Engine Running Hot

[Bubba]

I have a 74 1.8 carbed, it normally runs just above the half way point on the temp gauge. But today the temps got into the mid 80s & my engine temp gauge jumped almost into the red & my idle also jumped up to about 2 gran. Any advise or tips on this?

[JP Noonan]

Running lean can increase your idle and will make the motor run much hotter.

Check the carb, maybe varnish is blocking a jet? Or maybe it's a massive vaccuum leak.

In any case fix it asap or you will likely crack a head, suck a vavle, or puke a lung (blow a piston). Running hot is VERY bad for aircooled motors. BTW did it get so hot that it started missfiring? Over heated motors start pre-detonanting from the heat just before the grenade.

Except for the fact your idle jumped up it may also be a mismatched gauge/sender combo. Is this the first 80 degree day you've had the car?

[rich]

Check the cable and thermostat that operate the flaps on the fan housing. Also the bolt that holds the pulley the cable runs around. Good luck

[Dave at Pelican Parts]

Also check the timing. Over-advanced timing will make the idle much higher, and will also make the engine run hotter.

Besides, the first thing to check when you suspect an induction system problem is the ignition.

--DD