Impossible Oil Leak?

[chaseincats]

17 minutes ago, cgsheen1 said:

So, none of you people live in Arizona?? Our oil cap seals were dried up, hard as a rock, and leaking 30 years ago. I still haven't found a replacement seal that I really like - most work but are a bit too soft.

There's always 400 grit and a hard block...

thezstore has replacement seals, you're just paying 20 bucks shipping for a 2 dollar piece of rubber

[Zed Head]

Don't know why I didn't go here last time, it's usually my go-to place to go to.

https://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/cylinder-head

https://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/cylinder-head/39

https://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/cylinder-head/40

 

Not really sure what these guys mean by "reproduction TPU".  Probably better than rock hard though.

https://www.ebay.com/itm/275346381999

[Yarb]

Saw that as well this morning. Worth a shot for sure.

[Zed Head]

You can even get a whole cap.  Not Nissan though.

https://www.carpartsmanual.com/datsun/Z-1969-1978/engine-280z/cylinder-head/39

https://www.sixityauto.com/gates-31109-engine-oil-filler-cap-for-15255-21b00-16920-60b02-e8dz-6766-a-15610-p2a-000-e7tz-6766-a-3022017404.html

[cgsheen1]

20 hours ago, Zed Head said:

Not really sure what these guys mean by "reproduction TPU".  Probably better than rock hard though.

TPU is a type of 3D Printer filament. It's flexible. I looked at his photo enlarged and you can see the part has been printed. 

Lucas, our local mechanical engineer, has a pretty decent 3D printer setup and tried to reproduce the boots for the fuel tank hoses under the hatch in his late 280Z using TPU. Stiffer than rubber. They turned out okay but I wouldn't call them ideal. Might work for the oil cap seal but it doesn't print very smoothly...

[Zed Head]

So it's basically a counterfeit part sold out in the open on eBay.  Nissan packaging.  

I see that the guy put some stuff in the description.  Still looks like a cover-up for somebody to buy counterfeit Nissan parts for resale.  No need to spend time on the packaging if you're telling the world it's a reproduction.

Item description from the seller

 

I needed a gasket for my original oil fill cap for my Datsun 620. The original part number 15270-78500 is now discontinued, so I looked at a picture and took some measurements, then made my own. Maybe someone else needs one too!

 

My part number here is 15270-78501 to denote a variation of the original part.

 

I've used this on my truck for a couple weeks so far with no issues.

 

Made from Overture brand TPU. This should work for any vehicle calling for the original part number with the original cap. I tried to select all vehicles based on what NissanPartsDeal says these are supposed to fit.

 

If using the elephant logo cap, the ridge goes into the cap, but the Nissan lettering cap, the ridge should go towards the valve cover.

 

Feel free to contact me with any issues, suggestions, or requests!

Edited April 19, 2023 by Zed Head

[Yarb]

Sometimes you have to bite the bullet  and get an original. Not sure what MSA has but can’t go wrong.

[Zed Head]

You probably meant ZCD.  MSA has nothing.  

Who knows what "new" means.  The cheap one looks like a hardware store flat gasket.

https://zcardepot.com/products/oil-cap-gasket-seal-oem-240z-260z-280z-280zx?_pos=8&_sid=583fc178d&_ss=r

https://zcardepot.com/products/oil-cap-gasket-seal-240z-260z-280z-280zx?_pos=5&_sid=583fc178d&_ss=r

A person could probably find something that would work on the old internet.

https://www.mcmaster.com/products/gaskets/

[Yarb]

@chaseincatsmentioned the zcar store earlier in the thread. I checked ZCD when I saw the thread. Didn’t find a replacement. I bought one, have to go back and see where I found it.

[Zed Head]

On 4/18/2023 at 11:08 AM, chaseincats said:

thezstore has replacement seals, you're just paying 20 bucks shipping for a 2 dollar piece of rubber

I looked but did not see anything.  Tried all of the words - seal, gasket, filler, oil...  Got nothing.

Edit - I tried again, working my way through their new website sub-menus and finally got to the secret link.  Wrongness and unavailable.

 

Gaskets and seals > Oil cap > o-ring

https://www.thezstore.com/category/552/gaskets-amp-seals

https://www.thezstore.com/category/789/oil-cap

 

Edited April 19, 2023 by Zed Head

[SteveJ]

3 minutes ago, Zed Head said:

I looked but did not see anything.  Tried all of the words - seal, gasket, filler, oil...  Got nothing.

It's listed, but it's unavailable from MSA. https://www.thezstore.com/product/4919/oil-cap-o-ring-72-83-zzx

[chaseincats]

Arg 

I wonder if I am able to get the old one out, if I can just take it to home depot and says 'what fits in here'? haha