63 FI engine temp

[Michael G.]

Can someone tell me the recommended upper coolant temperature on a 63 L84 engine? (This is not another percolation question, I just want to understand what temperature is safe for the mechanicals)

thanks,

[Duke W.]

Re: 63 FI engine temp

With a 180 degree thermostat the normal coolant temperature range is 180-230F. The high end is possible in low speed driving in very hot weather. With a 15 psi cap and a 50/50 glycol mix, the boiling point is 265F.

Duke

[Jim W.]

Re: 63 FI engine temp

With a good sealed coolant system and a good seven blade fan and the clutch & 15 PSI radiator cap, it should run right around 200 to 220 degrees. Likewise the engine needs to tuned and timed right to specs. My 79 in stop and go traffic never ran higher than 220 with the A/C on and a outside temperature around 85 degrees.

[Duke W.]

Re: 63 FI engine temp

Your '79 is an emission controlled engine. The OE thermostat is 195F and the fan clutch doesn't tighten until a higher radiator exit temperature than pre-emission engines.

Pre-emission controlled engines should run, most of the time, at or near the thermostat opening temperature if the cooling system components are performing properly. Expect higher coolant outlet temperatures in low speed/hot weather traffic if the ambient temperature is over 80.

The reason why most modern cars have idiot lights is that it stops all the customer complaints about "overheating". They think "boiling" is 212F because they don't understand that a proper coolant mix and pressurized cooling system doesn't boil for at least another 50 degrees.

On modern Corvettes, I don't think the fans engage until 230F.

Duke

[George J.]

Re: 63 FI engine temp

Michael,
my '65 fi car runs about 185 to 195. I am sure if I let it idle or crawl along in traffic for a while it would get hotter. The guage goes up faster than the actual temperature as has been talked about before.

Now, since it is a coupe, and Glen Green on black car, the interior gets up to about 250, or so it seems.

George
31887

[Guest]

Re: 63 FI engine temp

Michael,

Was great seeing youse at National - on my round trip from Balmer to Novi and back home, Lady's temp hovered around 170 on the open hiway - she definitely did not like stop and go traffic as temp creeped over 200 and the fuel injection unit was percolating - definitely did NOT like to restart after pit stops

[Duke W.]

Re: 63 FI engine temp

The '63 FI engine has ported vacuum advance, which will make it run hotter in low speed traffic/hot weather than other non-AC '63-'67 327 engine configurations, all of which have full time vacuum advance.

Duke

[Michael G.]

Re: 63 FI engine temp

Good to see you at Novi too, Rick.

On the way from Novi to my house in Pinckney (maybe 17 miles) the blue car (I gotta get a name like "Lady" for it) got up to about 230 F at the interminable traffic light at Beck Rd, but normally varied between that 210 and 180 in cruising. It was hot outside on Friday, so I didn't think that was bad. I was running 110 racing gas (with no alcohol) so percolation was not an issue.

I drive my black car a lot and it normally runs cooler that that, but the sending unit is a repro, so all bets are off.

Thanks,