10 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHCan the 997 Water Pump be used on the 3.4 996 Engine?
Leading reported evidence
Use 997 impeller in the 996
Performed · outcome unconfirmed
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 performed work without a confirmed outcome
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.
Performed · outcome unconfirmed
I know many have used the 997 impeller in the 996, but I also read that some have had interference issues.
Can the 997 Water Pump be used on the 3.4 996 Engine?
Read full discussion summary
Leading evidence: 'Use 997 impeller in the 996' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Use 997 impeller in the 996' (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 performed work without a confirmed outcome
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.
Performed · outcome unconfirmed
I've used the 997 water pump for 7500 miles without any problem.
Can the 997 Water Pump be used on the 3.4 996 Engine?
Use plastic impeller
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.
Can the 997 Water Pump be used on the 3.4 996 Engine?
Coverage and how to read this overview
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.
10 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: 20261026T212127Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
I know they are interchangeable on the MKII and the 997 (at least the 3.6 version) but is that the case for the 3.4? I have a '99 C2 with the 3.4.
As always, thanks in advance!
DS
Is the 997 water pump different/improved over the 996 pump? And is there a difference between the water pump for a 3.4 vs. a 3.6?
Does the 997 still use the plastic impeller?
From what I understand, still composite impeller, but there were some changes. On Renntech, they mention that it is interchaneable with the MKII, but no one was sure if it was with the MKI. Fast Street advises he was able to have it done.
Thanks!
I thought the 996 and the 997 water pump had the same housing, but a different impeller size. I know many have used the 997 impeller in the 996, but I also read that some have had interference issues.
https://rennlist.com/forums/996-foru...ller-size.html
https://rennlist.com/forums/996-foru...er-at-53k.html
https://rennlist.com/forums/996-foru...ater-pump.html
One thing is for sure, Porsche still has a different part number for the 996 and 997 pump. I decided not to risk it, and just ordered the 996 OEM pump (996-106-011-56)
I also found this. Looks like a German aftermarket parts supplier. They list the 996 impeller diameter at 65mm, and the 997 impeller at 67mm.
http://www.laso.de/pdf/pkw2009/PORSC...hermostats.pdf
Thanks for the info Frisbee, I ended up doing the same thing. While it's not my DD, I still want to get her back in good shape as quick as i can, and didn't want to find out the hard way it wouldn't quite fit.
Cheers,
DS
For a track car, might the 65mm impeller not be a better way to go? Cutting down the WP impeller on race engines (for other makes where there is no option) is rather common to prevent cavitation @ high RPM.
This is a source reference. Confirm exact model applicability in the original material.
