Ethanol fuel and limited-use Datsuns

[austinc]

Hi guys- this is a combo general and 240Z-specific post so apologies if it's in the wrong category. After I spent a few hours trying to get my 240Z started over the weekend, it reinforced how modern fuel and Datsuns/old cars that get limited use are a bad combination. And I need to drive my Datsuns more!
My electric fuel pump that was just a few years old was leaking, but I chalked that up to the cheapo Amazon pump I bought. After I replaced that electric pump with a new (different) cheapo one from Amazon, the rear SU was still not getting fuel. I then pulled the carbs off and both needle valves were pretty sticky with old fuel residue. The jet nozzles at the bottom, which should slide up and down when you pull the choke, were basically stuck shut too. I've ordered a carb rebuild kit and am now cleaning and rebuilding the carbs (Randy I have read about your float tool and would like to order one when available). I hadn't started the car in a little over a year and the fuel smelled a little varnish-y, so I drained the tank and put in fresh gas, along with some Stabil fuel stabilizer. By the way, I had the stock mechanical pump but it started leaking hence the switch to electric, wonder if modern gas eats the internals to those too?
I've read most modern pump gas has a blend of ethanol which is hard on cork and rubber, and to use non-ethanol fuel, but nothing seems to be local to the PHX area. There are also ethanol stabilizers (I ordered some of this stuff too which might help):
https://zcardepot.com/products/fuel-sto ... z-280z-510

And I've read of modern fuels sticking up valve guides- is there any treatment suggested for Datsuns that get limited use?
What do you guys do to keep your Datsuns running well (aside from drive them as often as possible!)?
thanks!
Austin

[Randalla]

Can't answer your question directly, as I try to do my best not to let my cars sit more than 4-5 months at a time. Regarding re-building your carbs and the sticky jet nozzles, I can walk you through that as I've probably done 40-50 sets over the years. Most of the time they just need to be cleaned extremely well (there are some tricks I'd be happy to share) and recalibrated. Let me know when you need a set of Float-Syncs. I have them up on E-bay currently and still have about 20 sets left.

[austinc]

thanks Randy, sounds good, I'm expecting my rebuild kit this week or early next. Maybe I can stop by this weekend if you're around and buy one of your float synch tools and pick your brain for tips and tricks. I got the nozzles pretty clean and have the jets working smoothly, but would value any tips to keep them functioning that way.
thanks!
Austin

[Turboman280]

When they went to oxygenated fuel, I noticed that the pilot jet in my dirt bike carbs would plug with varnish if they sat for more than a month. I started using Sta-bil fuel stabilizer and have not had that problem since.

Of course driving it a couple times a month is a better option.

[austinc]

Thanks Carl, interesting and glad to hear fuel stabilizer helped. Lesson learned for me...add some fuel stabilizer, and drive the car more often!

[Racerx3110]

I'm a fan of Seafoam. Stabilizes fuel and cleans as well, I've had good results with it.

[L320-Dale]

Seems I usually have trouble with my carbs too if I let them sit too much. Especially motorcycles. I haven't considered using Sea Foam for a stabilizer? I may have to give that a try.

Dale

[SCARZME]

I worked overseas for 12 years only getting home once a year normally. Before storing my 240 I would 1) fill the tank to the brim and use Stabil, 2) disconnect the fuel pump and run the engine until it quit, then try and start it until there was no hint of fuel left, pumping the pedal constantly, 3) put the car on jack stands, 4) remove the battery and put it on a trickle charger.
In all those years I never had an issue starting the car when home on annual leave. Bottom line, don't leave ANY fuel in the carbs or pump. Filling the tank to the brim minimizes condensation, the Stabil worked great.