what water temps on a 500 efi should be
 

bought boat 2001 one motor runs 165 and takes a wile to warm up when cold, the other when crant up goes to 130 real quick then run around 185 not even running hard even at 3000rpm water presure on this motor o psi at idle and around 3000 rpm it 15 20 psi ,what have yall seen?
rob

Rob,

We just fixed ours. 2001 500efi, its your thermastat. I bet you have right at 50 hrs on your motor. When it was new it ran 148-152 all the time. Then after a year of use it would slowly go up to 180 and then drop quickly to 140. Put in new thermstat and it stays at 151 now wich is a good temp for the 500efi. When you buy the thermstat make sure you get a new seal also. Inexpensive part like $20 , and one that could really mess up a nice motor.;)

As for water press I see have the same.

WILL

i hooked a merc scan tool last nite the gaffrig gage is off 10 degrees, was still reading 168 at idle in slip gage was 173-175 still seem high the merc manuel says 160 therm but the owner manuel says 143,going to change the impellers and therm just for the hell of it??new boat blues