964 C4 light refurb
#796
Rennlist Member
Thread Starter
Cams timed. It took a lot longer than I thought as I failed to position the cams in the correct position as the markings were indistinct.
Cam bolts torqued to 110 Nm. The other nuts were 10 Nm.
Cam bolts torqued to 110 Nm. The other nuts were 10 Nm.
#797
Rennlist Member
Thread Starter
Followers/tappets installed on one side. An interesting point I picked up from Wayne's book is that the flange thickness is different depending on the position. As the follower shaft is shorter than the total width you change the depth of the shaft depending on the flange width.
#798
Burning Brakes
Great stuff...
What you observed answered much of my question on rocker installation... I was watching a yt video of an older engine being assembled and he mentioned that each rocker shaft should be centered to rocker and not aligned based on the edge of casing...
I will have to check my cam pics, but I am not sure I had all those punch marks on end of cam, think I only had one per cam ...
What you observed answered much of my question on rocker installation... I was watching a yt video of an older engine being assembled and he mentioned that each rocker shaft should be centered to rocker and not aligned based on the edge of casing...
I will have to check my cam pics, but I am not sure I had all those punch marks on end of cam, think I only had one per cam ...
#799
Rennlist Member
Thread Starter
You've got it but I'll add a few more pics.
The rockers are done in sequence, 1,2,3 & 4,5,6.
The rocker shafts are inserted without the bolts and nuts.
The rocker shafts are inserted at a depth that ensures they are centred on the opening. This means that their position relative to the flanges differs. If you put them all next to the flange edge some will be off centre.
The bolts and nuts are inserted after the follower and shaft are positioned. The bolt and nuts are torqued to 20Nm. Always tighten with the small hex nut.
The rockers are done in sequence, 1,2,3 & 4,5,6.
The rocker shafts are inserted without the bolts and nuts.
The rocker shafts are inserted at a depth that ensures they are centred on the opening. This means that their position relative to the flanges differs. If you put them all next to the flange edge some will be off centre.
The bolts and nuts are inserted after the follower and shaft are positioned. The bolt and nuts are torqued to 20Nm. Always tighten with the small hex nut.
#801
Rennlist Member
Thread Starter
Cam settings were perfect prior to disassembly. In hindsight I should have marked the cam tops at that stage as I knew it was right. My left cam has a clear white dot which I failed to put exactly at the top. The right cam has no similar dot. By the time you get to timing, the cams are nicely sealed. I didn't want to reverse that and pull them out. Lesson learned.
#803
Rennlist Member
Thread Starter
Chain timing cover. So many places to leak.
Lots of Dow 111 should sort it out. 6Nm of torque on the nuts. A good squeeze out gives me confidence I've done the best I could to avoid leaks.
Lots of Dow 111 should sort it out. 6Nm of torque on the nuts. A good squeeze out gives me confidence I've done the best I could to avoid leaks.
Last edited by John McM; 08-01-2017 at 11:45 PM.
#806
Rennlist Member
Thread Starter
Large oil line connected and heat exchangers on. Copper grease and all new fasteners. NB: I decided not to take a grinder to the joint between the right and left exchangers as the unit comes off easily as a whole.
#808
Rennlist Member
Thread Starter
Time for a break from engine building and actually have a drive.
I spent last weekend with up to seven other Porsches, and we ripped through 900km of NZ's great back roads. The Silver C4 was faultless. Next weekend we fly back to where we left the cars and will do another 1,100km. Life is good.
I spent last weekend with up to seven other Porsches, and we ripped through 900km of NZ's great back roads. The Silver C4 was faultless. Next weekend we fly back to where we left the cars and will do another 1,100km. Life is good.