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Idiot Questions - New Owner

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So, I have been tooling around town in the 68' Datsun i recently got and i have a few noob questions about it running. I figured id put them all together to avoid tons of 1 reply posts. So without further ado...


Q1: I dont have a temp gun so I have to rely on the dash gauge. What is considered "running hot" vs optimal temp? When going around town, the guage reads at between the second line and middle point (covering the thermometer logo). On the highway, this gauge reads at the half way point. Is this considered good? From what i know, it is running the stock radiator which has an electric fan attached rather than the old engine driven one. 


Q2: on a related point, when the temp gauge reads at above the second line but below half way, the car is prone to mis fires (a few revs fix this sometimes) and when warm (half way mark) it seems to have problems idling and on occasion has died. Im taking it to the shop to see if a carb tune can solve this and push off a carb rebuild for a bit or if its futile. I do know one carb runs rich and the other runs lean which probably doesnt help things. 


Q3: most of the people I talk to seem to let their car idle for several minutes when starting cold until the needle hits the second mark on the temp gauge. Recently, i have been running for about 30 seconds with choke and 30 seconds without choke and once the engine idles normally, i take off. This is my first carburated car so... what do most of you do? 


That's mostly it for now. The car is in a pretty rough shape for its overall condition when i got it, so i dont entirely know what is "normal" for the car and dont want to do any additional damage that could be solved by some knowledge. Any insight to this would be awesome!

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The Datsun gauges usually has a marked 'run range' I assume the Roadster is similar. My Datsuns run about 1/3 of the way up into the run range around town and just under half way on the highway. There are no numbers because most drivers will freak out as the needle goes up whereas just going up 1/4 the gauge means nothing. Your Roadster gauge is more for alerting you to any reading that is above what you are used to seeing. In other words if it has normally run at half way and suddenly starts reading 3/4 then something may be wrong.



This may be related to your carbs being out of sync. One is doing the work of the other.



 Gas engines are instantly ready to be driven and do not require long warm ups. On cold days start engine and check your mirrors, put seat belt on, check gauges, put lights on and you can go. 30 seconds is plenty. Naturally drive lightly till the temp gauge settles down to normal temperature. If the weather is such that the windows need to be scraped the warm up takes care of itself. Otherwise, excessive idling just fouls the plugs and wastes gas you could be driving on. The car will warm up much faster if you are driving it.

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Get a hold of an  infrared thermometer and check it against that. It will give you a base line to work off of.  As far as the carbs and warm up goes, I drive my 2000 with a bit of choke< 1/2" pulled out until the temp gauge comes up off of the bottom and past the first mark.  Unless it is above 85 air temp which has been pretty much all summer here.

Also go sign up on 311s.org and all your Roadster questions will be answered.

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