Stalling issue(under throttle)

[NA&CH]

@Captain Obvious I purchased the z with a "msa" header and straight 3" bent metal... car was obnoxiously loud. Car ran and drove perfectly fine. 45min cruises no issues at all in FL. I did have always a half to full tank. I never really got into the throttle say to redline yo see if I had any sputter or missing of sorts. The car was to loud. But this issue would have definitely been felt. 

I purchased a Zstory exhaust and had that installed. Changed nothing else besides the exhaust. When the car returned i took the car out for a test sound drive. First to second then i roll into the throttle once i got past 4k the car started to sputter and would shut down the tech would jump fuller redline to 0 back to rpm. Then idle fine. I u-turn do the same thing and the c Ir shuts off and does not turn over. Eventually when cooked down it started up idled ok. The car had a 1/4 or lower. Closer to 1/8 tank. I then replaced the gas filter after the fuel pumps out back. 

I drove into the carb cleaning and now cant di anything until my gasket arrives. 

Vacuum seemed fine; compression 170-180 across the board. 

I did notice before pulling the front carb off that when I would blip throttle there was no suction. I adjust the mixture screw(behind dashpot by connector rod) before I knew the adjustment screw below. Never did do a test drive before the gasket broke on the float tank. 

Mechanic also said the float angle was way off. 

Hope this helps helping me @Captain Obvious

Thank you all for the help,

Chris

[NA&CH]

I emailed Ztherapy. The carbs are theirs from 04. I was seeing if they had anything new done or just another rebuild in the future.  Spoke with Pam. 

 

Chris 

[heyitsrama]

So what’s the status? it seems that you needed to align the jet, and then set the float level...




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[Captain Obvious]

On ‎7‎/‎27‎/‎2018 at 5:58 PM, NA&CH said:

i took the car out for a test sound drive. First to second then i roll into the throttle once i got past 4k the car started to sputter and would shut down the tech would jump fuller redline to 0 back to rpm. Then idle fine. I u-turn do the same thing and the c Ir shuts off and does not turn over. Eventually when cooked down it started up idled ok.

If the tach is jumping around when the problem is occurring, then the problem is electrical in origin (ignition), and has nothing to do with the carbs.

It unfortunately sounds like you may have created some more work for yourself by diving into the carbs. Don't get me wrong though... I wouldn't be surprised at all if there were some gains to be had by working on the carbs, but it sounds like the main problem that got you here looking for help in the first place has nothing to do with the carbs.

And, also unfortunately, the carbs are like genies in the bottle. And you've let at least one of them out.  Now you've got torn gaskets, misaligned needles, at least one malfunctioning suction piston damper, and unbalanced carbs.  I'm so cheery to have around, aren't I?   

Don't worry. There are lots of people here on the forum who won't rest until you're back on the road. When you get your new gaskets, try to get everything back together and see what happens. Have you ever measured the float bowl level?

Did @Bruce Palmer ever get in touch with you to help you with the needle alignment requirements?

[Stanley]

On 7/26/2018 at 7:09 PM, Captain Obvious said:

Using sandpaper to remove even more material from needles that already have unintentional material removed from them probably isn't going to help.

To be honest, I'm a little lost on exactly what problem it is that your are chasing... Can you restate the problem you are trying to fix? Maybe a fresh start will help.

Looks like the pitting is at stations 1 & 2 which are in the idling zone.  Polishing the needles only in this area will make it richer at idle which will foul the plugs unless the mix nuts are raised, and that will make it too lean at cruise and top end. According to the "Just SUs" book (and common sense), modified needles must have an even taper.

According to official SU publications, modified engines (they include engines with only a change to air cleaners or exhaust system) require non-stock needles. The publications refer to British SU's for which there are a variety of needles to choose from. Nissan didn't supply alternate needles for the Hitachi's as far as I know. Modifying needles is easy enough I guess for Z car engine builders and race mechanics (I saw one with 40 years experience leave with stock needles and bring them back 5 minutes later after modifying them) but for me it's an all day job, with lots of note-taking and micrometer measurements, followed by road tests, and it's still a bit iffy.

[NA&CH]

@Captain Obvious nothing from ztherapy. I called and spoke with @Bruce Palmer and he told me to call Steve. The number for Steve just rings. Oh well. 

I am lost. I received the gaskets for the float bowl. Installed and no leaks. Also no fuel flowing from the velocity stack. So 1 thing I think may be fixed. The level. I'll have to check that. I blew into the fuel line and played with the float bracket so it would be parallel with the top. All items work here. The pin there is no leak or something stuck. 

I did notice nothing changes when I take the vacuum hose off of the distributor. I also read try blowing into the distributor through the hose. Nothing moves and the engine does not change idle, die nothing. 

The car will not start with 2.5 turns down from the adjustment screw. I had to go to 4 turns to get it to start and idle. 

I feel the car is working on the back 3 and that is all. I have in my possession a flame thrower 1.5ohm and the electronic spark parts. Should I change those out and then start playing with the carbs?  

I also purchased a new balance bar bc my OEM one was missing the spring screw on the front carb side. Originally zip tied together. And looks like the new one with the screw is no different. I am missing something here. 

Anyone want to sell me a Just SU video? I am looking for the white towel emoji.... 

Thanks all again,

Chris

Oh and I have something pulling power enough to kill off a brand new optima redtop battery....

[Zed Head]

If it was only running on three cylinders you'd probably know it.  Although, apparently, three cylinders are almost as smooth as six.  But that would be half power.

The ignition parts probably won't help what you're describing.  And the distributor vacuum is probably on ported vacuum so nothing will happen at idle if you disconnect the hose.  And you would suck on the hose, not blow on it, for a test.

You might start over with a new description of what's happening now.  You started with what sounded like a possible ignition problem, then you got in to the carbs.  Not 100% clear what problem you're trying to solve. Might be blending two or more together.

[Captain Obvious]

I would change as little as possible and work on one thing at a time. Don't put in any other significant parts (like a new coil) until you have a handle on where you are now.

Someone please lend this guy a copy of the just SU video? 

Any kind member in the Naples, FLA area that can lend a hand?

[siteunseen]

On your power pull, charge the battery then unhook the alternator and see what you have the next morning. 

 

[heyitsrama]

Going down 4 screws in order to get a start is an indication that the float level is out of adjustment. Although you have set the parallel adjustment, the middle lever should be adjusted too. From the top portion above the float (not the lip, rather the plane that makes the edge) set the distance to close at 14mm, I do this by blowing air into the float needles, and adjusting the float till I hit the point, measure, and adjust.

Once you have this established you should be able to get the tune back to being around that 2.5 screws down.

We’re are you located, maybe there is someone around that can give a hand. [emoji41]


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[Captain Obvious]

6 hours ago, heyitsrama said:

Going down 4 screws in order to get a start is an indication that the float level is out of adjustment.

That's too general. There are lots of things that could cause a necessity to run four turns down.

And now that the floats have been "rough set" using mechanical means, the only way to truly be sure the level is correct is with a clear tube to actually view the bowl level. Everything else is just a guess.

6 hours ago, heyitsrama said:

We’re are you located, maybe there is someone around that can give a hand.

I think that would be the best thing... His location is near Naples, FLA.

It would be great if there was a kind forum member not too far from there who was willing to stop by and lend a hand!

[NA&CH]

Thanks a bunch for the ideas and tips guys. I have my auto mechanic(electrical) going to search the power pull this weekend.

One of the very first comments was that the electronic parts I had could by my issue. I know I opened a "can of worms" with the carbs but if there is not enough spark getting to the sngine could that cause anything with the carbs? Typing this and reading  makes believe I know that answer... Just typing out loud.

I'll look up float bowl adjustment. And check things off...

Any YouTube watches I should look at? 

Chris