525sc - what thermostat and engine temps
#21
Registered
Join Date: Jun 2002
Location: WEST MONROE,LA.
Posts: 259
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
OK, OK . Still havivg a issue with the port motor water temp going up to 170-175. However, I ran the motor on the hose and the temp would cycle down to 120-130 after running the rpms up to 1500 and then would rise back to 175. Please advise on how I can keep the temp right around 150. Thanks again Scott
#22
Charter Member # 55
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
I was out of town and just saw this.
I would not pay attention to temps running on the hose. Mine would always cycle up and down like you described.
I would verify the temp readings you are seeing by swapping guages. Actually you only need to swap the sender wires on the backs of the guages.
It could be a guage, sender or combo of both of them being out of calibration.
I would not pay attention to temps running on the hose. Mine would always cycle up and down like you described.
I would verify the temp readings you are seeing by swapping guages. Actually you only need to swap the sender wires on the backs of the guages.
It could be a guage, sender or combo of both of them being out of calibration.
#23
Registered
Join Date: Jun 2002
Location: WEST MONROE,LA.
Posts: 259
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
Griff, need some help here!!!!!!!!!! We have checked sending units, guage, thermsotats, sea water pumps and back flushed the motor. But the motor is still running around 165-170 at 3500 rpm and about the same at idle. One other thing I have noticed is that my water pressure guage is showing 10-12 and at times it will cycle down to about 2-3 and then cycle back to 10. ???????????? Any input would be GREAT. thanks again Scott. ( Other motor runs around 150 on the guage.)
#25
Charter Member # 55
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
The water pressure changing is strange. I have not seen h20 pressure change when rpms and speed remain constant.
I have to wonder if you might be sucking in some air. Do you have a DWP drive???? I have heard of them sucking air through the top holes.
Another thing might be a hose collapsing from the suction of the sea pump.
I'm kind of guessing at possibilities. You could also try to try and put a "band aid" on it by trying some stuff. You could try a 120* Tstat and see if the temp drops. You could also try and drill (3) 1/8" holes in the current Tstat and see if that helps.
You really do need to find the root cause of the higher temps though. Its not real severe, so it might be tough to track down. With the higher temps and changes in water pressure, I'm guessing there is an obstruction somewhere or you are sucking in some air somewhere.
I have to wonder if you might be sucking in some air. Do you have a DWP drive???? I have heard of them sucking air through the top holes.
Another thing might be a hose collapsing from the suction of the sea pump.
I'm kind of guessing at possibilities. You could also try to try and put a "band aid" on it by trying some stuff. You could try a 120* Tstat and see if the temp drops. You could also try and drill (3) 1/8" holes in the current Tstat and see if that helps.
You really do need to find the root cause of the higher temps though. Its not real severe, so it might be tough to track down. With the higher temps and changes in water pressure, I'm guessing there is an obstruction somewhere or you are sucking in some air somewhere.
#29
Charter Member # 55
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
I would try plugging the top hole or 2 on the sides of the drive. Use brass pipe plugs.
EDIT
Disregard plugging the sides, since the temp is high at idle as well.
EDIT
Disregard plugging the sides, since the temp is high at idle as well.
Last edited by Griff; 08-11-2008 at 11:49 PM.
#30
Registered
Join Date: Jul 2007
Posts: 13
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
on injected motors with a typical recirc water pump, with a standard tstat ( no holes or other voodoo) the water temps should be above 160 or you are telling the injection to be over rich... not smart.
not smart on carb motors either but not essential like it is with injection. a good injected , normally aspirated motor will run for 200 years at 170 deg... where it should be anyway.
not smart on carb motors either but not essential like it is with injection. a good injected , normally aspirated motor will run for 200 years at 170 deg... where it should be anyway.
Hi Steve, could my problem with uneven idle be do to to cold operating range 140F on my 350 mag mpi? Cannot find out what is wrong.. Are