7 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH996 Valve Job
Leading reported evidence
Check cracks
Suggestion or failed attempt
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Leading evidence: 'Check cracks' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check cracks' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
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Suggestion · Original poster
Took heads to machine shop to level deck and replace exhaust valve guides.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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Suggestion
If you are replacing the guides be careful with the reaming/ fitting process.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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Suggestion · Original poster
I'm still debating if I'm going to replace all the springs, but will be measuring them at the lift range points at a minimum to see what I'm dealing with before racing to decisions.
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Suggestion · Original poster
I'm still debating if I'm going to replace all the springs, but will be measuring them at the lift range points at a minimum to see what I'm dealing with before racing to decisions.
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Suggestion · Original poster
I'll likely get some/most of this from the machine shop I'm working with, but curious if anyone has done this or used an specific reference data/material to guide their way.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
7 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T161109Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Working on 996.1 3.4 heads. Took heads to machine shop to level deck and replace exhaust valve guides. As part of my DIY development, doing the valve job myself. Ordered neway guide/cutters to cut the seats and will resurface valves that are concentric and in good shape. Curious if anyone has done this DIY and if they have any tips and/or specs for ranges on valve stem, concentricity, valve height and spring compression. I'll likely get some/most of this from the machine shop I'm working with, but curious if anyone has done this or used an specific reference data/material to guide their way.
Do a lot of reading on M96 valve seats, they are thin and not super robust, they can drop and cause carnage. I'm not sure what the options are but I'm sure you can find more info on here
Check the valve guide/ valve clearance. If the guides are worn there's no way for the valve job to be held with concentric standards. If you are replacing the guides be careful with the reaming/ fitting process.
It looks like you are working with an M96.01/02/04 cylinder head, so definitely replace the valve springs.
I found this great
article
by Len Hoffman that details his insights. Seem like this is more of an issue for the 997 than 996, but also depends on whether the car has been operating at great length with worn guides and bouncy springs. That's the primary reason I'm having them checked out at a machine shop and regardless if in spec, having all the exhaust guides replaced. Unless any issues with intake, leaving those alone.
Agreed on guide work, and having that done by a professional. I'm still debating if I'm going to replace all the springs, but will be measuring them at the lift range points at a minimum to see what I'm dealing with before racing to decisions.
Agreed Len Hoffman is an excellent source. He's got both of my heads now. Seats and springs all around. There are good choices of race car seats that hold up. Springs from 997's.
Make sure you are checking for cracks. These heads are known for that. One of mine is cracked. When i called my local shop to see if they had any 996 heads, they said they a pile of cracked ones.
Best,
This is a source reference. Confirm exact model applicability in the original material.
