 Dropped a valve seat...what's the verdict? |
|
|
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
|
| billh1963 |
 Aug 15 2016, 04:29 PM
Post
#1
|
|
Car Hoarder!  Group: Members Posts: 3,408 Joined: 28-March 11 From: North Carolina Member No.: 12,871 Region Association: South East States  |
Way back in August 2013 I went to start my 914 and heard a funky noise. I immediately shut it down. Using my limited mechanical knowledge (and a tremendous amount of luck) I postulated that I had dropped a valve seat.
Three years later I decide it's time to get this 914 back on the road. Pulled the heads and, sure enough, a dropped valve seat. Prior to the issue the car was running good...no smoking, seemingly good oil pressure, etc. I'm hoping I can get by with just rebuilding the head (if possible). Anyone see anything that would cause me to deviate from this plan of action?   |
   |
 
|
  |
Replies
| HAM Inc |
Aug 15 2016, 06:43 PM
Post
#2
|
|
Senior Member Group: Members Posts: 847 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
The seat drop repair alone is not so bad, as far as consequences to the casting's integrity. But the crack out the exhaust port is a real killer for the T4. It can be repaired, (done it countless times over the past 20 years) but the casting will never be the same.
Time to stick a fork in that one. BTW, those cracks were really common on smog heads. Is your head one of them? Just curious. |
|
|
|
| ConeDodger |
Aug 15 2016, 07:47 PM
Post
#3
|
|
Apex killer! Group: Members Posts: 24,028 Joined: 31-December 04 From: Tahoe Area Member No.: 3,380 Region Association: Northern California 
|
QUOTE(HAM Inc @ Aug 15 2016, 08:43 PM)  The seat drop repair alone is not so bad, as far as consequences to the casting's integrity. But the crack out the exhaust port is a real killer for the T4. It can be repaired, (done it countless times over the past 20 years) but the casting will never be the same. Time to stick a fork in that one. BTW, those cracks were really common on smog heads. Is your head one of them? Just curious. Len is of course one of the few people you could trust with a repair of this sort. The problem is, it has become economically unfeasible to do this repair. The valve seats aren't a big deal as Len said. In fact they should be done on any rebuild of a Type IV head. Len puts the heads in an oven without valves in place and many of the seats fall out just due to the heat. The welding needed to repair the cracks, and if I can see three? There are at least a couple more is the killer. It becomes pretty quickly cheaper to just buy a set of the LE200 heads and cook yourself up a 2056 or 2270. Sorry... |
|
|
|
| HAM Inc |
Aug 16 2016, 09:29 AM
Post
#4
|
|
Senior Member Group: Members Posts: 847 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
QUOTE(ConeDodger @ Aug 15 2016, 06:47 PM) QUOTE(HAM Inc @ Aug 15 2016, 08:43 PM) The seat drop repair alone is not so bad, as far as consequences to the casting's integrity. But the crack out the exhaust port is a real killer for the T4. It can be repaired, (done it countless times over the past 20 years) but the casting will never be the same. Time to stick a fork in that one. BTW, those cracks were really common on smog heads. Is your head one of them? Just curious. Len is of course one of the few people you could trust with a repair of this sort. The problem is, it has become economically unfeasible to do this repair. The valve seats aren't a big deal as Len said. In fact they should be done on any rebuild of a Type IV head. Len puts the heads in an oven without valves in place and many of the seats fall out just due to the heat. The welding needed to repair the cracks, and if I can see three? There are at least a couple more is the killer. It becomes pretty quickly cheaper to just buy a set of the LE200 heads and cook yourself up a 2056 or 2270. Sorry... Thanks for the plug Rob. How's your ride doing these days? Still good, I hope. The LE200's would be too much head for a typical street 2056. The RS+ heads would be a better fit, unless peak power is what you're after, like for a track car. |
|
|
|
Posts in this topic
billh1963 Dropped a valve seat...what's the verdict? Aug 15 2016, 04:29 PM
Mike D. I did the same thing back in 2000. Had the head re... Aug 15 2016, 04:36 PM ConeDodger I see at least two and maybe three cracks in that ... Aug 15 2016, 04:46 PM
billh1963
I see at least two and maybe three cracks in that... Aug 15 2016, 04:54 PM
porschetub
I see at least two and maybe three cracks in that... Aug 15 2016, 05:05 PM porschetub Oh dear the head is scrap ,not worth the repair co... Aug 15 2016, 05:01 PM billh1963
Oh dear the head is scrap ,not worth the repair c... Aug 15 2016, 05:08 PM r_towle Depending upon your finances I would suggest you b... Aug 15 2016, 06:04 PM 76-914 Is that piston cracked above the indentation? Aug 15 2016, 06:13 PM billh1963
Is that piston cracked above the indentation?
I... Aug 15 2016, 06:27 PM billh1963
The seat drop repair alone is not so bad, as far ... Aug 15 2016, 06:45 PM Philip W. Looks like you will be building that 2056 --- you ... Aug 15 2016, 08:08 PM Toast I've had a valve seat embedded in a head befor... Aug 15 2016, 11:40 PM cwpeden And don't use head gaskets. I used them for th... Aug 16 2016, 12:40 AM |
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 9th May 2025 - 01:40 PM |
Invision Power Board
v9.1.4 © 2025 IPS, Inc.