Datsun Roadster Forum-311s.org

OK let me explain what is going on. I have been helping a friend get his 1600 back on the road last fall had it going pretty good after new brakes wheel cylinders new tune up new starter and fixed some electrical problems, cleaned out fuel tank adjusted valves and carbs. Now when I try to start it spits will not idle will not run. Drove it last fall and was running pretty good now it will not stay running. I thought maybe carbs were messed up so I had some spare carbs and tried them same problems. Timing is on firing order ok getting fuel to carbs just will not run. I am out of ideas any advice would be very helpful.

Check compression just to be sure there isn’t a stuck or tight valve.

Check the condition of the points, rotor & cap. 12v getting to the ballast resistor? Clean, tight connections? Coil primary polarity correct?

Did you synchronize the carbs? Air leak? Is the fuel fresh?

Peace,
Pat

I put in new points condenser plugs cap and rotor will check ballast resistor and compression I do have a feeling it is in the electrical somewhere

Just because you replaced those parts doesn’t guarantee that they aren’t defective. Try swapping some of the old parts back in.

Habitat.pat wrote: Mon Jun 14, 2021 8:23 pm Just because you replaced those parts doesn’t guarantee that they aren’t defective. Try swapping some of the old parts back in.

That's a good Old School rule ! Undo what changed; if you already threw it away then replace again and pay extra attention to the settings.

Basic 3... fuel, spark and compression. I suspect spark, so check it with a timing light or screw driver in the plug wire. But you also said "it won't STAY running..." does this mean it runs but won't rev up? If intermittent spark I would suspect the points condenser or gap. If no spark check the rotor too.

I can only get it to run at high rpm and rough at that then it dies

Sounds like a fuel issue to me. Are you getting good flow to the carbs? Could have gunk in the float bowls or an orifice partially blocked.

What do the plugs look like when it has just had a high RPM run?

Do you choke it ? When it starts to die and no help ?
When it quits is it abrupt? Or stumbles then quits
It starts right up and idles or medium throttle at 1st ?.
Are the slides free, no carbon tracking in the cap ?
Wire arcing , fuel is new , runs even & smooth part time ?
Centrific weights move free ? Distributer shaft bushing tight enough ? Might try new plugs possibly fuel fowled

Put in new 93 octane fuel new plugs it starts very rough till i can get it to high rpm choke makes no diff The plugs are new and when i pull em they look black like too much gas. I am going to try again Friday. The thing that confuses me is I had it on the road last year and was running pretty good, now just spits backfires about to go crazy on this one.

Check firing order, 1,3,4,2 counter clockwise... might have crossed a couple. If the plugs are black it's either not firing the fuel or its totally flooded which you would likely see and the carbs will not BACKFIRE out the carbs unless they're lean, but they will "snarf" or sneeze... since it will run at high rpm I'm thinking you crossed plug wires...