first happy thanksgiving to everybody, I do have one question maybe someone can answer. I have been chasing exhaust fumes which really are not that bad, but the wife still smells it. on my rear deck I have the large weatherstrip that's been installed years ago but I was missing the small one that I call the part where it goes the rain gutter. Nissan part is a 3-piece weather strip. the one msa sells made by precision that is a 1-piece weather strip that glues to the top channel where the hinges are and down the 2 sides. I really do not know what is does, is it meant to keep water out of the channel or is for exhaust fumes? thanks

It's there strictly for water management (by design, it can't contribute to sealing off exhaust gases from the cabin because covers only the top and sides of the hatch opening, while remaining completely open to the outside at the bottom).

If your Z is a later-model 240 (where there are no vents on the lower hatch surface), the most likely culprit will be your main weatherstripping ("the large weatherstrip that's been installed years ago"). It may have lost some of its original shape after years of living 99% of its life in a crushed state while the hatch is closed. IIRC, some owners also found that the gasket around their taillights housings had deteriorated, allowing exhaust gases to enter the cabin through the rear panel.

If your Z is an earlier-model 240 (vents on the lower hatch surface), that's a whole different (and more challenging) ballgame. There are several threads on the CZCC site that discuss problems (several) and remedies for this design.

Edited 5 hours ago5 hr by Namerow

my z is an early 260z, and I did check the main weather strip using a dollar bill that will not slide at all around the hatch. I did change the taillight gaskets but is did very little to help. I could not understand why Nissan did use that seal for water management as the water will only run down the back anyway. maybe is it designed to keep less water out?

1 minute ago, kully 560 said:

my z is an early 260z, and I did check the main weather strip using a dollar bill that will not slide at all around the hatch. I did change the taillight gaskets but is did very little to help. I could not understand why Nissan did use that seal for water management as the water will only run down the back anyway. maybe is it designed to keep less water out?

I am going to change the door seals that I did use years ago that are made by precision to the s30 world door seals that I already ordered. it will let my doors close tighter as the precision makes them stick out a little. it can only help when the windows are closed anyway, but with the wife anything will help. she does not understand it is a 51–52-year-old car with no catallactic converter.

Also check the vent hose seals from the fuel tank where they come through the floor. The grommet at the license plate light where the wires pass through the rear pan. The seal around the filler neck and the grommet at the drain for the radio antennae

Don't forget the 2 rubber plugs underneath the back side of the hatch...

thanks for all the help, I did install the 2 rubber plugs underneath the back side of the hatch last year as it must have been an oversite when I restored the car years ago, it did help big time. never thought to look up after the bottom hatch was painted and installed. thanks for making me look again at the license plate wire grommet which was replaced back then. years ago, I think back in the 90s I did purchase a black rear carpeted 6x9 speaker box from motorsport auto that replaces the back cover for the taillights. what I just found was the bass tube in the center has an open 2" plastic pipe that lets the bass out from behind the 6x9" speakers into the cabin. so, I used some black gorilla tape and closed up the pipe on the inside. if it does help which I now think it will then I don't mind losing some bass and having better air in the cabin. that weatherstrip in the rain gutter seems useless to me maybe that is why I never replaced it back then. but it was cheap enough that I will just replace it, so it is original.