S engine rebuild - DIY repair path?
01-14-2016, 08:41 PM
#16
Advanced
Thread Starter
Still waiting for my engine block to return... so nothing to report until block comes back..
I am curious to know if V8 Touareg has this issue and if VW publishes their piston to cylinder clearance specs? The VR6 engine in the Porsche service manual was the only Cayene engine that did publish this information.
Last edited by matt_o_70; 04-18-2016 at 10:19 PM.
01-15-2016, 12:01 AM
#17
Three Wheelin'
The Audi 4.2l engine in the Touareg is a rock solid motor. They've been building them in one version or another (belt drive cams, chain drive cams, port injection, Direct Injection) for over 15yrs. The Blocks haven't changed much, just the heads and ancillary. They've been built from 300bhp to 480bhp (C5 Audi RS6+) to the top Gumpert Apollo, 800bhp). Rock solid. The top 4.2FSI engine is comparable to the Cayenne S but nothing in N. America comparable to a CTTS. In Europe (really ROW) the Q7 had a limited edition neck twisting V12 TDI with 500bhp and 740 lb-ft of Tq. Wish we could at least get the 4.2TDI here, it's got 280bhp and 630 lb-ft.
01-15-2016, 07:37 AM
#18
Nordschleife Master
If you have custom pistons made the supplier of those parts will give you the piston to cylinder wall clearance for your application. I wouldn't trust any piston clearance values from Porsche in regards to the V8. Have you contacted JE? Lots of guys from the 944 board use them and have had good luck with them.
04-18-2016, 10:18 PM
#19
Advanced
Thread Starter
Qty oil pump / pickup (illustration 104-01)
1 94810725200 oil pump chain
1 99970753040 oil suction tube o-ring
1 99970751340 oil suction tube o-ring
1 99970749740 oil tube o-ring
1 99970749640 oil tube o-ring
Oil filter bracket / heat exchanger (104-10)
5 99970749840 o-ring
1 94810720101 gasket
2 94810717500 gasket
Alternator water cooling (105-10)
1 99970753740 o-ring
3 99970751440 o-ring
1 00004320468 synthetic o-ring grease
Water pump housing (105-00)
1 94810611503 pump gasket
1 99970747740 o-ring
1 94810612303 gasket
1 94810640101 sealing ring
1 99970750240 o-ring
water bridge / cooling tubes (105-05)
2 94810615305 gasket
2 99970737041 o-ring
4 99970751741 o-ring
2 99970751841 o-ring
intake (107-10)
2 94811014501 intake gasket
exhaust manifold (202-00)
2 94811117101 manifold gasket
24 99908464705 M8 locknut
24 N90879702 M8 x 25 stud
2 95511111300 front cat gasket
block (101-05)
2 94810121600 cap
1 94810119702 gasket
1 99970748140 o-ring
1 99970736040 o-ring
9 94810774000 sealing ring
1 99970739640 o-ring
10 94810118901 M12 Main bolt
10 94810119100 M10 cradle Bolt
Camshaft alignment tools: 72196780 - PN for reference, DIY this ands save a few bucks.
thinking I should locate a manual tranny and make this worthwhile...
1 94810725200 oil pump chain
1 99970753040 oil suction tube o-ring
1 99970751340 oil suction tube o-ring
1 99970749740 oil tube o-ring
1 99970749640 oil tube o-ring
Oil filter bracket / heat exchanger (104-10)
5 99970749840 o-ring
1 94810720101 gasket
2 94810717500 gasket
Alternator water cooling (105-10)
1 99970753740 o-ring
3 99970751440 o-ring
1 00004320468 synthetic o-ring grease
Water pump housing (105-00)
1 94810611503 pump gasket
1 99970747740 o-ring
1 94810612303 gasket
1 94810640101 sealing ring
1 99970750240 o-ring
water bridge / cooling tubes (105-05)
2 94810615305 gasket
2 99970737041 o-ring
4 99970751741 o-ring
2 99970751841 o-ring
intake (107-10)
2 94811014501 intake gasket
exhaust manifold (202-00)
2 94811117101 manifold gasket
24 99908464705 M8 locknut
24 N90879702 M8 x 25 stud
2 95511111300 front cat gasket
block (101-05)
2 94810121600 cap
1 94810119702 gasket
1 99970748140 o-ring
1 99970736040 o-ring
9 94810774000 sealing ring
1 99970739640 o-ring
10 94810118901 M12 Main bolt
10 94810119100 M10 cradle Bolt
Camshaft alignment tools: 72196780 - PN for reference, DIY this ands save a few bucks.
thinking I should locate a manual tranny and make this worthwhile...
Last edited by matt_o_70; 05-12-2016 at 10:54 PM.
05-12-2016, 10:53 PM
#20
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Thread Starter
05-15-2016, 11:11 AM
#21
I hope you marked all the hydraulic tappets when you removed them because they need to go into the same spots. Otherwise you will need new ones @ 25$- 50$ ea. New x 32. I'm seeing good used turbo engines on eBay as low as $2250-
11-28-2017, 08:51 PM
#22
4th Gear
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Cayenne engine rebuild
So looking into engine rebuild options - I have not found many informational threads to help the guy who is stuck with a 04 Cayenne S that needs an engine rebuild after it has ruined it's cylinder walls (cylinder scoring).
I have read some documentation online about the importance of proper honing process and finding a shop that has experience and desire to work with the Hypereutectic engine block and a profilometer to verify the cylinder wall finish. The machinist needs to be very familiar with the rate or removal of his chosen tooling and the abrasives chosen for this process.
http://www.engineprofessional.com/ep4.html
http://www.engineprofessional.com/ep2.html
Porsche likes to boast of the % of its total cars produced still on the road today - yet I can not find the piston to cylinder wall clearances for these engines. I have read the engine replacement thread. I am aware that these dimensions are not published. Jake also suggests that piston to cylinder wall clearance and extreme cold climate is the root cause for the cylinder damage. So it would seem the key to a successful rebuild is proper clearance to allow for the piston skirt expansion with out cylinder wall damage.
I am looking for piston & ring options to get my existing block bored to remove damaged cylinder wall and prepared for new pistons.
-Torque Plate required? locate or fabricate if necessary...
- Pin offset?
- Coated piston skirts?
The article about Hypereutectic engines suggested a few details:
- 3 step process Honing, finish honing, exposure
- MAN 845 honing oil is minimum requirement - Ideally filtered to 5 microns.
- No water based coolants should be used - contributes to sludge and adversely affects honing
- finish honing pass should result in 0.1 micron finish (ultra smooth or mirror like)
- extremely light honing force and XM27 elastomer based "stone" - is superior to any rigid abrasive or "stone"
- 0.5 micron Si crystal exposure height is typical - after proper exposure process
- Barrel shaped piston ring faces are mentioned..on coated cylinders
- DLC coatings for the piston rings may now be the Porsche parts in use
- importance of excellent machining geometry - cylindericity limits of 0.0005"
- cylinder plating maybe beneficial - but costly and requires shipping block off
Anyone been down this path care to comment or point me at other relevant threads I should read?
I have read some documentation online about the importance of proper honing process and finding a shop that has experience and desire to work with the Hypereutectic engine block and a profilometer to verify the cylinder wall finish. The machinist needs to be very familiar with the rate or removal of his chosen tooling and the abrasives chosen for this process.
http://www.engineprofessional.com/ep4.html
http://www.engineprofessional.com/ep2.html
Porsche likes to boast of the % of its total cars produced still on the road today - yet I can not find the piston to cylinder wall clearances for these engines. I have read the engine replacement thread. I am aware that these dimensions are not published. Jake also suggests that piston to cylinder wall clearance and extreme cold climate is the root cause for the cylinder damage. So it would seem the key to a successful rebuild is proper clearance to allow for the piston skirt expansion with out cylinder wall damage.
I am looking for piston & ring options to get my existing block bored to remove damaged cylinder wall and prepared for new pistons.
-Torque Plate required? locate or fabricate if necessary...
- Pin offset?
- Coated piston skirts?
The article about Hypereutectic engines suggested a few details:
- 3 step process Honing, finish honing, exposure
- MAN 845 honing oil is minimum requirement - Ideally filtered to 5 microns.
- No water based coolants should be used - contributes to sludge and adversely affects honing
- finish honing pass should result in 0.1 micron finish (ultra smooth or mirror like)
- extremely light honing force and XM27 elastomer based "stone" - is superior to any rigid abrasive or "stone"
- 0.5 micron Si crystal exposure height is typical - after proper exposure process
- Barrel shaped piston ring faces are mentioned..on coated cylinders
- DLC coatings for the piston rings may now be the Porsche parts in use
- importance of excellent machining geometry - cylindericity limits of 0.0005"
- cylinder plating maybe beneficial - but costly and requires shipping block off
Anyone been down this path care to comment or point me at other relevant threads I should read?
11-28-2017, 08:58 PM
#23
Burning Brakes
11-28-2017, 09:19 PM
#24
4th Gear
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12-22-2017, 03:37 PM
#27
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My turn for this disaster...... thinking about this option......
https://928motorsports.com/services/...ock_repair.php
https://928motorsports.com/services/...ock_repair.php
12-22-2017, 03:43 PM
#28
Nordschleife Master
My turn for this disaster...... thinking about this option......
https://928motorsports.com/services/...ock_repair.php
https://928motorsports.com/services/...ock_repair.php
12-22-2017, 04:09 PM
#29
My turn for this disaster...... thinking about this option......
https://928motorsports.com/services/...ock_repair.php
https://928motorsports.com/services/...ock_repair.php
12-28-2017, 09:59 PM
#30
Advanced
Thread Starter
All back together and back on the road for a while now. But I had a bit of problem with the engine block repair, sent it away since I had a hard time finding any local to me shop that was qualified or willing to work on Cayenne block. The guys that subcontracted the engine repair to US Chrome - then did not package my block very well (knowing how poorly things can be treated by UPS) coming back to me - and my block was damaged on way back to me. So I had to get a small piece (bolt hole) welded back onto the block.. time will tell if any other problems surface from this.
I subsequently found a very knowledgeable engine shop in the area that I would trust and would have saved me money and shipping headaches..
As a lifelong fan of the Brand it makes me sad that Porsche is not stepping up and taking care of this under a service campaign, I just can not see any way this is not a manufacturing issue. The more people who I talk to - more reports of same problem or know someone who had.
I subsequently found a very knowledgeable engine shop in the area that I would trust and would have saved me money and shipping headaches..
As a lifelong fan of the Brand it makes me sad that Porsche is not stepping up and taking care of this under a service campaign, I just can not see any way this is not a manufacturing issue. The more people who I talk to - more reports of same problem or know someone who had.
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