964 C4 light refurb
#766
Rennlist Member
Thread Starter
Originally Posted by Spokes
John did add a few nice mods from mine, damn, a new job while waiting for some parts.
The hasps are more about holding things in place in normal working conditions than making it super solid. I found that the cross member holds needed to have latitude for movement otherwise I was repositioning ramps to get the hasps in.
The engine drop highlighted one more mod to make. When you want to work on your back under the front of the transmission the cross bar is annoying. I'm making a board which will bridge that bar.
#767
Burning Brakes
John,
Will you be replacing all 964-104-115-20 seal rings?
Why does PET say 11 through bolts? They all remove from passenger side of engine if left hand drive car, correct?
Will you be replacing all 964-104-115-20 seal rings?
Why does PET say 11 through bolts? They all remove from passenger side of engine if left hand drive car, correct?
#768
Rennlist Member
Thread Starter
Originally Posted by C4inLA
John,
Will you be replacing all 964-104-115-20 seal rings?
Why does PET say 11 through bolts? They all remove from passenger side of engine if left hand drive car, correct?
Will you be replacing all 964-104-115-20 seal rings?
Why does PET say 11 through bolts? They all remove from passenger side of engine if left hand drive car, correct?
There are 11 through bolts and 2 fixed studs (next to the flywheel end). The through bolts need two orings on each. The fixed studs need one oring each.
Yes, the through bolts are removed from the passenger side of a left hand drive car.
#769
Rennlist Member
Thread Starter
Three pistons and cylinders fitted. I used Porsche O-rings smeared with Curil T.
A 23mm Stomski Circlip tool helped with installation. Well worth the money.
Corrosion on the old units meant new air guides. I'm getting sick of Magnesium.
A 23mm Stomski Circlip tool helped with installation. Well worth the money.
Corrosion on the old units meant new air guides. I'm getting sick of Magnesium.
#771
Rennlist Member
Thread Starter
There was some leakage on one cylinder, but my cylinders had been modified to accept a ring and one land was chipped so I think it was due to that more than the old style leakage.
Personally, I think the cylinder head issue is overblown. I'll accept some seepage after reassembly. If it drips I'll go back in and sort it. I doubt it will do the latter as it's combustion products there not oil per se and I expect to use this car for extended periods where the fully warm engine apparently seeps less.
As an aside, my Silver C4 leaves a fair few drips but the engine operation is sweet. I cant help feeling that it's best left alone except for the easy fix leaks.
Personally, I think the cylinder head issue is overblown. I'll accept some seepage after reassembly. If it drips I'll go back in and sort it. I doubt it will do the latter as it's combustion products there not oil per se and I expect to use this car for extended periods where the fully warm engine apparently seeps less.
As an aside, my Silver C4 leaves a fair few drips but the engine operation is sweet. I cant help feeling that it's best left alone except for the easy fix leaks.
#772
Rennlist Member
Thread Starter
More progress. Second set of pistons/cylinders fitted with air guide.
Check all pistons facing the correct way (E) to intake.
Remove excess oil from bores (promotes the breaking in process)
Smear head stud threads and head stud nut flanges in copper grease, fit heads and install nuts finger tight.
Fit knock sensor rails. This is important at this stage as these bridge three cylinders and the hole positions are dependent on the cylinder barrels positions. Tighten the head studs first and you may find that the knock sensor rails won't fit, unless gorilla mechanics get hold of them risking a cross thread, but none of those in my garage
Check all pistons facing the correct way (E) to intake.
Remove excess oil from bores (promotes the breaking in process)
Smear head stud threads and head stud nut flanges in copper grease, fit heads and install nuts finger tight.
Fit knock sensor rails. This is important at this stage as these bridge three cylinders and the hole positions are dependent on the cylinder barrels positions. Tighten the head studs first and you may find that the knock sensor rails won't fit, unless gorilla mechanics get hold of them risking a cross thread, but none of those in my garage
#773
Burning Brakes
Is the leftmost bolt in second to last pic, is this a thru-bolt stud and same o-ring principle?
The knock bar bolts, what torque did you use?
Are those valve springs stock?
Did you have any carbon build up on exhaust ports? Try and clean?
Great progress ...
The knock bar bolts, what torque did you use?
Are those valve springs stock?
Did you have any carbon build up on exhaust ports? Try and clean?
Great progress ...
#774
Rennlist Member
Thread Starter
Yes, that's a through bolt, the same principle.
7 ft/lbs (10Nm) for the knock rail.
Valve springs are stock as far as I know.
General carbon build up on the heads. I cleaned it as best I could but didn't do extreme.
Tonight I will tighten the head studs. Fingers crossed nothing goes 'snap'
Last edited by John McM; 07-26-2017 at 11:15 PM.
#775
Rennlist Member
Thread Starter
Photo says it all. The torque wrench with the correct range (15Nm) is 1/4" but the 12 point tool is 1/2". I need to buy a step up adapter to correctly torque my head stud nuts
#776
Rennlist Member
Thread Starter
New cylinder head temp sensor fitted. One of those situations where I would need a special tool to be able to apply the correct torque. I just tightened it to what I felt was appropriate. When the cable is routed it can't turn to unloosen anyway.
#777
Burning Brakes
Or were you referring to a special torque wrench.
#778
Rennlist Member
Thread Starter
Originally Posted by Super90
I bought a deep socket (14mm??) and took a Dremel tool and cut a channel down the side for the cable to exit. Then torqued to spec.
Or were you referring to a special torque wrench.
Or were you referring to a special torque wrench.
#780
Rennlist Member
Thread Starter
After the head studs are tightened, remove the cam carrier, clean with rubbing alcohol and coat with Loctite 574.
Take the oil return tubes and place orings on each end coated with Dow 111. Use a piece of wood to put one end of the oil return tubes in the case opening.
Place the cam carrier over the studs while lining up the other end of the oil return tubes. Use a rubber mallet to persuade the cam carrier into place.
Place all fasteners with washers on the cam carrier. Tighten to 15Nm moving from the middle outwards.
Put assembly grease on the Cams and insert. This is to make sure they rotate freely. If they don't then loosen cam carrier fasteners and re torque.
Take the oil return tubes and place orings on each end coated with Dow 111. Use a piece of wood to put one end of the oil return tubes in the case opening.
Place the cam carrier over the studs while lining up the other end of the oil return tubes. Use a rubber mallet to persuade the cam carrier into place.
Place all fasteners with washers on the cam carrier. Tighten to 15Nm moving from the middle outwards.
Put assembly grease on the Cams and insert. This is to make sure they rotate freely. If they don't then loosen cam carrier fasteners and re torque.