Datsun Roadster Forum-311s.org

After taking a few spins around the block (3 or 4) the roadsters temp seems to start rising. It runs at about 190 at the first two spins and then it slowly rises, I parked it rather than to experience it overheat!! What could cause it to run kinda hot? And what temps are fine for it to be running at?

Joaquin

Hi Joaquin,

Make sure you've got it timed for the dist. you're using. Make sure it's not too lean. Check water. If it starts to overheat really quick, go through and check everything. It should take a while to warm up so if it gets hot right away chances are something is way off. What kind of temp guage? Stock? Make sure the temp is actually where the guage says it's at. Normal temp 180-190. I have an aftermarket guage and on cool days it will run around 160 if I'm not pushing it, 180 when I drive it hard. On hot days I'll see it at 185 most of the time. Be sure you're running the thermostat too. I left mine out and it ran too cold and performance suffered. WHen I first had mine, the head had been redone and it was running hot because the head wasn't torqued properly.
Ron

Ron,

The distributor is on right timing, it did however need a bit of water, 1/4 of a gallon, and yes, I am running on stock gauge. I think I might have to retorque my head. It doesnt get hot right away, if its sitting, it will take it about 20 min to get it to 180-190 degrees. I also have another thermostat that I might install (i dont trust stock guages). Thanks for the heads up Ron, I will try check everything again, just to make sure its all set up right .

Thanks, Joaquin

It sounds like it's warming up ok. 20 minutes is good. If it gets there and keeps going could be the thermostat not opening. There are 2 different kinds also. 180 and 195? Make sure you've got it installed correctly. Spring down? Test it in boiling water and make sure it opens. Also make sure that your radiator oroverflow caps aren't too strong. 7lbs, not 13.
60lbs on the head, follow the bolt pattern in the shop manual. Do you have a manual?
Ron

Joaquin,

A good way to test if for sure is to get a Temp laser. You can point it at any part you want and read its surface temp. This may save you some hassle. They sell them at Napa, ebay, etc..

Alexi

Ron, how do I take the thermostat out? Yes, I do have a shop manual.

Alexi, I think I my I know where there might be one lying around(uncles shop).

Joaquin

i don't think tha laser gun will work. the temp you see is the water temp. the block is acutally hotter. You have nothing to judge from. what does the head see when the gauge says 180?

i hoping to drive mine around the block today..just charging up the ol' battery

steve

Steve,

The laser gauge does not read water temp it reads surface temp. So you can take readings at various points around your engine bay. It is handy if you are racing and you want to read your tire temp and different points to find the right amount of psi for the track, or as in Joaquins case he can find if his gauge is truley acurate or not.

Alexi

i understand how it works..but thats the problem it takes surface temp. the guage in the car is water...how can make sure its accurate when its taking a temp reading from something different? water temp and the acutally engine block temp is totally different.
he would be better off getting a aftermarket temp guage..pretty cheap from autozone or discount. less than $20 i believe

steve