Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > Porsche 911 Technical Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Jan 2015
Posts: 24
79 head stud repair

Have a 79sc and just found out #6 head stud is broken.
Car has only 48,000 miles. Do I do head stud repair only, top end or complete rebuild.
My thinking is top end. Car seems to run fine but would like to keep it going forward.
IS 40 yearss old with no previous engine work.
What should a top end cost compared to complete? Original stock car. Thanks for any input.

Old 05-22-2019, 07:07 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered User
 
jamesjedi's Avatar
 
Join Date: Aug 2004
Location: The Brink
Posts: 2,798
There are many threads on this. Top end only - is of course cheaper. The thought is that you are most of the way there for the bottom end. 48,000 may not have bottom end issues, but it may leak after 40 years.
Old 05-22-2019, 07:53 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Under the radar
 
Trackrash's Avatar
 
Join Date: May 2007
Location: Sebastopol, the land of wine and redwoods in The Republic of California.
Posts: 6,671
Garage
You might want to tell us your location. And how much, if any, work you plan on doing yourself. Prices have been quoted from ~$4k to $20k for a shop to do all the work.

Search here and in the 911 Engine Rebuilding Forum and you will find lots of info.
__________________
Gordon
___________________________________
'71 911 Coupe 3,0L outlawed
#56 PCA Redwood Region, GGR, NASA, Speed SF
Trackrash's Garage :: My Garage
Old 05-22-2019, 08:39 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered
 
john walker's workshop's Avatar
 
Join Date: Mar 2001
Location: Marysville Wa.
Posts: 18,934
Being that it needs to come down for stud replacement, disassemble all the heads and see how the guides feel. That top end job will reseal from the case outward. Do the case halves seep enough to worry about?
__________________
https://www.instagram.com/johnwalker8704

8009 103rd pl ne Marysville Wa 98270
206 637 4071
Old 05-22-2019, 09:08 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered User
 
Join Date: Jan 2015
Posts: 24
Thanks I'll check out other threads. , I am in central Virginia. Will not being doing any work myself.
Car seems very dry on bottom and uses very little oil.
Never see any drips when parked.
Old 05-22-2019, 09:19 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Registered
 
fred cook's Avatar
 
Join Date: May 2001
Location: Deep South
Posts: 4,915
Garage
Rather than just replacing the one broken stud (probably one of the bottom Dilivar studs), replace all of the bottom studs with steel ones. The Dilivar studs can be identified with a magnet as they are not magnetic. Broken Dilivar studs on these engines is a common issue. I would have the heads done while they are off, replace the studs and fix any small leaks you find. The rest should be ok.
__________________
FEC3
1980 911SC coupe "Zeus" 3.3SS
god of thunder and lightning
Old 05-22-2019, 09:22 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Registered
 
Join Date: Jan 2008
Location: sunny buffalo
Posts: 610
Two years ago the broken head stud demons came into our '75 911S. $16.k later she runs well not including opening the case.

Sorry to hear of your misfortune.

Yes, many threads exist and if you are handy with a wrench give it a try yourself
Old 05-22-2019, 03:23 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Registered User
 
jamesjedi's Avatar
 
Join Date: Aug 2004
Location: The Brink
Posts: 2,798
The broken studs will be the lower diliver studs. Steel uppers would most like be fine. If you don’t have the budget to do a full rebuild - replace all studs with new steel studs and have the heads rebuilt. Replace the gaskets.

I would be curious if anyone has seen a broken steel stud? Perhaps race engines with high power?

Last edited by jamesjedi; 05-22-2019 at 04:59 PM..
Old 05-22-2019, 04:47 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Red Line Service
 
Marc Bixen's Avatar
 
Join Date: Jan 2010
Location: West Los Angeles, Ca. www.redlineservice.net
Posts: 564
Garage
Boy, you guys need to do some homework on studs. Sounds like your trying to make more work for the few good engine builders still around.
__________________
Marc Bixen
Red Line Service
West Los Angeles, Ca.
www.redlineservice.net
info@redlineservice.net
Old 05-22-2019, 04:58 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #9 (permalink)
Under the radar
 
Trackrash's Avatar
 
Join Date: May 2007
Location: Sebastopol, the land of wine and redwoods in The Republic of California.
Posts: 6,671
Garage
Quote:
Originally Posted by Marc Bixen View Post
Boy, you guys need to do some homework on studs. Sounds like your trying to make more work for the few good engine builders still around.
???

Are you offering your services? Give the OP a quote.

He stated he is not doing any work himself.

Perhaps there is a shop near him that will do the work for reasonable $. Perhaps someone will chime in about that.
__________________
Gordon
___________________________________
'71 911 Coupe 3,0L outlawed
#56 PCA Redwood Region, GGR, NASA, Speed SF
Trackrash's Garage :: My Garage
Old 05-22-2019, 05:25 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)
Registered User
 
otto_kretschmer's Avatar
 
Join Date: Jun 2010
Posts: 491
first thing I would do is a leak down on all cylinders

if the engine is tight, I would take one head apart and inspect the guides and valves

if the guides and valve on that one head (#6 since you gotta take it off anyway) are good I would just replace the studs and put the engine back together

its still going to be pricey since you are having someone else do it but that can't be helped

old cars are a gamble any way you look at them and if you want to keep everything like it just rolled out of the factory its going to have to be in the Jay Leno league
Old 05-22-2019, 06:19 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #11 (permalink)
Registered User
 
otto_kretschmer's Avatar
 
Join Date: Jun 2010
Posts: 491
one more bit

if a leak down for all cylinders are good, like 94 psi down stream and 100 psi upstream of the orifice, and you have good oil pressure then your engine is in good condition

Old 05-22-2019, 06:42 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #12 (permalink)
 
Registered
 
Join Date: Aug 2017
Location: Long Island
Posts: 599
Garage
I drove my '79 with 4 broken head studs for several years before having a top end rebuild ... yes, shameful of me ... drove about 1.5K miles/yr.

Total cost was about $16K (Long Island), but included SSI's, up-graded chain tensioners.



Jason
__________________
'79 911SC Targa
Old 05-23-2019, 05:02 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #13 (permalink)
Registered User
 
Join Date: Jan 2015
Posts: 24
Thanks for all the input.
I will probably drive it for a while longer.
Seems to drive fine ....at the moment.
Small monthly jaunts, nothing long.

Buying a new piggy bank today! haha

Old 05-23-2019, 07:25 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #14 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 08:22 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2020 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.