i have a 1978 toyota 4x4 pick up with a 20r. i have an overheating problem and i have lost power, i have changed the themostat the coolant got new hoses flushed the radiator any info? i also have a power problem driving down the road it just cut out on me i had the gas all the way down and never got over 30mph any info would help thx!!!!

 

do you have to keep adding coolant or water to the system?
is your engine puffing white smoke/vapor?
gray-ish colored oil?

any of those symptoms could mean blown head gasket or cracked/warped head.

my 82 has a blown gasket,has all those symptoms mentioned,and lost power.

have you ran a compression test onthe cylinders?

 

no i dont need to add coolant level stays the same.
no smoke
and the oil is clean!

the truck sat a few months before that is was fine when i got it started again the overheating started.

 

hmmm.im wondering if the exhaust system may be plugged up,if its obstructed iknow you wont have power.
but not sure if that would cause her to overheat.

try disconnecting the heater core and running it again,may have a blockage.
does the engine seam more powerful when cold,then loses power once she starts to overheat....or sluggish from the start,stays sluggish once warmed up?

 

well i think i may have found the power problem the gas inlet on the carb is gummed up! but i still cant find the overheating problem i just put a new electric fan on to.