Documented forum build · 996 · water-cooled
1998 996 Carrera 3.4 rebuild
An owner-documented removal and refit around a Hartech long-block rebuild, followed from metal found in the filter to an 850-mile trip after run-in.
Evidence: Opening filter evidence and oil-pressure report · Workshop inspection findings · Delivered rebuild specification · First start · 850-mile follow-up
- Vehicle
- 1998 Porsche 996 Carrera 2 manual
- Engine
- 3.4-litre M96 flat six → Rebuilt 3.4-litre M96 with six Nikasil-plated alloy liners and forged pistons
- Forum
- 911UK
- Thread author
- Jamesx19 · 7 April 2018
Vehicle and engine evidence: Complete 911UK thread · Workshop inspection findings · Delivered rebuild specification
Why it came apart
The owner found silver non-ferrous particles and two bronze-coloured flakes in the oil filter, with hot oil pressure slightly below 1 bar.
What the project aimed to do
Retain the 3.4-litre capacity and dual-mass flywheel while addressing the internal wear and known rebuild items found during inspection.
Source: Chosen specification · Delivered rebuild specification
Who did what
The owner documented engine removal and refit; Hartech inspected and supplied the rebuilt long block.
Source: Complete 911UK thread · Delivered rebuild specification
The author reports a 3.4-litre M96 engine at 92,000 miles.
Vehicle context: Complete 911UK thread · Workshop inspection findings · Delivered rebuild specification
Documented sequence
Filter evidence and inspection
The thread begins with debris found in the filter; the later Hartech inspection is reported to have found a main bearing worn through to copper and light cylinder marking.
Source: Opening filter evidence and oil-pressure report · Workshop inspection findings
Specification decision
The owner records the selected scope and then the specification actually delivered after the engine was opened.
Source: Chosen specification · Delivered rebuild specification
Reinstallation and first start
After refit, the first-start fault was traced to swapped camshaft and crankshaft sensor connectors; the corrected engine then started without a reported leak.
Source: First start
Run-in and filter inspection
The owner documented the run-in procedure and later reported no new debris in the filter.
Source: Run-in notes · Post-run-in filter check
850-mile journey
The car completed a reported 850-mile trip, with the engine described as responsive and stronger above roughly 4,200–4,500 rpm.
Source: 850-mile follow-up
Named components and work
Cylinders and pistons
Six Nikasil-plated alloy liners and six Wössner 4032 forged pistons, with the original 3.4-litre displacement retained.
Source: Delivered rebuild specification
IMS and timing drive
Modified IMS with a larger bearing and sprocket, plus chains, guides and tensioners.
Source: Delivered rebuild specification
Bottom end and heads
New bearings, ARP connecting-rod bolts and reconditioned cylinder heads are included in the delivered specification.
Source: Delivered rebuild specification
Cooling and exhaust additions
Low-temperature thermostat, oil-pump spring and stainless exhaust manifolds are recorded alongside the engine work.
Source: Delivered rebuild specification
Reported outcomes
First-start result
Started after connector correction
The author reported no leak after correcting the swapped sensor connectors.
Source: First start
Post-run-in filter
No new debris reported
A visual owner check, not a laboratory oil analysis.
Source: Post-run-in filter check
Road follow-up
850-mile trip completed
The owner reported normal operation and stronger response above about 4,200–4,500 rpm.
Source: 850-mile follow-up
Evidence limits
- No dyno test or measured power figure is published in the reviewed thread.
- Diagnosis and road results are reported by the owner and workshop, not independently verified.
- The identified follow-up ends in November 2018 and does not establish present condition.
Access note: All twelve pages reviewed were publicly readable; an account is needed only to reply.
Reviewed source trail
- Complete 911UK thread · reviewed 2026-08-23
- Opening filter evidence and oil-pressure report · reviewed 2026-08-23
- Workshop inspection findings · reviewed 2026-08-23
- Chosen specification · reviewed 2026-08-23
- Delivered rebuild specification · reviewed 2026-08-23
- First start · reviewed 2026-08-23
- Run-in notes · reviewed 2026-08-23
- Post-run-in filter check · reviewed 2026-08-23
- 850-mile follow-up · reviewed 2026-08-23