Engine over heats when towing camper
 

Hey fellas
First time poster to this forum. I have a 86 and when I pull my camper the engine has a hard time. The engine is a 350 and everything looks stock. The camper is 30 foot long and weighs less than 5,000 pounds. The people I've talked to have said that the engine is plenty big enough. When I travel down the highway I have a hard time keeping the speed above 60 mph. But if I stay at 60 the temp gets pretty hot. If there's a small hill there's no way I can keep the speed above 50. I need some help!! Is the radiator too small?
Thanks
Chuck

Welcome Chuck,

It could be a number of things, Do you have over sized tires? Larger than original equipment sized tires will change the final ratio, which will put a larger load on the engine and drive-train. Is your fan clutch working properly? Have you serviced the cooling system since this over heating started (flush, antifreeze, thermostat, check to see that the antifreeze is being pumped through the system) I’ve seen water pump impellers loosen up on the pump shaft and will not pump antifreeze “free-wheeling” even though the pulley is spinning, check for positive flow, this can get tricky, as you need enough heat to keep the stat open and that heat could scald you of course. Your radiator could possibly have partial blockage. Is your radiator cap holding the correct pressure?

Take a look at your antifreeze strength
Not only is it antifreeze , it also increases the boiling point

That is a lot of trailer for that old girl
You need to be aware when towing something like that in the hills
Sometimes you need to take a run at the hills but pretty common to loose speed at the top

Lean fuel mixture will also produce extra heat and lack of power, i had an 86 cutlass that the carb had been rebuilt on and they forgot the little cam piece that lifts the secondary metering rods to send fuel when those top secondary butterflys open, anytime you were in it enough to open the secondarys it was leaning out bad, melted a piston before i figured it out, it squealed and rattled like crazy, looked like a 2 stroke that someone had forgotten to mix oil in the gas, aluminum smeared all over the cylinder walls. Im sure yours isnt that bad but changing the fuel filter and doing a pressure test at wide open throttle shouldnt be overlooked. Also check timing and other basic stuff and dont chase only the cooling system, do check for good flow though and that the fan clutch is working for sure.

yeah could be crappy gearing. if you got a 350, 35 inch tires and 273 gears be happy that thing can move itself. also check the front of your radiator make sure its not full of mud and weeds or whatever else.

also if you have a lack of power the cat might be clogged also