# 1966 Datsun Roadster carb/distributor problems



## zdavison (Jul 10, 2009)

We have a '66 1600 datsun with SU carbs. We are having problems with it running smoothly. It has no power (pick up) and it doesnt reach higher rpm's easily. The distributor is negative 5 degrees of the zero degree mark for it to run. We adjusted the contact points and the valves. Any suggestions?


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## sunnysentra (Jul 24, 2002)

I was just at the pittsburgh vintage grand Prix and was talking to a guy that has a 67 1.6 motor with SU carbs. He told me that to tune these things, you need an airflow meter. Sounds like your floats are sticking in one or the other. I am no SU guy, so I cannot help, but generally, you need to turn the mixture screws and mess around until your throttle is perfect. Hold the thing at half throttle and start turning the screws until it smooths out. 

Try a Datsun Forum or maybe Dave Bexfield at Nissan sport magazine can help you out. Emailto:

[email protected]

Chris


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## pulsar86 (Aug 13, 2009)

I used to have a 1970 Datsun 1600 510 with the twin Hitachi SU type carbs. Most problems are with vacuum leaks or sticking floats. They can be balanced by ear listening to the noise of the air being taken in. Set carb by turning the jet adjusting nuts under the base of the carb.usually the nuts only need turning 1/2 turn either way. You check the mixture adjustment by lifting the piston approx .8mm and if idle increases it is too rich, fix by turning jet nut clockwise. If it decreases when piston held up turn anticlockwise to increase richness. do left then right carby from front.the mixture is right when the engine speed rises slightly when the piston is raised slightly above the .8mm checking height. Hope this is of some help. you really need the manual to go through it step by step.


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## u20builder (Sep 13, 2007)

*datsun roadster carb tuning*

I know this is a little late to help but if you go to sportsimports.ca we have everything you will ever need to know about the function and tuning of your cabs. Just click on tech info then su carbs. There is also wiring diagrams for all the model years there as well.

happy tuning.


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## 68srl (Jun 7, 2010)

Go to 311s.org for all of your roadster needs.


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## Chrissocal (Dec 21, 2021)

u20builder said:


> *datsun roadster carb tuning*
> 
> I know this is a little late to help but if you go to sportsimports.ca we have everything you will ever need to know about the function and tuning of your cabs. Just click on tech info then su carbs. There is also wiring diagrams for all the model years there as well.
> 
> happy tuning.


I went to the web site as directed and the only thing showing is the vin plate.


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## Chrissocal (Dec 21, 2021)

Chrissocal said:


> I went to the web site as directed and the only thing showing is the vin plate.


and now the PDF is there. thanks!


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