Confused about original parts numbers change....

[richard1]

I received from Courtesy Nissan a OEM rear hatch inner weatherstrip for the 72 Z.

The new OEM part number from Nissan is labeled 76912-N4500 (part received from Courtesy). The original part number in the NISSAN parts book is 76912-E4100.

Furthermore and where I am confused..... the rubber extrusion from the part received from Courtesy is not shaped as the original one on the car.

My parts catalog is the original 70-73 NISSAN.

Is somebody can explain me why the second section of the part number doesn't match the original number going back to original NISSAN data? There is no superseded part number in the original parts book.

Is it possible that the new parts reproduced as OEM are now generic to fit ALL the S30 models?

If I proceed and install this part, it will not fit. The rubber lips going over the body edges are very large and deep, they are wider than the original and they would exceed the sitting surface on the body (inside and outside) of the actual weatherstrip after installation.

I am also bugged by the fact that the original weatherstrip has not shrunk and fits well all over the inner body.'

My factory original parts book is from 1970-1973, updated June 1974.

[hls30.com]

...

Is it possible that the new parts reproduced as OEM are now generic to fit ALL the S30 models?

...

Not possible, and absolute certainty on the part in qestion!

Will

[Arne]

Not possible, and absolute certainty on the part in qestion!

Will

You meant not impossible, didn't you, Will?

[hls30.com]

Arne, No, there is a silent "just" that my brain inserted secretly between the "Not" and "possible", that my fingers chose to play havoc with by not typing it!

Will

[richard1]

Arne, No, there is a silent "just" that my brain inserted secretly between the "Not" and "possible", that my fingers chose to play havoc with by not typing it!

Will

.....I hope you understand what I said.

[geezer]

Is somebody can explain me why the second section of the part number doesn't match the original number going back to original NISSAN data? There is no superseded part number in the original parts book.

If the supercession took place after your parts catalog was published it will not be seen in your catalog. I will look it up in the microfiche to see what changes were made after June of '74 up to the microfiche date of issue. I know you are getting frustrated trying to source this weatherstrip, but I don't know if it is possible to find one identical to your original today or not.

[Arne]

Richard, I did read all of your post. Most of what you ask seems somewhat rhetorical to me. You are surprised that there may have been further supersessions after your copy of the parts list was printed 35 years ago. This surprises you -- how? The attached screenshot shows that the part number you are working with now WAS superseded by the time my copy was published in December 1979.

[geezer]

There you have it. Thanks Arne...saved me lugging that machine up from the dungeon.

[Arne]

Is Nissan making some parts more generic these days in an effort to cover all S30s with fewer part numbers and inventory? Yes, count on it. Are those parts going to be exactly correct for those of us who want to keep our cars as original as possible? Nope, they won't. This is a problem that most of us have already had to deal with at some point or another.

Take original shift knobs as an example. I have a brand new one from Nissan for my car, but it is noticeably different than my original. So much so that I have the replacement in a drawer in the house and still have the slightly flawed original on the car.

In this case, I suspect that the original supplier to Nissan is no longer in business, and Nissan had to find a substitute manufacturer for these, who saw some pictures and specs, but never saw an original in person.

In sum, I feel your pain, really. But complaining and grumbling to us here won't help, as we are all in the same boat. You could complain to Nissan, but catering to a few people buying low volume and low profit parts isn't going to mesh well with their goal of making profits and staying in business.

[bobc]

Arne,

Funny you bring up shift knobs. My vintage car had one of the new ones on it and it never felt right! The second I went to shift I could tell the difference between the VZ and my 1970 with an original knob. I found several other items that changed over the years on the VZ as well. I guess over the years, vendors change, spec change, materials change, etc.

Bob

[hls30.com]

...

Is somebody can explain me why the second section of the part number doesn't match the original number going back to original NISSAN data? There is no superseded part number in the original parts book.

...

Ok,

The first section of the part number is to indicate fitment, the second section is actual part given that fitament.

Your '74 parts book was right in '74, since then, there have been umpteen revisions to the parts lists it illustrates, caused by consolidation of similar parts, loss vendors, and to make matters worse, the latest part number is what makes it into the latest parts listing, meaning a superseded part only lists its closest predecessor, and not the however many there have been for the original part number. If you use Nissan Fast to look up your part numbers(the USA version or the Japanese versions anyway), it will normally list the entire supercession chain-most parts people will not share that with you by default, but it is there. Older listings will only show what was current at the time it was published.

I have several version of the parts catalogs, and this is just the way it is...which is why I have collected several of the carts catalogs, Microfiche, and software, sometimes a partnumber has to be found by exploring several layers of Nissan part numbers.

Will

[Carl Beck]

Nissan as well as almost every other manufacturer - supplies "replacement parts" such that owners can keep their cars operational for extended life cycles. Manufacturers do NOT supply parts with the intention of providing exact replicas of the original part.

Why? - because in the manufacturing process, original dies and molds simply wear out. Over time "improvements" are made that either reduce the costs of manufacturing, or increase the quality of the part. As mentioned, different vendors with different dies/molds etc can supply the parts to Nissan as well over the years.

If the form, fit and function of a part produced later, is the same as the part produced earlier - and both come from the vehicles manufacturer - then the newer part is considered to be an OEM "replacement part". Appearance is similar, but need not be identical as far as the replacement part supply is concerned.

If you want an exact duplicate of any part - you have to find someone that has the exact part as New Old Stock. Only the original, exact part should be labeled NOS and the original Part Number should be given. The rear hatch seal supplied by Nissan for a 280Z is NOT NOS for a 240Z - it is however an OEM replacement part for the 240Z.

Because of massive misuse - the term New Old Stock has become almost useless today.

FWIW,

Carl B.