TiP
when removing the second stage diaphagm you will find a check valve ball
& spring,remove these parts,but hang on to them.
The second stage will come in earlier with quicker throttle responce.
fuel economy strangly enough, improves slightly.
In rare cases if the throttle hangs,tighten the long return spring a tad.
we started this mod at dealer level in 1970
510 carb help!
- bertvorgon
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- Joined: 04 Aug 2003 20:45
- Location: White Rock, B.C. Canada
Re: 510 carb help!
Baz, that is funny, we also did that. I guess it just shows that no matter where in the world one is, we are always thinking of how to get a performance edge.
During Our DATSUN RADIAL CHALLENGE years, we also cut the float to almost a third of it''s depth. This helped with fuel starvation on long and hard right turns, specifically a sweeper at our local race track, where the both primary jet would get uncovered, and the g-loading would shut the float off.. The increased volume of fuel helped get it past that few seconds of starvation. I used this for a few years solo'ing, till I switched to the center hung Weber 32/36..problem solved.
During Our DATSUN RADIAL CHALLENGE years, we also cut the float to almost a third of it''s depth. This helped with fuel starvation on long and hard right turns, specifically a sweeper at our local race track, where the both primary jet would get uncovered, and the g-loading would shut the float off.. The increased volume of fuel helped get it past that few seconds of starvation. I used this for a few years solo'ing, till I switched to the center hung Weber 32/36..problem solved.
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan
Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
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- Posts: 33
- Joined: 06 Apr 2009 21:33
Re: 510 carb help!
okayfine wrote:This, I don't know what it is.72peagreen510 wrote:the DAT512 Carbs?
That's what's on the side Hitachi DAT (I assume for Datsun), 512. I don't know what it is either!
Re: 510 carb help!
OKay, so its been a year and i have lived with this problem. so heres the problem i guess. when i go full throttle either driving or doing it manually on the carb, the flap for the secondary doesn't move. so any ideas? i have also noticed that i have low vacuum. so i guess i just have to figure out where my low vacuum is coming from.
- bertvorgon
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- Joined: 04 Aug 2003 20:45
- Location: White Rock, B.C. Canada
Re: 510 carb help!
Did you ever remove the secondary diaghram, and check that it actually works? It takes all of a few minutes to do, and is the only way to make sure the diaghram is ok.
Low vacuum? What constitutes low vacuum for you? A large cam can cause low vacuum, valve adjust REALLY out..kinda.
Low vacuum? What constitutes low vacuum for you? A large cam can cause low vacuum, valve adjust REALLY out..kinda.
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan
Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
Re: 510 carb help!
yeah i tore it down again last night prior to writing this up. Its all there and looks good. I am going to take the spring and such out today and see if that helps at all (shouldnt really). And the engine is all stock.
- bertvorgon
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- Joined: 04 Aug 2003 20:45
- Location: White Rock, B.C. Canada
Re: 510 carb help!
BUT.....did you test the diaghram? You have to get a small rubber hose, hold to the hole on the diaghram ( tightly), and SUCK! It should pull the arm on the diagram...and hold it ( as long as you keep the seal tight). If the arm does not move, then there is your problem.
"Racing makes heroin addiction look like a vague wish for something salty" - Peter Egan
Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
Keith Law
1973 2 Door Slalom/hill climb/road race / canyon carver /Giant Killer 510
1971 Vintage 13' BOLER trailer
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Re: 510 carb help!
It's hard to trouble shoot when good advice is given and even if followed, it's not acknowledged properly.sac510 wrote: Its all there and looks good.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
Re: 510 carb help!
okay thanks i will try that tomorrow and see how it holds.