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After 8 years ...


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...it's finally out of the garage


I’d say the majority of the restoration is done. Of course it's never really done, but


Body buffed and waxed:





Engine bay cleaned up:



Interior restored (obviously not to stock):



It runs OK but having some fuel delivery problems. When I hit 3rd gear and 35mph it starts bucking and wants to die. I see a constant stream of air bubbles in the glass fuel filter.

If I run it out of a gas can under the hood, I smoothly hit 50mph in 4th gear no problem (albeit slowly). Although it does only get 3mpg and I don’t see any leaking. Seems like it would smoke like a chimney burning that much fuel.


Here is the only question I have for the group;

During the fuel troubleshooting process, at one point I thought the fuel pump had stopped working (in hindsight I think it was vapor locked because of the hot day). So I ordered a new one from RA, installed it, then discovered this new one truly was not pumping. I removed the valve cover and saw that the pump arm was too short and horizontal – placing it under and beyond the camshaft. The arm was definitely different than the one that was on the motor. See pics


Old one installed:



New one partially installed:



Comparing the two:



Finding this hard to believe I contacted the manufacturer (USMotorWorks) to help solve the mystery.

They responded after some research but only told me that they have sold these for years without such a problem.

Any ideas? Do I have a non-stock camshaft or the eccentric is not installed correctly?

I would like to make the new one work as it looks more original (with the screws on top). The one that came with the motor doesn’t look like that, but it works!




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Air bubbles are a crack in a hose or loose hose clamp somewhere between the pump and the gas tank. Air is easier to suck in than pulling gas up from the tank.




Compress and move pump arm to the left and up onto the eccentric as you mount the pump. Then tighten the bolts. This one was just put on wrong. Eccentric look fine




Bottom one is an after market pump so not really a good comparison.


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both are aftermarket pumps.

the brass top one has been sold for years and they work ok but I never used them. I puill them off and find a Japan unit myself. Only in a pinch I have used them.Made in Mexico was the one I had.

the other is a close Chinese clone which look good like the orginal.


I have 2 in box but never ran them.  A few people have said the pump arms or the spring or picel point fall apart.


as for vapor lock I havent seen this happen to my self. if true loosen the gas tank cap a bit if you think if thats it.


as Mike said install the pump make sure the arm runs the the oblong shaped eccentric  push on the arm while installing to engage the eccentric. If really too short to engage this then something is wrong. Wrong arms installed from factory is all I can assume.


You said 3 miles to a gal? Is this correct????? or you forgot the 1 on front of that 3 ?    like 13. even that one aI dont believe on a 2wd truck

choke ON ,float set right?




Edited by banzai510(hainz)
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3mpg that's correct. When I ran it from the (1 gallon) can, it sucked that down 1 1/2 times around the park, 3 miles. It will suck down that can in 10 minutes just idling.

Looking in the window on the front of the carb, the gas level is in the middle of it.


I think it is possible to install the new pump if I rotate the camshaft so to be farthest from the arm, and I manually push the arm in/up. But in this condition the arm is already compressed and if I then ran the engine, either the arm or the eccentric would probably be damaged. The old pump installed perfectly without that rigamarole.

I'll return that pump to RA (hopefully). In the future, any reasons to not go electric?


Yeah, redone 240Z seats - new foam and covers, some black touchup paint. Trying to get the mounting right was a learning experience.



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The gallon of gas is in the fuel tank!!!!!!! You have a return line. The gas from the can was pushed back into the tank through the return line.





That pump arm isn't compressed. At rest it should be fully down. Give it a strong push upward. It's a strong spring needs a strong push. It will fit onto the eccentric.


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Mike caught that one as the gas went to the gas tank via the return line.

My 510 dont have a return line so when the carb is full the needle valve will shut the gas off. the fuel pump when not running you pump by hand once carb it full the pump will go limp stop pumping.

With return lines I assume they still pump as the extra gas is pushed passed the carb entrance and is returned back to the tank.


make sure you use the spacers betweem the pump and head and just squeeze the pump and arm on there,

you could turn the motor over so eccentric is farther away from the pump.

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I had an F250 with dual tanks. The front tank pump died so I figured I'd just run the rear for a while. Worked great until I realized the check valve in the front tank pump had gone out with it, so after a couple short drives the rear pump just filled up the front tank and started overflowing it 😂


/unrelated story

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If my fuel gauge worked maybe I would have noticed. Probably not.


By the way, I have some parts left over someone might want; some duplicates, some parts that were replaced by better ones, and – probably of most interest – I have an NOS tachometer. I decided to go with the $150 SW tach after reading some posts. The Nissan tach I have looks like new, still with its’ box. I bought it years ago on ebay (when they were more affordable). I didn’t test it. Don't know if it's for the older or newer model years. Other parts include L&R door rubber gaskets, windshield gasket, bucket seats (Nissan but not 620), ash tray, inner seat belts [receiver], misc stuff. See pictures.

I guess I'll advertise these in the classified section, but I wanted to give first dibs to those who responded to my post.





Tach pics












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  • 3 weeks later...

Well, I've started the process of pulling out the tank (to clean and check the non-functioning level sender), checking all rubber hoses (I can see the PO did not put things back together correctly), and... going with a new electric fuel pump by the tank. I fabbed a delete cover plate out of 1/4 SS and will also mount a regulator/pressure gauge on those same studs. Is all this necessary? No, but it's fun!

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I've heard that the small block chev block off will work too.




Above all Z20E, Z22E and Z22S 720 engines with electric fuel pumps had this block off plate that is a perfect fit on the L series engines. But kudos for making your own!

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I'm sure you know this, but a single electric pump needs to be as close to the tank as possible and as low as possible. Supply good voltage to it using a large gauge wire and good grounds. Probably best to have it on a relay too so you're not drawing high amps through a switch.

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Mounting close as I can get to the tank and still be able to plumb it.

I chose 16AWG wire, should be plenty. I was planning on running it through a switch under the dash. The one I had laying around isn't really heavy duty but I thought surely that pump would only draw around 1 amp. I guess I could add a relay.

Thanks for the input.

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