Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
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- Aidan
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
Pelican in the states sell what they state are genuine Porsche ones, same as ours
link to Pelican
link to Pelican
AIDAN 
- Aidan
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
GoWesty's solution seems to be to add a set of lash caps, and I pressume their set of screws, that's what they say is in their new build engines
lash cap kit
lash cap kit
AIDAN 
Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
Aidan wrote: ↑11 May 2026, 13:07 GoWesty's solution seems to be to add a set of lash caps, and I pressume their set of screws, that's what they say is in their new build engines
lash cap kit
Yes. Have ordered a set.
MaxStu
1987 2.1 Automatic Carb/LPG Autosleeper.
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1987 2.1 Automatic Carb/LPG Autosleeper.
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
Thanks for your help and support.
Have also order an auto diff sump plug kit.
https://gowesty.com/products/differenti ... ce=youtube
MaxStu
1987 2.1 Automatic Carb/LPG Autosleeper.
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1987 2.1 Automatic Carb/LPG Autosleeper.
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silverbullet
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
20USD each. Plus shipping and duties. Not really viable and if they are Genuine Porsche that suggests that they are available on this side of the Atlantic Ocean.Aidan wrote: ↑11 May 2026, 12:32 Pelican in the states sell what they state are genuine Porsche ones, same as ours
link to Pelican
Our neighbour at the works does CNC turning, I could work up a quote for decent quality ones, deep case hardened. VW were big on induction hardening for valvetrain parts (including cam lobes) but no reason not to do it by another means.
Otherwise it means putting them in a heatsink to keep the threads unhardened and the additional handling drives the cost up quite quickly.
Heat treatment costs are are horrific these days, they burn a lot of gas so minimum charges for good work are north of £180 + vat
1985 Oettinger 3.2 Caravelle RHD syncro twin slider. SA Microbus bumpers, duplex winch system, ARC 7X15 period alloys
Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
I had a look as the Pelican supply.
One common theme noted about the poor quality versions that fail prematurely. They all have tapered heads. Whereas the genuine VW ones don't.
Pelican are tapered. Gowesty are displaying stock with non tapered heads yet still aftermarket? Order in place.
Aftermarket 10mm on left after 1800 miles. Genuine VW 9mm for reference. But same shape as a 10mm genuine VW.


One common theme noted about the poor quality versions that fail prematurely. They all have tapered heads. Whereas the genuine VW ones don't.
Pelican are tapered. Gowesty are displaying stock with non tapered heads yet still aftermarket? Order in place.
Aftermarket 10mm on left after 1800 miles. Genuine VW 9mm for reference. But same shape as a 10mm genuine VW.


MaxStu
1987 2.1 Automatic Carb/LPG Autosleeper.
"Blissfully happy in your presence".
1987 2.1 Automatic Carb/LPG Autosleeper.
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- Aidan
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
I had a message exchange with Mark over in Holland at Dream and Drive, he builds 2.5wbx using GoWesty kit, he uses the ones from VW ClassicParts which he gets from his local supplier, he's not reporting any issues, and I know he's had engines back in the garage for servicing
Heritage say there's are the VWClassicParts ones IIRC
here's the link to dutch supplier Boelm
Slightly tapered head in pic which is lifted from Classic I think
Heritage say there's are the VWClassicParts ones IIRC
here's the link to dutch supplier Boelm
Slightly tapered head in pic which is lifted from Classic I think
AIDAN 
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silverbullet
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
The correct way to make them would be to use a deep case hardening steel. Have the threads copper plated to mask them off and prevent them becoming brittle when the heads are hardened.
But how much to people want to pay for them?
But how much to people want to pay for them?
1985 Oettinger 3.2 Caravelle RHD syncro twin slider. SA Microbus bumpers, duplex winch system, ARC 7X15 period alloys
Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
Well l'm close to 100 quid out of pocket because of this. Plus the fuel economy drops considerably when they start to go.
The first signs are low tick over and poor fuel economy. Then suddenly, on a cold start up, the engine starts clattering like a gaggle of geese and performance drops. And then there is the aggro of replacing the damaged one.
Happy to pay a premium once and be assured the engine is reliable.
The first signs are low tick over and poor fuel economy. Then suddenly, on a cold start up, the engine starts clattering like a gaggle of geese and performance drops. And then there is the aggro of replacing the damaged one.
Happy to pay a premium once and be assured the engine is reliable.
MaxStu
1987 2.1 Automatic Carb/LPG Autosleeper.
"Blissfully happy in your presence".
1987 2.1 Automatic Carb/LPG Autosleeper.
"Blissfully happy in your presence".
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silverbullet
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
I have compared some "fair/used" condition original screws against two different pattern ones.
OEM Show a distinct blue heat treatment zone on both ends. This preserves the toughness of the working threads, makes sense.
One of the patterns is hardened on the valve end, but not the other. This has a chamfered slotted end.
The contact patch on all of these is variable.
The last one has no heat treatment zone visible, tests as all hard (needle file, no scratch) and has a full size head like OEM but has a chamfer on the valve end, reducing its useable contact width, so would only be suitable for use with a very mild DF/DG cam.
I will have to do a CAD sketch to work out the contact radius required.
The more that I think about it, the more that I like the Porsche elephant foot type screws. They wouldn't have designed that for no reason.
OEM Show a distinct blue heat treatment zone on both ends. This preserves the toughness of the working threads, makes sense.
One of the patterns is hardened on the valve end, but not the other. This has a chamfered slotted end.
The contact patch on all of these is variable.
The last one has no heat treatment zone visible, tests as all hard (needle file, no scratch) and has a full size head like OEM but has a chamfer on the valve end, reducing its useable contact width, so would only be suitable for use with a very mild DF/DG cam.
I will have to do a CAD sketch to work out the contact radius required.
The more that I think about it, the more that I like the Porsche elephant foot type screws. They wouldn't have designed that for no reason.
1985 Oettinger 3.2 Caravelle RHD syncro twin slider. SA Microbus bumpers, duplex winch system, ARC 7X15 period alloys
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silverbullet
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
1985 Oettinger 3.2 Caravelle RHD syncro twin slider. SA Microbus bumpers, duplex winch system, ARC 7X15 period alloys
- tobydog
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Re: Replacing 10mm With 9mm Valve Adjusters in DJ2.1 Engine.
silverbullet wrote: ↑13 May 2026, 12:32 The correct way to make them would be to use a deep case hardening steel. Have the threads copper plated to mask them off and prevent them becoming brittle when the heads are hardened.
But how much to people want to pay for them?
Be interesting to test them on a hardness tester, I know someone who has one.
Seen some made of H13. Wonder if 2767 (NiCr) or even Silver Steel would do. Used to make simple press tool punches out Silver Steel as an apprentice, hardened and tempered by flame.
Just my tuppence...
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