Look at this picture..Is this too high

[sblake01]

Use a relay. I have relay on the auxiliary electric fans on both my Z and my 810. Though both cars have the later type alternator, I notice no drop in voltage when the fans are on.

[Caen Fred]

What about driving without thermostat?????????????

[sblake01]

Driving without a thermostat could cause the operating temperature to be too low. I don't know how important that is on the carbureated cars, though I'm sure it is, but on the fuel injected cars it can throw the fuel mixture off.

[mally002]

If anyone has any info on driving w/o a thermo with a 240 I would like to hear it. I was thinking I might pull mine off just to see if it still overheated. Would that be a worth while test to conduct???? Any harm??

[deadflo]

I just bought a 170 degree Nissan OEM 'stat off ebay to install in the 240. I think it will keep her a bit cooler during the summer, I dont drive her much in the colder part of the eyar.

[mally002]

So you were the one who out bid me.....:eek:

[byunique]

HOT HOT HOT. The only time my car has registered that high is when it was having cooling issues. Especially the 3rd picture.

BTW, one time I had a 160deg thermostat, don't think it was Nissan but it was still too hot for a summer day down in Los Angeles. Swapping do a different 160 deg thermostat with larger diameter solved all of my cooling issues! Couldn't believe the night/day difference. Both were aftermarket new items too.

[kcoke]

I run my 240z without a thermostat and it stays at a good temperature. A thermostat is only useful for cold days and I dont drive my Z on a cold day.

[Mckrack]

Last picture on right too high. Other then changing the thermostat got a stupid question for you. Is your antifreeze diluted 50/50 if not that will do it if the antifreeze is to concentrated.

[Inf]

The problem with my car is that the carbs are old and worn out so the mixture varies quite a lot depending on temperature. Generally my plugs get a little carbon buildup during startup and idling when the temperature drops a little below nominal. I had a thermostat housing with the core removed in there for a while, and if I got stuck in traffic the spark plugs would never get hot enough again to reach their 'self-cleaning' temp. I got a nissan OEM 180 thermostat, and that fixed things up. You may also want to make sure your sensor is actually reading correctly; a while back my gauge had been reading high all the time and a replacement put things back into the nominal range.

[deadflo]

So you were the one who out bid me.....:eek:

Ooops sorry. But here is another one, note its 180 degrees, BUT it is OEM and will have the larger diameter opening, I'll bet it will solve your problem.

http://cgi.ebay.com/ebaymotors/Datsun-240Z-280Z-510-Thermostat-Kit-Nissan-NOS-NEW_W0QQitemZ260121690860QQihZ016QQcategoryZ34201QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[bandoni]

i am having the same problem with my z i changed the fan clutch and it did not help so it looks like i am going to have to check on the thermostat. temp runs the same but outside temp is about 110 Fahrenheit. it only heats up past middle when i am gunning the engine and tends to stay there after i bring it back down.