Datsun Roadster Forum-311s.org

So I'm finally starting to drive my Roadster after 3 years or so of putting it together. Seems to be running pretty good, maybe a little on the rich side if anything, timing is on, valve's set properly, carb's gone through, etc. And it seems kind of gutless. She's got a little pep to her, just not what I expected. It is a smog delete with a smog distributor, can that be part of the problem.

I have replaced the temperature sending unit, new thermostat 180*, hoses, yada yada, flushed the block and radiator several times. Radiator seems to be flowing well, at least with the garden hose flushing through it. It seems to be heating up, the temp gauge slowly rises to the top and nearly gets to the 250* mark. I get it home and start using my thermo gun and it showing between 140* - 170* aiming it at the head, valve cover, carbs, thermostat, sending unit, top and bottom hoses, across the radiator, block, etc. etc. It's not building up a lot of pressure at the over flow tank and seems to run fine. This is all within maybe 20 minutes of driving.

I've always been the type that prefers a cooler running engine for piece of mind.

Any suggestions?

Thanks

I would suggest the distributor is not doing its, new non smog, job. When I had mine looked at it was confirmed that it was never going to allow the car to run properly without being rebuilt. The refreshed unit has been installed and even running in Southern California during the summer months I have had no issues.

Just removing and capping the air injection is only the first step.

As stated above, you want a no smog distributor curve. Certain systems were in place on a smog engine to make sure the car ran correctly and that included some differences that could cause over heating if not working. However, it sounds as though your gauge may not be reading correctly. A typical culprit is the little voltage regulator box located on/near the steering column with two spade connectors. A bad one can cause erroneous readings. If your laser is not showing its hot and it's not boiling out the res then it's probably not, but take your time as you don't want to blow a gasket. Is the sender properly grounded? I think the gauge will read full hot if you ground the sender directly.

Regarding power, a 1600 is not going to have the grunt of your 302 Ford! It should pull smoothly to 6000rpm and feel like it's building power until it approaches redline. It would be a good idea to drive a similar car so you can judge what to expect power wise and to determine if you're down. Ignition timing is extremely important for the engine to make power. A non-smog stock or EI dizzy curve should be good. I think peak torque in a 1600 was at 4200 rpm.

bossbob wrote: Mon Dec 05, 2022 2:08 pm It is a smog delete with a smog distributor, can that be part of the problem.

You need to use the non smog distributor like the one on the left. 7.5 = 15 degrees as opposed to the smog one on the right. 17.5 = 35 degrees advance. It is severly retarded, = runs hot and dog performance.

So it all comes down to the distributor? I did buy a 7.5 plate. Can I just swap it out or are the springs different?

Greg, I did replace the VR with a solid state unit and I think the sender is properly grounded, I actually went back and removed it to take off the teflon tape I used when I originally installed it.

Thanks for all the input.

Springs are different.

david premo wrote: Mon Dec 05, 2022 5:20 pm Springs are different.

Weights are the same, but the springs are different. Premo and Stan told me so.

The two part design on these distributors offers some issues and solutions. The lower half is gear driven and feed by an oil supply under pressure from the motor. The bushing that the distributor shaft is living in will still wear out over time. If you still have a dwell meter and use its after you have sent the point gap and your meter is bouncing at the reading, the shaft is gimbaling in the housing. Your car will run, but never quite rite.

One more reason why I had mind rebuilt.

I do have my old dwell meter still, and can check next time I'm on the car.

Where can I buy the springs for the distributor?

Since this is a 1600, it could be that the temp sender is picking up the heat from the exhaust port and header depending on where its installed. On the 1600 I race we had an issue with the temp gauge reading 240 degrees all the time. We checked everything and came to the conclusion that it was a false reading due to being too close to the exhaust port. Since the car has a custom radiator with a fill port on it (similar to a U20 radiator) I was able to remove the tower and run a U20 thermostat housing and outlet that also allowed me to move the temp gauge sensor there. No more false readings. WIthout having a U20 radiator you can't do this on an R16, and it only works if you have a two bolt tower that allows you to use the U20 outlet. It took a little modification to the U20 outlet, but nothing more than ovalizing the mounting holes a little bit.

Will

Where can I find the springs for the 7.5* plate? Or do I have to pony up the $$$ for a new distributor? Thanks again.

bossbob wrote: Tue Dec 13, 2022 11:47 am Where can I find the springs for the 7.5* plate? Or do I have to pony up the $$$ for a new distributor? Thanks again.

Maybe PM Tom (notoptoy) or Mike Young and see if they have any laying around.

On a separate note, if your temp gauge is reading 250(ish) but you’re only seeing 170 at the thermostat housing, your gauge is not properly calibrated - Don’t rely on it for diagnostics.

bossbob wrote: Tue Dec 13, 2022 11:47 am Where can I find the springs for the 7.5* plate? Or do I have to pony up the $$$ for a new distributor? Thanks again.

Stan Chenoff has em. I think he's "fossil" on 311s.

Is temp gauge part of the circuit that gets regulated down to 8~v? Maybe the lil regulator failed?

Back to this again.

I replaced the VR with a Solid State unit, so I think that is good.

Hasn't been warm enough here for it to really get hot again, but high revs on the freeway will get the temp up. Seems the longer I drive it the hotter it gets.

If it were your car, would you address the radiator first or the distributor? I believe the radiator is flowing well, I haven't been able to find the springs for the distributor, and just can't wrap the $$$ around my head for a new distributor, even the basic electronic ones are pricey.

Thanks again.