Hello, i bought a 71 datsun 240z that has a l26 with i believe su carbs on it, and a 5 speed in it. I noticed today that there seem to be a couple of vacuum hoses that are either just open or plugged, i took some pictures to see if it helps someone figure this out. I hooked up the vacuum control on the distributor but really didn't notice any difference in the change of idle. The car is idling between 1000-1200rpm's after warm up, im not sure if thats normal or not. Also the car seems to be running really rich. also, is there a good manual that i can buy for this car that someone can recommend. Thanks for the help in advance.

Thanks,

Albert

Edited October 10, 201212 yr by 03redzo6

First of all, welcome to the club! Secondly, check out the SU-carbs section in this forum and use the search function, there is tons of info here for you to find. It seems you are missing the tube from front carb to distributor, it suppose to be attached on the manifold side of the carb. Other 2 tubes from the carbs supposed to be attached to original style airbox.

Btw. you have exactly the same coil as i do

Hi Albert.

Koalia is correct. There should be a vacuum hose from the inlet manifold to the distributor.

Where does the hose in the last picture come from? If it comes from the inlet manifold, then remove the bolt, and determine if there is suction there with the engine running.

If it doesn't, then attach a hose from the unused fitting near the centre of the manifold to the dizzy.

Idle should be 7-800 RPM or thereabouts.

Haynes put out a good book---DATSUN 240z & 260Z OWNERS WORKSHOP MANUAL. Lots of good reading there.

Your engine has carbs from a 240Z, which will run well. Someone has swapped in a 260 and put 240 carbs on there. Originally 260 was fuel injected.

Hoses from the carbs are merely breathing tubes, and as Koalia said were plumbed into the air cleaner box.

Tie them away from the exhaust, and shorten them a bit if you want.

Brian.

Edited October 10, 201212 yr by olzed

The 260 was fuel injected? I thought it had flattops?

Nz .

The 260 was fuel injected? I thought it had flattops?

The US 260Z used flattops. It was not fuel injected from the factory.

There were two different 260's in North Am. Early one with flat top carbs like 73 240 (though not identical), skinny bumpers with hydraulic shocks, and then a later one with FI like 280 and bumpers like the 75 280. The interiors for both were the new 280 style dash and console. Real Heinz 57.... No wonder folks restoring 260's have a devil of time finding parts for them!

Nice Z BTW. I like the red wire that comes through the firewall at the choke cable grommet and goes to the coil best. I'm pretty that's not stock... and worth understanding what it bypasses (like the ignition switch....).

Edited October 10, 201212 yr by zKars

We sell a dvd that will help shorten your learning curve on the Hitachis (SUs made under license for the Japanese makes). You could for very little money go through them, clean 'em up and get them running in some known state to see what you really have.

JUST SUs ZTV09 for twenty five of your hard earned dollars.

Whatever you do don't plug the hoses that come off the top of the float bowl lid. Those need to be open to the atmosphere. Is there anything hooked to the vacuum advance canister on the distributor? Are you running a points distributor of and electronic distributor. If you are running an electronic distributor and there is no vacuum advance hooked up at the canister it may be because the EI Dist was over advancing with vacuum hooked up..

There were two different 260's in North Am. Early one with flat top carbs like 73 240 (though not identical), skinny bumpers with hydraulic shocks, and then a later one with FI like 280 and bumpers like the 75 280. The interiors for both were the new 280 style dash and console. Real Heinz 57.... No wonder folks restoring 260's have a devil of time finding parts for them!

Late 260Z in the US still had flat tops. Not FI. That was actually the probable reason for the late 260Z - the fuel injected L28 wasn't ready yet, so the late 260Z was the rest of the 280Z package but still using the carbed L26.

Download the FSM from the "Reference" section of xenons30.com, everything you need is in there. The Haynes book is woefully underwhelming.

I prefer the FSM over the Haynes manual.

Europe, Aus, NZ and South Africa never saw the 280Z. They just went further with the 260z and FI until the 280ZX. The 280z came out to try to combat the extra weight due to the heavy bumpers and the tougher emision regulations in CA.

The 260 was fuel injected? I thought it had flattops?

Oops, late night brain fade. I was thinking of the Fairlady 2000 JDM private imports we got down here. I have seen flat top carbs and fuel injection on them.

Depending on the year I suppose.

I actually got up at 1am to try to edit that, but was unable to connect. More brain fade perhaps.

Edited October 10, 201212 yr by olzed

Arne, thanks for the clarification. All 260's were flat top carbed. No FI. thanks!