Page 1 of 1
Specs for oil relief/bypass valve springs in 912 motor
Posted: Fri May 02, 2008 3:29 pm
by Tom Frisardi
Can someone, please, tell me the wire diameter and free length of the springs for the oil pressure relief and bypass valve springs in a 1968 912 motor? The parts manual says they are the same, but I don't have the data. Are the earlier motors superseded to the same, identical springs? Also, what is the correct overall length of the pistons for the two applications?
Thanks in advance.
Posted: Fri May 02, 2008 4:01 pm
by Brad Ripley
Info is right there in your Spec Book, bottom page 25, top page 26.
Both the spring in the crankcase and the timing cover should be the same free 66 mm length, 1,40 wire crossection and 4.7 kp +- 7% compressed at 46 mm length. Part number: 999 521 016 00, $1.95 each.
Note, springs were different lengths in the early days, but superceded to the same spring in later days.
Specs for oil relief/bypass valve springs in 912 motor
Posted: Fri May 02, 2008 11:38 pm
by Guest
Tom,
Wire diameter is 1.4 mm and free length is 66 mm and if you want to
go further it has a tension of 10.35 lbs. at 46 mm. BTW all this is in
the Porsche spec book.
This for the horizontal spring/piston. This regulates the oil
pressure from the pump.
Alan
Tom Frisardi wrote:
Can someone, please, tell me the wire diameter and free length of the
springs for the oil pressure relief and bypass valve springs in a 1968
912 motor? The parts manual says they are the same, but I don't have
the data. Are the earlier motors superseded to the same, identical
springs? Also, what is the correct overall length of the pistons for
the two applications?
Thanks in advance.
------------------------------------------------------------------------
Tom Frisardi, Massachusetts
-------------------- m2f --------------------
To contact an administrator
admin@356registry.com
<mailto:
admin@356registry.com>
To unsubscribe go to
http://www.356registry.com/forum/m2f_usercp.php
Read this topic online here:
http://356registry.com/forum/viewtopic.php?p=4581#4581
-------------------- m2f --------------------
Post generated using Mail2Forum via email.
Posted: Mon May 05, 2008 9:13 am
by Tom Frisardi
Alan and Brad,
Thank you, both, for getting this info to me. I have the 356 B/C service manual and the 356 "Information Please" spec book. I could only find the specifications pertaining to different springs for the bypass and pressure valves, and don't list specs for the supersession. The motor I'm assembling is a 912, so I wanted to be sure.
I felt that I had to say something, because I always read the manual.
Tom
Posted: Mon May 05, 2008 10:31 am
by Brad Ripley
Note, the 356 Spec book indicates a supercession of the springs. The 912 Spec Book says clearly " Spring in oil pressure relief valve (crankcase) and spring in bypass valve (crankcase cover), free length 66,0
tension 4.7 kp +- 7%
wire dia 1,4 unquote.