Datsun Roadster Forum-311s.org

So after getting the oil changed, fuel tank cleaned out with fresh fuel added and a new fuel filter I'm having a terrible time getting the old girl to start and stay running. A healthy shot of starting fluid gets it to start to fire up but it quickly dies. I know I'm getting fuel to the carbs (there seems to be a small leak) so my next step will be to open up the carb bowls and see if there is an issue in there. The car has been sitting for some time but it did run prior to my buying it (short drive around the parking lot).

I also noticed today that the throttle pedal doesn't move the linkage very much but the cable looks fine (from the linkage back to the firewall anyway) It looks like it attaches to a bar mechanism that I assume connects to the pedal? Is there an adjustment point in that area?

Thanks in advance for any hints, tips or tricks!

Get out oiled up 1st , do a compression test ,
, start it on 1 plug ,if it revs to 4 k and a bearing is dry , you have to pull the engine....etc.
. add plugs after 2 min. Of crank/ running, other problems may surface water pump, valve adjustment, vacuum leaks
Easy to pull the fuel line to check the flow & condition
Carb spray the safer choice

You are on the right track at the bowls, provided that you are correct in having fuel to the carbs. The throttle movement adjustment is all right there at the carb end of the cable. None at the firewall.

Bowls look good actually and clean. Now I just need to replace the gaskets. Tried making one myself, didn't end well but I think I'll try again before ordering the parts.

Psevins wrote: Thu Feb 25, 2021 7:50 pm
I also noticed today that the throttle pedal doesn't move the linkage very much but the cable looks fine (from the linkage back to the firewall anyway) It looks like it attaches to a bar mechanism that I assume connects to the pedal? Is there an adjustment point in that area?

Thanks in advance for any hints, tips or tricks!

This may or may not be the problem. There is a nut 9/16 or 14mm box end fits (don't remember which right now) that holds the accelerator pedal arm to the linkage down on the floor. It can loosen up allowing the pedal to move a bit without advancing the linkage. If loose it is enough to diminish the throttle opening. The slot on the arm is a bit sloppy on the post. Lift the pedal up and tighten the nut and then check the throttle throw. This may solve the problem

Dean

Definitely sounds like a fuel issue to me. You have spark if it is running, and you have the timing close enough to get it running, it just won't stay running. That leaves fuel and Air. Check your valves for good measure, but i think you have something going on in fuel delivery/supply based on your description. Float settings are very important.

Went through the fuel system and its flowing fine to the carbs and into the floats. Just to cross it off my list I checked the spark plugs, they were pretty soot covered so I cleaned those up a bit. Still no dice. I pulled one of the plugs and had an assistant turn the engine over to see if I was getting spark and there was none. Which is weird considering it was firing a little with ether or carb cleaner. The distributor and wires all look to be in near new condition (no cracks or age indicators) My assistant did note that the coil was getting pretty hot very fast. I might be chasing a couple of problems simultaneously.

Make sure your ballast resistor is hooked up properly (wiring diagrams in the 311s Tech Wiki), If correct, sounds like a bad/intermittent coil, From my experience, The coil can be ok when cold, but when they heat up, the coil can open (open circuit). That always made me not suspect the coil...and caused me to waste a lot of time

Psevins wrote: Fri Feb 26, 2021 3:59 pm Went through the fuel system and its flowing fine to the carbs and into the floats. Just to cross it off my list I checked the spark plugs, they were pretty soot covered so I cleaned those up a bit. Still no dice. I pulled one of the plugs and had an assistant turn the engine over to see if I was getting spark and there was none. Which is weird considering it was firing a little with ether or carb cleaner. The distributor and wires all look to be in near new condition (no cracks or age indicators) My assistant did note that the coil was getting pretty hot very fast. I might be chasing a couple of problems simultaneously.

Into the float chambers is good. now you have to determine if it is getting past the float chambers. The easiest way is to take a spark plug reading. If there is gas getting to the cylinders but not running, the plugs will be wet.

I think I will replace the coil regardless (cheap plus this one has spray paint residue on it). When I pulled the plugs they seemed dry with nothing on then except carbon build up. The needles looked good when I had them out but I guess I do need to check for fluid getting from the float bowls. If that's the hangup what's my next step?

A spark gap tester is a super cheap way to acess secondary voltage / amps on any engine KDs $22 also a compression tester ...is a must diagnosing any eng too.
Harbor freight s with a flex hose Works well
What model and year ?
If you are good on both above it's fuel or ign timing

1969 1600

I may have to invest in those this weekend. Any reason for a new toy for the shop!

On a successful note I was able to make my own fuel bowl gasket. The lid of a small play-doh container is the exact diameter of the hole in the gasket!

This will do till I get the rebuild kit.

Psevins wrote: Fri Feb 26, 2021 5:09 pm I think I will replace the coil regardless (cheap plus this one has spray paint residue on it). When I pulled the plugs they seemed dry with nothing on then except carbon build up. The needles looked good when I had them out but I guess I do need to check for fluid getting from the float bowls. If that's the hangup what's my next step?

Do you have gas spilling out of the open bowls when cranking?