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351w swap overheating problem,please help

  • Thread starter Thread starter my84gt912
  • Start date Start date Nov 29, 2011
M

my84gt912

New Member
Jul 22, 2011
8
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0
Nov 29, 2011
#1
  • Nov 29, 2011
  • #1
ok I just bought a 97 that has a 89 351w from a ltd.it was over heating.it had the bottom bypass blocked and the top bypass to the heater core and the other heater core hose to the thermostat nipple.nothing to the intake.so i bought a nipple to fit the intake and now I have the top bypass hose to the thermostat nipple,the lower bypass the the heater core and the other heater core to the intake nipple.still no change with over heating.took the water pump off and i noticed the timing cover was for a standard rotation water pump(clockwise) so I bought a reverse flow timing cover and installed the counter clockwise pump and a 160 stat.still over heats.there is no oil mixing with antifreeze or vise versa.I took the stat out and it ran almost 220.I have a fluid dyne radiator and a electric fan on it.i also took the hose off the thermostat housing and had a garden hose in the top radiator hose and started the car and there wasnt constant flow coming from the stat houseing.is this normal and what can the problem be
 

Three50won

10 Year Member
Jul 11, 2010
1,135
64
69
Nov 30, 2011
#2
  • Nov 30, 2011
  • #2
my84gt912...what were the actual temps when the thermostat was in? Maybe the gauge is broken. Did you try an infrared temp gun to double check? Maybe there is a blockage somewhere in the system. BTW, are you sure it's a 351W? Are we talking about a Mustang? Are you sure they did a full pushrod conversion? Do you have any pics? Not to insult you or sound rude but I'm sure you know the difference between a 351W and a 4.6 SOHC NPI engine...
 
M

my84gt912

New Member
Jul 22, 2011
8
0
0
Nov 30, 2011
#3
  • Nov 30, 2011
  • #3
It was running 235-250.according to the block casting numbers its a 89 351w out of a car not truck.
 

Three50won

10 Year Member
Jul 11, 2010
1,135
64
69
Nov 30, 2011
#4
  • Nov 30, 2011
  • #4
my84gt912...did you burp the system properly? I'd say unblock everything, hook everything back up, then disconnect the lower hose and manually spin the water pump in one direction...see what happens. If nothing then spin it the other way and see what happens. If nothing then try to flush it. If flushing it doesn't work then maybe check to see if your thermostat is opening properly. While you're at it check to make sure the fan is operating properly. Maybe try to flush the radiator to figure out if the blockage is in the rad or the block. I have no other advice outside of that...sometimes you have to step back, take a deep breath, and start all over from the beginning just to rule things out because it might be something simple that you overlooked. Good luck my friend.
 
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