse. Blown alky engines can be hard on valve train.

ETA: just re-read...two seats in different chambers. Probably pieces of the broken ex seat cross flowing in the intake. If the seats are valve jobbed a bunch of times they can get thin, too, and it doesn't take much to loosen one.
 

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Discussion Starter #6
That just reminded me of something. The tranny failed to shift on its own so I was on the 8K rev limiter for a couple of seconds before I got it shifted. Plus the guy I got this thing from never backed the valves off in the winter so who knows if the springs are any good or not.

I have not disassembled any of the valve train yet so I will report back as to how hard the keepers are to remove. I will also get some pictures coming.
 

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Discussion Starter #7




Looking at the second head with the ex seat coming out looks like it has some porosity on the bottom of the chamber like it has been fixed once already.
 

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Looking at the second head with the ex seat coming out looks like it has some porosity on the bottom of the chamber like it has been fixed once already.
Yep.

A porous weld will not maintain the press fit required for the seat in a HP application.

Also, if the seat insert is not carefully chamfered, and set square in the bore top before the initial "blow" to insert it, it will peel a small sliver of Alum. in the bore, which then seats itself under the insert.
I used to repair a lot of different Alum. heads, and this was something I saw frequently in heads that had been repaired before.
Get them cleaned up and blasted. Make sure to blast them under the seat area completely. If they had seats incorrectly installed at some time, you will be able to see a little gap under the inserts. Plus, the valve job will look crooked on the insert, with no consistency from seat to seat.
Take a valve and check valve tip heights using the same valve.

May have to have all the seats replaced, or at least the ones in any repaired chamber.
Good luck!
 

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Bum Dealio... Just pulled the heads off my motor and found a couple valve seats came out and one was smashed into pieces. Who out there can work some magic and repair the combustion chambers and redo all the valve seats on alum heads? And that is "if" its even repairable, its pretty hammered but I bet can be welded and fixed.

Why might something like this happen? Intake valve on #2 and Exhaust valve on #1. Injected Alky Blower motor, dry (no coolent/water). Is there any keys to them both being in the front? Like maybe something got a little to lean or hot? Is it the front or back of the blower that tends to run leaner? The plugs all looked the same... with no heat distortion.
I would recommend Greg Jacobson out of Riverside I believe. Had a crack in #6 exhaust port that ran in behind the seat. Sent my Pontiac's to him and he did a beautiful job repairing them. Installed height was dead nuts and you can't even tell he welded them. We've also sent in a couple heads for repair that a customer had kicked a rod and caused some serious damage. Once again beautiful work. I guarantee you won't be disappointed!!!!
 

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steelcomp was here
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Those are fine. I've repired heads that you couldn't tell what you were looking at..these are basic. It does look as if they have been repaired, but it's hard to see in a picture.
BIll, I'd be glad to help you on these but due to shipping you may want to try and find someone local. Just make sure they know what they're doing. There's more to it thanjust welding up the dmage and installing new seats.
 

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since the heads have been welded on before you should have them checked for being soft from weld overheat, some can be re-heat treated and some not, if you have a set of soft heads they wont hold seats for long.

you might send them over to brodix or reher-morrision
 

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since the heads have been welded on before you should have them checked for being soft from weld overheat, some can be re-heat treated and some not, if you have a set of soft heads they wont hold seats for long.

you might send them over to brodix or reher-morrision
DONT send them to brodix, ( nothing personal to you Sir ) , I need to learn to post pic to show you what brodix did to a set of head's of mine ,,( a first grader could have welded them better ) ,, they welded on them twice then told me they were unrepairable ,, :|err...........Eric
 

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Eric, did you ever get them fixed after that. I would be willing to bet either Steelcomp or Walt Ott could still repair them. I know Walt has repaired some pretty broke up sh-t and they were just fine.
This is not basic stuff but the guys who know it can just about work miracles.
 

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I've been thru this before, may or may not have anything to do with your heads. i bought a very used set of aluminum heads, 1st gen of chevy aluminum heads, before D ports, had a little damage in the combustion chambers, no big deal. They ran good, no problems for a while, then I dropped a seat. Repaired the damage,everything is good for a while. I dropped another seat,WTF, took them to Moritz, (before Ron) they said aluminum heads after many heat cycles will lose their strengh, they saw this a lot in round track cars. They said it would cost more to reheat treat my heads than they were worth. Hope this helps and sorry it is so long.
 

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Eric, did you ever get them fixed after that. I would be willing to bet either Steelcomp or Walt Ott could still repair them. I know Walt has repaired some pretty broke up sh-t and they were just fine.
This is not basic stuff but the guys who know it can just about work miracles.
THANK'S
I pm'ed Steel about them , they are sitting on the shelf right now , thought I had a use for them but fell through,, they will collect some more dust for a lil while longer :mad:,, lol,, ...........Eric:)hand
 
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