case bolt orientation
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- AndrewSlater
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case bolt orientation
Not wishing to admit to a possible 'f*** up' but does the orientation of the case bolts ( i.e. which side the acorn nut is on ) matter?
The Wayne Dempsey book that I have been following seems to show them on the opposite sides to the PET manual.
http://www.101projects.com/911-rebuild/ ... ge-147.htm
Is there any particular reason?
Also if when tightened one or two of the bolts show the o-ring to have broken out is it safe to rectify them one bolt at a time?
As always any advice much appreciated.
The Wayne Dempsey book that I have been following seems to show them on the opposite sides to the PET manual.
http://www.101projects.com/911-rebuild/ ... ge-147.htm
Is there any particular reason?
Also if when tightened one or two of the bolts show the o-ring to have broken out is it safe to rectify them one bolt at a time?
As always any advice much appreciated.
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
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911hillclimber
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Re: case bolt orientation
My last rebuild on my 3.2 followed the Dempsey book. As to the O rings rupturing out, try a smear of the case sealant to lubricate them. Nothing leaks on my engine.
If there is zero damage then re use, but look very closely. Critical they are all trapped in place or they will leak.
If there is zero damage then re use, but look very closely. Critical they are all trapped in place or they will leak.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
- AndrewSlater
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Re: case bolt orientation
I'm a bit surprised that Waynes book has the bolts on the opposite side to the PET guide.
Looking back at photos of other cases ( mine included ) they do generally appear to be as per the PET guide.
I followed Waynes advice of using the RTV, which may or may not help lubricate or seal the o-ring.
I think two or three are damaged in that I can see the o-ring has snapped.

It's strange as this is on bolt head side and my son was holding this side and trying to ensure it did not turn once fitted. I was wondering if it is because they are on the 'wrong' side of the case as I read somewhere that one side of the case may have bevelled holes. Some people suggest bevelling all the holes but I didn't do this.
I think the plan is to redo the through bolts one at a time.
Now I need to figure out where to get some new O-rings from.
The ones in my kit were blue, but some say the green Viton ones are better, the ones from RosePassion are shown as red/orange.
I might buy a few replacement bevelled washers as a least a couple of mine were slightly corroded and that won't make the o-ring sit in smoothly.
Anyone know where I can get a spare case bolt so I can prep one bolt first before removing one from the case?
Looking back at photos of other cases ( mine included ) they do generally appear to be as per the PET guide.
I followed Waynes advice of using the RTV, which may or may not help lubricate or seal the o-ring.
I think two or three are damaged in that I can see the o-ring has snapped.

It's strange as this is on bolt head side and my son was holding this side and trying to ensure it did not turn once fitted. I was wondering if it is because they are on the 'wrong' side of the case as I read somewhere that one side of the case may have bevelled holes. Some people suggest bevelling all the holes but I didn't do this.
I think the plan is to redo the through bolts one at a time.
Now I need to figure out where to get some new O-rings from.
The ones in my kit were blue, but some say the green Viton ones are better, the ones from RosePassion are shown as red/orange.
I might buy a few replacement bevelled washers as a least a couple of mine were slightly corroded and that won't make the o-ring sit in smoothly.
Anyone know where I can get a spare case bolt so I can prep one bolt first before removing one from the case?
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
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johnM
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Re: case bolt orientation
Yep Wayne doesn't know everything. He is a aircraft engineer by trade and wasn't trained by Porsche. PET is correct with regard to case bolt orientation.AndrewSlater wrote:I'm a bit surprised that Waynes book has the bolts on the opposite side to the PET guide.
Looking back at photos of other cases ( mine included ) they do generally appear to be as per the PET guide.
Speak to Mike Bainbridge he may have a spare bolt. 01539567959.
John
1970 2.2E Coupe.
2004 996 GT3 mkII
2015 Skoda Octavia VRS TSI DSG.
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1970 2.2E Coupe.
2004 996 GT3 mkII
2015 Skoda Octavia VRS TSI DSG.
2021 Toyota GR Yaris Circuit Pack
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911hillclimber
- Nurse, I think I need some assistance
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- Location: West Midlands
Re: case bolt orientation
You might get new O rings (mine were blue) from type911. They sell some gaskets as singles as well as the full gasket sets.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
- AndrewSlater
- I luv DDK!
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Re: case bolt orientation
Thanks the response - unfortunately they aren't an in stock item at type911 so ordered some from RosePassion along with some new bevelled washers - unfortunately the case bolt is NLA.
Tempted to do them all again one at a time and maybe skip the RTV this time.
Oh well got a few days to stew over it.
Tempted to do them all again one at a time and maybe skip the RTV this time.
Oh well got a few days to stew over it.
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
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210bhp
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Re: case bolt orientation
Hi Andrew

I might have a bolt but need to check.
Regards
Mike
Sent from my iPhone using Tapatalk

I might have a bolt but need to check.
Regards
Mike
Sent from my iPhone using Tapatalk
_____________________________
73 RS (Sold)
67 S
Mint T (Sold)
996 Turbo (Sold)
73 2.4E (home after 25 years) and Sold again
73T targa (signal yellow project)
1953 Vauxhall Velox
914/6
1963 356B
https://www.mybespokeroom.com/
73 RS (Sold)
67 S
Mint T (Sold)
996 Turbo (Sold)
73 2.4E (home after 25 years) and Sold again
73T targa (signal yellow project)
1953 Vauxhall Velox
914/6
1963 356B
https://www.mybespokeroom.com/
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Lightweight_911
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Re: case bolt orientation
I sold a couple of sets of case bolts a few months ago but there may be a slight chance I've got an odd one still - I'll check later today & report back.
Andy
“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
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MT
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Re: case bolt orientation
Sorry to hijack the thread but if anyone has a couple of case bolt dome nuts and washers then I'm in need! (not the bolts themselves)
Mick
Mick
'Creativity is the product of time wasted' Albert Einstein
1972 RHD 2.4E (ex Bob Watson racer - now in original Tangerine)
1966 LHD swb (Doctors car - now with Mrs. Ferrari in Madrid)
1966 TR4A (now sold and replaced by 1990 944 turbo)
1966 S2a Landrover
1972 RHD 2.4E (ex Bob Watson racer - now in original Tangerine)
1966 LHD swb (Doctors car - now with Mrs. Ferrari in Madrid)
1966 TR4A (now sold and replaced by 1990 944 turbo)
1966 S2a Landrover
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Lightweight_911
- Nurse, I think I need some assistance
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Re: case bolt orientation
Sorry - didn't find any ...
Andy
“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
- AndrewSlater
- I luv DDK!
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Re: case bolt orientation
Thanks for checking Andy - no problem.
Thanks for the smiley face Mike - made me chuckle!
Thanks for the smiley face Mike - made me chuckle!
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
1974 Porsche 911 2.7 (The Manhattan project) viewtopic.php?f=28&t=51455
1973 VW 914 1.7 Olympic Blue - ( gone to a good home )
-
210bhp
- Nurse, I think I need some assistance
- Posts: 8250
- Joined: Sat Feb 28, 2004 12:28 am
- Location: Scotland
Re: case bolt orientation
Hi Andrew
I have an enormous box full of new seals gaskets and washers etc so if you need the odd one or twelve let me know.
I have still to check on the bolt.
Regards
Mike
I have an enormous box full of new seals gaskets and washers etc so if you need the odd one or twelve let me know.
I have still to check on the bolt.
Regards
Mike
_____________________________
73 RS (Sold)
67 S
Mint T (Sold)
996 Turbo (Sold)
73 2.4E (home after 25 years) and Sold again
73T targa (signal yellow project)
1953 Vauxhall Velox
914/6
1963 356B
https://www.mybespokeroom.com/
73 RS (Sold)
67 S
Mint T (Sold)
996 Turbo (Sold)
73 2.4E (home after 25 years) and Sold again
73T targa (signal yellow project)
1953 Vauxhall Velox
914/6
1963 356B
https://www.mybespokeroom.com/
-
stuby
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Re: case bolt orientation
I have a complete case, with bolts....
Don't shoot the messenger....He's only doing his job!

