Does a 73 L48 really run at 230�

[Douglas C.]

Probably an old question, my 73 runs fine, no sign of running hot. Temp gauge fluctuates from 230 to 240 while normal driving. I pointed a Snap On temp pointer at upper radiator hose after long drive and idling, thermostat open, pointer read around 150, interior gauge said around 220. Fluid level in recovery tank after long ride sits at the lower Cold mark. Owner manual says 230 is normal.

So, can it simply be GM realized the gauge / head sender was faulty and stated a "gauge" reading of 230 was normal. Tks. Doug

[Mark E.]

[Gary B.]

[Douglas C.]

Yes Gary, I thought about that. Although if say engine really running around 180 I could see upper hose maybe around 150. I have disconnected the TCS and switched to full manifold vacuum plus installed lighter advance springs. That done vs. when I first got the car with emissions hooked up and gauge read high noth ways. I just get the sense it never was really running anywhere near 230. I've been building / tuning engines for 50 years, any SBC at 230 would have obvious signs of stress IMHO. Tks. Doug

[Gary B.]

[Douglas C.]

Doug,

if you measure near the end of the radiator hose hear the thermostat I have to think you should get a reading closer to or greater than the thermostat spec if indeed the thermostat is open.

Gary

Gary, it was a quick check, around middle of the hose. I will check again in more specific spots to your points. Funny how while driving the gauge will indicate around 230, then a few seconds later it's close to 250, then seconds later down to around 220 per the gauge. Engine certainly not fluctuating that much in such short periods. I plan on changing temp sender in the head and having entire system vacuum flushed and new fluid. I know I get too crazy with things at times, but I want things as correct as possible. I just don't sense it's running at 230 +. Runs and drives smooth as silk. Tks. Doug

[Gary B.]

[Douglas C.]

I agree that it’s not actually running at 230 to 250 if it’s runny smooth as silk. Something isn’t reading accurately.

PS You should be able to see the effect if the emissivity setting if you compare the temps from the dull black radiator hose to the thermostat housing.

Gary

Gary, yes good points, will keep updating as time allows. Thanks for your comments. Doug