Originally Posted by betty55
My son's 55 chevy truck with a 350 engine was running great. He took it to dyno it and all hell broke loose. My son is the quiet type but after the experience I feel like he is a volcano waiting to explode. He was not at all impressed by the operator of the dyno. My son tried to explain a few things about his shifter, etc.. this guy was capped and didn't hear anything he said.
He did 4 runs in overdrive and did not pay attention to the gauges at all. He got the truck so hot it damaged several parts. All the water in radiator exploded out, it went everywhere. After long cooling period, he left the shop drove to stoplight, tried to U turn but couldn't get into first or second gear. He then said it got HOT FAST and he waited for a good hour for cool down. Then he noticed that it was shifting at higher RPMS than before dyno disaster. We worked the shifting probem out but this engine NEVER ran hot before dyno and has run very hot since. It seems its ok on freeway, but he
gets off the exit up to a stop light at idle and that sucker climbs up fast to 210 +.
We just spent $2500.00 to diagnose overheating issue. We've bought new starter, new water pump, new bigger fan, thermostats, etc..... did not fix it. had our machinist go through and make it brand new again. Rebuilt it last week and it still overheats. On rebuild we notice the aluminum radiator fins were all bent and appear to have swelled outer casing,the core tubes and fins are all blocked off closed. You can't see through at all.
COULD DYNO PRESSURE AND HEAT HAVE WARPED AND DAMAGED THIS RADIATOR TO THIS DEGREE?
AGAIN WE ARE SURE THIS IS THE CAUSE AND FIX, SO OF COURSE WE'VE ORDERED A NEW RADIATOR $$$$
WE THOUGHT EACH PART WE REPLACED WAS THE CAUSE AND FIX. IT WASNT.
ANY INPUT IS GREATLY APPRECIATED.
The dyno operator doesn't know what he's doing, you never run a chassis dyno with the machine to be tested in a high gear, the first and foremost event is the drive shaft coming out, which is why this is done in lower gears.
Running it the way this guy did sure could take out the radiator if it got so hot the coolant just exploded out of the system.