986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post

Gelbster · 06-19-2017, 02:58 PM

It depends if you want speculation or diagnosis :-).
Get the car up on a lift. Use an engine ear(electronic stethoscope ) to pinpoint the exact location and source point of the noise.
Yes, it seems like lifters but is it both banks? Is it lifters or bore scoring or just the exhaust expanding with heat or a loose spark plug ?
Whatever , the fix is time consuming and the parts expensive. So diagnosis is key to avoid wasting time & $.
When you get the cams off and extract the lifters, you need advice on what to look for to confirm you found the source of the noise problem. Can you imagine a re-do ?
The tappet inside the bucket may be jammed in the fully compressed position or it may be weak. In theory , prodding a weak lifter tappet with a wood dowel should give you a clue about which are weak/strong. Be sure to put each lifter in a designated storage box(egg carton?) so you replace them in the same position if they are still good.
If they are the original lifters and the engine is over 80K miles I would replace anyway - you've gone that far.
The lifters used to be very expensive but now the Interchange manuals have caught up with INA and you can find a BMW cross reference that allegedly is the same as the Porsche part. $21 each x 24 =!
But if you google the INA interchange part they are $12 each ! Heluva difference on 24 !But verify the number before you buy :
INA - 11321748884 or 4200049100
The Porsche price is around $70 each .
You should be able to get all 24 for less than $300 delivered with tax minus a discount.
Yes you can do this job with the engine in place but as an expert (Not me) said - "it's like building a ship in a bottle'.
The pioneer of this job was Doug Harn - google for his and subsequent posts on the subject "Dharn" is his Forum name.
In theory you can try some snake oil treatments Motor Medic, Rislone.... see Youtube.
Also on You tube ,there are plenty of sound clips for Boxster/996 lifter noise for you to compare with yours.
There is also an issue with wear in the lifter carrier. You'll know the carrier was worn because if you put new lifters in a worn carrier the noise will still be there/will return quickly ! In theory you can measure the bores in the lifter carrier for ovality/taper.... but there are no specs.
Replacing the lifter carrier gets expensive.
https://rennlist.com/forums/996-forum/623466-lifter-noise-2.html

06-19-2017, 02:58 PM	#3
Gelbster Registered User Join Date: May 2014 Location: S.California Posts: 2,029	It depends if you want speculation or diagnosis :-). Get the car up on a lift. Use an engine ear(electronic stethoscope ) to pinpoint the exact location and source point of the noise. Yes, it seems like lifters but is it both banks? Is it lifters or bore scoring or just the exhaust expanding with heat or a loose spark plug ? Whatever , the fix is time consuming and the parts expensive. So diagnosis is key to avoid wasting time & $. When you get the cams off and extract the lifters, you need advice on what to look for to confirm you found the source of the noise problem. Can you imagine a re-do ? The tappet inside the bucket may be jammed in the fully compressed position or it may be weak. In theory , prodding a weak lifter tappet with a wood dowel should give you a clue about which are weak/strong. Be sure to put each lifter in a designated storage box(egg carton?) so you replace them in the same position if they are still good. If they are the original lifters and the engine is over 80K miles I would replace anyway - you've gone that far. The lifters used to be very expensive but now the Interchange manuals have caught up with INA and you can find a BMW cross reference that allegedly is the same as the Porsche part. $21 each x 24 =! But if you google the INA interchange part they are $12 each ! Heluva difference on 24 !But verify the number before you buy : INA - 11321748884 or 4200049100 The Porsche price is around $70 each . You should be able to get all 24 for less than $300 delivered with tax minus a discount. Yes you can do this job with the engine in place but as an expert (Not me) said - "it's like building a ship in a bottle'. The pioneer of this job was Doug Harn - google for his and subsequent posts on the subject "Dharn" is his Forum name. In theory you can try some snake oil treatments Motor Medic, Rislone.... see Youtube. Also on You tube ,there are plenty of sound clips for Boxster/996 lifter noise for you to compare with yours. There is also an issue with wear in the lifter carrier. You'll know the carrier was worn because if you put new lifters in a worn carrier the noise will still be there/will return quickly ! In theory you can measure the bores in the lifter carrier for ovality/taper.... but there are no specs. Replacing the lifter carrier gets expensive. https://rennlist.com/forums/996-forum/623466-lifter-noise-2.html Last edited by Gelbster; 06-19-2017 at 04:15 PM.