Cracked seats

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rocketracer380
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Cracked seats

Post by rocketracer380 »

034 bow tie heads cracked seats. Can this be repaired
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ProPower engines
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Re: Cracked seats

Post by ProPower engines »

Best I can say is maybe.
You will have to cut for a new seat to be pressed in and check for cracks after the pocket is cut.
Sometimes they are not deep enough to hit water other times they are. Cut for a seat then mag and pressure test to confirm otherwise scrap it and get a replacement.
Someone may say weld it but that rarely works unless the complete head is oven heated then welded in the oven.
Then a slow 24hr cool down to resist cracking.
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KnightEngines
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Re: Cracked seats

Post by KnightEngines »

Yes, stitching pins & a seat insert.
But is it worth it?
rocketracer380
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Re: Cracked seats

Post by rocketracer380 »

average cost for stitch pin repair
KnightEngines
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Re: Cracked seats

Post by KnightEngines »

rocketracer380 wrote: Mon Nov 02, 2020 11:20 pm average cost for stitch pin repair
Over there I don't know, I charge $15 1st pin, $10 a pin after that, minimum charge $55 or it's more of a fcuk around than it's worth.
Seat insert is $45 plus cost of insert, then you need a valve job.
Pressure test after to make sure it's good.
So about $380 to fix & do a performance valve job.
That's without bead blasting, guide work (k-lines or whatever is needed), refacing valves, setting tip heights, milling the faces, washing & assembly etc.

The heads would want to be worth saving.....
PRH
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Re: Cracked seats

Post by PRH »

On the other hand........

Depending on what it’s being used on........ if it pressure tests good as is........ you could just keep running it.
Somewhat handy with a die grinder.
Charliesauto
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Re: Cracked seats

Post by Charliesauto »

rocketracer380 wrote: Mon Nov 02, 2020 4:36 pm 034 bow tie heads cracked seats. Can this be repaired
You need to have it cleaned and magnafluxed to determine the extent of the crack. Based on what I see in the photo, you can likely install a seat. I have put hundreds of seats in the 034 bowtie's and never an issue with water. Typically used 1.680" OD and counterbored .250" - .280" deep.
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