Someplace in these forums we recently discussed the kidney tanks on early 240Zs. I can't find that Post now, but I made an interesting observation while visiting Clive (EVIL-Z) this week so I'll Post it here.

Clive is carefully dismantling February 1970 240Z #01905. The car is original and has never been apart before.

When he pulled the plastic cabin panel behind the passenger seat, he discovered his car does NOT have a vapor tank. My own #02807 (Apr/70) didn't have one, either.

Clive's car has slightly different vapor hoses under that panel than mine had, and his fuel tank had one less vapor hose attached to it than my car did, made only two months later.

When I dismantled Sep/71 240Z #43421, I found a metal vapor tank with SIX hoses attached to it. Four went to the fuel tank, one to the fuel filler neck, and another to the engine bay.

So far, I have personally witnessed these "kidney tanks" being manufactured of clear plastic, black plastic, and black sheet metal.
I know John T wants proof of the black metal unit, and as soon as I can locate it in my garage I will post a picture here, with magnets on it.

So basically, I'm pretty much in the dark about what went on under that rear panel in the early cars. It appears probable that Datsun was doing some on-road experimentation with these early 240s, trying to solve some undefined problem which never effected my car when it was new. I never had a tank, and never seemed to need one.

Curiouser and curiouser.

Frank

Frank, I am not questioning the black METAL tank, there are tons of them out there. What I said was that I have never seen a black PLASTIC tank. The early Z did have a white"ish" translucent plastic tank.

The reason they were changed to metal later on was because the plastic tanks cracked and allowed fumes into the cabin.

On another point, my 5/70 build #3833 also did not have a vapor tank installed from the factory. NOR did it have the hard vapor line that ran to the front of the car to the area under the coil. NOR did my fuel tank have an extra "nipple" on the driver side to route a hose to the vapor tank.

I believe the reason for this was the fact that the car was sold in Hawaii, not mainland North America. I think that North American bound 240Zs had the extra plumbing and tank for emissions reasons. I suspect that some early cars destined for other markets were built without them. Shawn's Hawaii car #3862 also does not have the tank or plumbing mentioned above. I spoke to Jim Frederick about this awhile back and he was intrigued, thinking that all 240Zs had the vapor tank system. The fact that the original gas tank DOES NOT have the extra fittings for the vapor hoses verifies that the cars not sold in North America were most likely different and exempt from additional emission parts. I would guess that European and Australian cars also did not have them.

See, you learn something new every day!

_________________
John Taddonio
1970 240Z
1977 530Z
1984 300ZXT
zcarnut@hotmail.com
FB: Zccr zcarclubofrochester

Here are some pics from #1905.

Notice hoses and NO vapor tank:



Also stock tank with ONE fitting for venting:




I have another question about the tank. When did they use and not use the extra tab there to mount an electric fuel pump. My 73 tank did not have the extra metal there for it but like all 240Z cars I have seen now had the wiring in the harness for the pump. It seems backwards that early Z cars have a place to mount fuels pumps but the later 240z cars don't. To make it even harder to trace down, I know of a 6000 mile 73 240z that does have the mount for the pump! I also have a NOS tank that doesn't have it....go figure.

_________________
Clive Bogle President - New York Z Car Club - NYZCC.COM
1971 240Z - LS1/T56
1974 260Z-L30
1976 Fairlady Z

My Apr/70 car has that platform for an electric pump, but so much has happened to my poor little car over the years, I can no longer attest that this is the original tank. I faintly recall discussing an electric pump back in the 1970s, and being told it was a no-brainer bolt-in back then because Datsun had prepared the cars for such a modification.

Thanks for the pix, Clive.

John, I misunderstood what your original question was. Now I gotta go find a black plastic tank to Post here, shown with magnets falling off!

So, aside from the practical value of having a vapor tank to collect fuel fumes, if someone is trying to build a 100-point restoration of an early 240, it's pretty much up to him whether to install a tank or not?

A tough judge would have no way to know if the car had come equipped with a kidney tank or not, even if he got under the car and counted hoses to determine if one had been installed during the restoration ~ is that right?

Clive,

Is the plastic interior panel different since there was no vapor tank??


Joe

The interior panel is not different, it still has the "bulge".....

_________________
John Taddonio
1970 240Z
1977 530Z
1984 300ZXT
zcarnut@hotmail.com
FB: Zccr zcarclubofrochester

As far as I think I know, if it had a smog pump, you have a right Kidney Tank, if not no tank.

Nope. The cars I mentioned above all have the smog pump with the air galley but no vapor tank and related plumbing.

_________________
John Taddonio
1970 240Z
1977 530Z
1984 300ZXT
zcarnut@hotmail.com
FB: Zccr zcarclubofrochester

I'll jump in and stir this pot a bit on the topic of electric fuel pumps. My parts catalog covering 1970-1973 depicts an electric fuel pump in the same section as the mechanical pump. The details show the electric pump superseding the last L24 mechanical pump, but it is for the L26 motor beginning 08/73.

But there appears to be a contradiction: a L26 mechanical pump is effective 08/73, superseded by another mechanical pump on 11/73. This suggests that either type pump was in use concurrently for the L26; there is no mention of a L24 application for an electric pump.

In the next catalog section, the depiction of the fuel tank does not have the tabs for mounting the electric pump. My tank has these tabs just like yours. Go figure!

_________________
Jim Arnett
Richardson, Texas
HLS30-15320 12/1970 (original owner)
ZCON 2015 Gold Cup - Street Modified class

Add-on: two fuel tank assemblies are listed in the catalog, both effective to 07/73. One has the application as "crank & exhaust", the other shows an application of "evapo". The second one is superseded by another model for the L26.

_________________
Jim Arnett
Richardson, Texas
HLS30-15320 12/1970 (original owner)
ZCON 2015 Gold Cup - Street Modified class

Weirder and weirder.

One of those anecdotal stories....I read "somewhere" that running a thin-wall gas tank without proper venting can deform the tank eventually. A visual story even if not true.

I run a plastic tank on my '70 with an active flow valve on the carbs. I capped off the vent on the top of the tank on the muffler side. The Z Doctor in Roanoke suggested that to me in the '80s. So far so good.

_________________
Bryan Little
Datsunzgarage.com

1970 240Z - enhanced F54 L28 w/P90, Weber DCOEs, 4:11 R200, Nissan T5 5-speed

Maybe Carl can help us out on this one, he was also selling Z's back
around that time and his memory is a lot better than mine is. I used to
have a good memory, but I forgot where I put it!

Concerning the electric fuel pump "Texas Jim" spoke of, and the fact that
it is in the same section of the partz manual as a supersession: I am
trying to recall if that was one of the "pieces" of the solution to the fuel
percolation and starvation problem which plagued a lot of the '73's?


BTW the reason for the overlap into the 1974 model year (260Z) was
that the L-Jetronix EFI system was intended to be introduced on the L26,
but there were certain bugs and/or emissions issues that had to be
resolved to qualify for importation. Consequently the SU-Hitachi "flat-
top" carbs were retained to fill in the void until the EFI became ready to
introduce on the 1975 (L28) 280Z's.

FWIW, ~Rick~

Ok, so much for that thought. Here's another, as I look at the tank pictured, are we certain that tab is for a fuel pump Why I say this is, none of the other Z's have fuel pumps attached to the tank, and I have removed over 100 diferent gas tanks and any with external pump was seperate of tank, maybe because of vibration issues. Now to hold a wire in place, many tanks have tabs like that to hold a wire harness. Just some thoughts here.