88 toyo 4x4 installed new radiator and all hoses now not running very well was fine before

Fill radiator, do not install radiator cap. start car and continue to fill the radiator until full. Install cap.

Check hose going to M.A.P. sensor not broken both ends or cracked.

Sounds like your water pump may be not working, while vehicle is off try squeezing both upper and lower radiator hose you should be able to feel the fluid in the lines and the hose should feel firm and not squish all the way together. Make sure you used the right coolant orange vs green and mix ratio. after all this has been confirmed start vehicle and squeeze hoses again before they get to hot to make sure the fluid is moving and now hoses should be pretty hard to squeeze at all while the truck is running. if you don't feel movement of fluids or hoses are very squishy it could be a vacuum leak and worst case your water pump, hope this helps-

vehicle cold, remove radiator cap. see if coolant pushes out of radiator. if so, blown head gasket. if not recheck thermostat and or installation. make sure to bleed air from cooling system. while running burp upper radiator hose with hand. upper hose will get hot once system is operating properly.

Is it possible the replacement engine has a water pump that turns the opposite direction from the original ?
The thermostat has to be open to allow flow thru the radiator, have you tried running without a thermostat to check flow ?

leave well alone it runs and doesnt overheat ,thermostats come with different temperature ranges ,82?c to 98?c average is 88?c or 92?c ,dont interfere with it leave it alone its fine

A.T., 4x4, AOD (5.0L)
EAC}G}}400" type="radio" name="userInterchange" />A.T., 4x2, AOD (5.0L), 11-1/4" ext hsg
EA}}}400" type="radio" name="userInterchange" />M.T., 4 spd (Warner T-18), 4x4
M.T., 5 spd, Mazda/Toyo Kogyo, 4x4
M.T., 5 spd, ZF, 4x4, 8-460 (7.5L)
M.T., 5 spd, ZF, 4x4, 8-445 (7.3L, diesel)
EAA}N}}400" type="radio" name="userInterchange" />A.T., 4x2, AOD (5.0L), 10-1/4" ext hsg
M.T., 4 spd (Warner T-18), 4x2, 12" ext, cable drive speedo
M.T., 4 spd (Warner T-18), 4x2, 12" ext, elec speedo
M.T., 4 spd (Warner T-18), 4x2, 4" ext, cable drive speedo
M.T., 4 spd (Warner T-18), 4x2, 4" ext, elec speedo
F>}A}}400" type="radio" name="userInterchange" />A.T., 4x4, C6, 8-460 (7.5L), (elec speedo), (tag F2TP-YA)
M.T., 5 spd, ZF, 4x2, 6-300 (4.9L), cable drive speedo
M.T., 5 spd, ZF, 4x2, 8-351 (5.8L), cable drive speedo
M.T., 5 spd, ZF, 4x2, 6-300 (4.9L), elec speedo
M.T., 5 spd, ZF, 4x2, 8-351 (5.8L), elec speedo
M.T., 5 spd, ZF, 4x2, 8-460 (7.5L), cable drive speedo
M.T., 5 spd, ZF, 4x2, 8-460 (7.5L), elec speedo
M.T., 5 spd, ZF, 4x2, 8-445 (7.3L, diesel), cable drive speedo
M.T., 5 spd, ZF, 4x2, 8-445 (7.3L, diesel), elec speedo
M.T., 5 spd, ZF, 4x4, 6-300 (4.9L), ID E9TA-TA & TB
M.T., 5 spd, ZF, 4x4, 8-351 (5.8L), ID E9TA-TA & TB
M.T., 5 spd, ZF, 4x4, 6-300 (4.9L), ID F4TA-BA & BB
M.T., 5 spd, ZF, 4x4, 8-351 (5.8L), ID F4TA-BA & BB
>C}}}400" type="radio" name="userInterchange" />M.T., 5 spd, Mazda/Toyo Kogyo, 4x2, elec speedo
>D}A}}400" type="radio" name="userInterchange" />M.T., 5 spd, Mazda/Toyo Kogyo, 4x2, cable drive speedo, 2.73 ratio
>D}A}}400" type="radio" name="userInterchange" />M.T., 5 spd, Mazda/Toyo Kogyo, 4x2, cable drive speedo, 3.08 ratio
>D}B}}400" type="radio" name="userInterchange" />M.T., 5 spd, Mazda/Toyo Kogyo, 4x2, cable drive speedo, 3.55 ratio
>D}B}}400" type="radio" name="userInterchange" />M.T., 5 spd, Mazda/Toyo Kogyo, 4x2, cable drive speedo, 4.10 ratio
A>}}}400" type="radio" name="userInterchange" />A.T., 4x2, E4OD, 6-300 (4.9L), (elec speedo), ID F2TP-BA
A>}}}400" type="radio" name="userInterchange" />A.T., 4x2, E4OD, 6-300 (4.9L), (elec speedo), ID F2UP-DA & DC
A>}}}400" type="radio" name="userInterchange" />A.T., 4x2, E4OD, 8-302 (5.0L), (elec speedo), (ID F2TP-DA)
A>}}}400" type="radio" name="userInterchange" />A.T., 4x2, E4OD, 8-351 (5.8L), (elec speedo), ID F2TP-FA
A>}}}400" type="radio" name="userInterchange" />A.T., 4x2, E4OD, 8-351 (5.8L), (elec speedo), ID F2UP-EA, EB & EC
?}}}400" type="radio" name="userInterchange" />A.T., 4x4, E4OD, 8-351 (5.8L), (elec speedo), (ID F2TP-HA)
}}}400" type="radio" name="userInterchange" />A.T., 4x2, C6, 8-460 (7.5L), (elec speedo), ID F2FP-CA & DA
A.T., 4x4, E4OD, 8-460 (7.5L)
E}}}400" type="radio" name="userInterchange" />A.T., 4x2, E4OD, 8-445 (7.3L, diesel)
A.T., 4x2, C6, 6-300 (4.9L), w/o ID F2FP-BA; w/o ID F2UP-CA
A.T., 4x2, C6, 8-351 (5.8L), w/o ID F2UP-CA
A.T., 4x2, C6, 6-300 (4.9L), w/o ID F2FP-BA; ID F2UP-CA
A.T., 4x2, C6, 8-351 (5.8L), ID F2UP-CA
A.T., 4x2, C6, 6-300 (4.9L), ID F2FP-BA
A.T., 4x4, E4OD, 8-445 (7.3L, diesel)
A.T., 4x2, E4OD, 8-460 (7.5L)
A.T., 4x2, C6, 8-445 (7.3L diesel)
EF}D}}400" type="radio" name="userInterchange" />A.T., 4x4, C6, 8-351 (5.8L)
Good luck

Just follow the big hose on top af the radiator down to where it goes into the motor,The piece it connects to is the thermostat housing,Just remove the bolts and pull it off,You will see the thermostat,Replace with new one in the same direction as the old one is setting,and bolt back together.



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Check to make sure the air is bled out of the system by removing the cap on the bottle and the heater hose at the thermostat housing. When fluid starts running out of the housing, reattach the hose and test again.