Documented forum build · 986 Boxster · water-cooled
2000 Boxster S DIY engine repair
A nine-page home repair and reassembly following metal in the oil filter, an IMS bearing failure and internal bearing damage, with owner updates through almost 10,000 miles.
Evidence: Opening post · Failed IMS bearing · Number-six bearing and internal wear · Selective repair scope, machine work and lower-end assembly · Piston and case assembly · Almost 10,000-mile follow-up
- Vehicle
- 2000 Porsche Boxster S
- Engine
- M96 flat six; exact displacement and engine code not stated in the thread → Budget-conscious DIY M96 repair and reassembly retaining the original pistons, bores and most piston rings
- Forum
- 986 Forum
- Thread author
- flaps10 · 22 September 2014
Vehicle and engine evidence: Complete 986 Forum thread · Opening post · Selective repair scope, machine work and lower-end assembly · Budget reuse decision · Piston and case assembly
Why it came apart
Metal appeared in the oil filter. The strip then found a failed double-row IMS bearing, a spun number-six connecting-rod bearing, marked main bearings, a broken oil-control ring and a scored cylinder.
Source: Opening post · Failed IMS bearing · Number-six bearing and internal wear
What the project aimed to do
Return the existing engine to service within a limited budget, accepting selective reuse rather than defining a recommended performance specification.
Source: Selective repair scope, machine work and lower-end assembly · Budget reuse decision
Who did what
The owner carried out and documented the removal, teardown and assembly; a machine shop cleaned, inspected and polished selected parts.
Source: Selective repair scope, machine work and lower-end assembly · Piston and case assembly
The author calls the engine an M96. The thread does not explicitly state its displacement or full engine code.
Vehicle context: Complete 986 Forum thread · Opening post
Documented sequence
Teardown and IMS diagnosis
Metal in the filter led to engine removal and a full strip, where the failed double-row IMS bearing was identified.
Source: Opening post · Failed IMS bearing · Decision to open the complete engine
Internal damage assessment
The author documents the spun number-six rod bearing, marked mains, broken oil-control ring and cylinder damage.
Inspection and machine work
Parts received ultrasonic cleaning, the crankshaft was Magnaflux inspected and polished, and the bearing carrier and clearances were reviewed before assembly.
Source: Selective repair scope, machine work and lower-end assembly
DIY assembly
The owner documents new lower-end bearings, oil spray nozzles and chain guides, the EPS IMS roller bearing and oil-feed modification, reused cylinder components, then piston and case reassembly.
Source: Selective repair scope, machine work and lower-end assembly · Budget reuse decision · EPS IMS bearing and oil-feed installation · Piston and case assembly
Startup and mileage follow-up
After correcting a loose cylinder-three connector, the engine ran; later posts report conditions at 909 miles and almost 10,000 miles.
Source: First running result · 909-mile and cost follow-up · Almost 10,000-mile follow-up
Named components and work
Bearings and connecting rod
New main, thrust and connecting-rod bearings, a used replacement number-six connecting rod and ARP rod bolts.
Source: Selective repair scope, machine work and lower-end assembly · IMS sprocket set-screw retention
IMS and timing components
EPS IMS roller bearing with its oil-feed modification, new oil spray nozzles and IMS-chain guides; the thread also records the author's set-screw and JB Weld method intended to retain the IMS sprocket.
Source: Selective repair scope, machine work and lower-end assembly · EPS IMS bearing and oil-feed installation · IMS sprocket set-screw retention
Reused cylinder components
The owner reused the pistons, bores and most rings as a budget decision despite the documented wear and damage.
Source: Budget reuse decision
Reported outcomes
Early running result
Engine returned to service
At 160 miles the author reported good operation and a small coolant seep; this was not a dyno-tested result.
Source: First running result · 160-mile running report
Owner-reported cost
$2,816 plus about $300 possibly omitted
Historical, self-reported receipts at 909 miles; labour and the completeness of the total were not audited.
Source: 909-mile and cost follow-up
Latest identified follow-up
Almost 10,000 miles
Mileage reported by the author after the engine returned to service; no teardown or independent inspection accompanies it.
Source: Almost 10,000-mile follow-up
Evidence limits
- The forum thread does not explicitly state the engine displacement or complete engine code.
- The cost total and mileage are owner-reported and not independently audited.
- No dyno result is published.
- Reuse decisions, the EPS IMS installation and the author's set-screw and JB Weld choice are recorded as history, not recommended technical instructions.
- Some externally hosted thread photographs may have disappeared.
Access note: All nine pages were publicly readable without an account; some externally hosted photographs may no longer load.
Reviewed source trail
- Complete 986 Forum thread · reviewed 2026-08-23
- Opening post · reviewed 2026-08-23
- Failed IMS bearing · reviewed 2026-08-23
- Decision to open the complete engine · reviewed 2026-08-23
- Number-six bearing and internal wear · reviewed 2026-08-23
- Selective repair scope, machine work and lower-end assembly · reviewed 2026-08-23
- Budget reuse decision · reviewed 2026-08-23
- EPS IMS bearing and oil-feed installation · reviewed 2026-08-23
- IMS sprocket set-screw retention · reviewed 2026-08-23
- Piston and case assembly · reviewed 2026-08-23
- First running result · reviewed 2026-08-23
- 160-mile running report · reviewed 2026-08-23
- 909-mile and cost follow-up · reviewed 2026-08-23
- Almost 10,000-mile follow-up · reviewed 2026-08-23