540 heating up with stat installed
06-10-2009 | 07:04 AM
#11
Thread Starter
Registered
Joined: Feb 2008
Posts: 6,759
Likes: 158
From: Connecticut
I am having the same issue. I have a 142 stat with 3 3/16 holes in it. Crossover with bypass. Mine goes to 200. Prior motor with same set up went to 190 on Gaffrig guage, but on the prior Faria guage it was 160. I still have the Faria guage and I am going to see what it says.
06-10-2009 | 07:49 AM
#13
Thread Starter
Registered
Joined: Feb 2008
Posts: 6,759
Likes: 158
From: Connecticut
i may have not made my self clear. w/ a crossover motor i don't think you want an operating tstat at all. i am suggesting a flat plate with a 1" hole in it in PLACE of the stat. an easy way to accomplish that is to knock th center operating mechanism completely out of a stat... thats just an easy way to accomplish the same thing. it is NEVER a good idea to drill holes in a stat in an attempt to change its calibration or act as a by pass.
06-10-2009 | 08:07 AM
#15
Registered
Joined: Oct 2005
Posts: 1,899
Likes: 20
From: Millstadt, IL
i may have not made my self clear. w/ a crossover motor i don't think you want an operating tstat at all. i am suggesting a flat plate with a 1" hole in it in PLACE of the stat. an easy way to accomplish that is to knock th center operating mechanism completely out of a stat... thats just an easy way to accomplish the same thing. it is NEVER a good idea to drill holes in a stat in an attempt to change its calibration or act as a by pass.
06-10-2009 | 08:34 AM
#17
Registered
Joined: Jul 2002
Posts: 2,867
Likes: 3
From: Waterford,MI
The EFI motors are supposed to have 160 deg. thermostats. The computer will think the motor is still cold with anything less and tend to run rich. A cross over with a bypass is meant to run with a thermostat Mine runs rock solid at 120 degrees with a 120 degree therm. and 2 1/8 holes drilled in it. My bypass uses a 3/4' hose, how large is yours? Oil temp lower than water temp doesn't make a lot of sense. I would double check the gauge. If it checks, then the problem is likely related to water flow. Check all of the usual things, impellor, hoses, make sure nothing is plugged etc.
06-10-2009 | 08:51 AM
#18
Registered
Joined: Feb 2005
Posts: 570
Likes: 47
From: cincinnati,oh.
Oil temp. does seem low. I have a 540 also with a 140 t-stat. I do run a circulation pump on the motor. Temps. always stay at 140 on the water. I also use a t-stat on my oil cooler .The oil runs from 215-235. What type of water pickup do you have?
06-10-2009 | 09:00 AM
#19
Thread Starter
Registered
Joined: Feb 2008
Posts: 6,759
Likes: 158
From: Connecticut
The EFI motors are supposed to have 160 deg. thermostats. The computer will think the motor is still cold with anything less and tend to run rich. A cross over with a bypass is meant to run with a thermostat Mine runs rock solid at 120 degrees with a 120 degree therm. and 2 1/8 holes drilled in it. My bypass uses a 3/4' hose, how large is yours? Oil temp lower than water temp doesn't make a lot of sense. I would double check the gauge. If it checks, then the problem is likely related to water flow. Check all of the usual things, impellor, hoses, make sure nothing is plugged etc.
06-10-2009 | 09:01 AM
#20
Thread Starter
Registered
Joined: Feb 2008
Posts: 6,759
Likes: 158
From: Connecticut
The EFI motors are supposed to have 160 deg. thermostats. The computer will think the motor is still cold with anything less and tend to run rich. A cross over with a bypass is meant to run with a thermostat Mine runs rock solid at 120 degrees with a 120 degree therm. and 2 1/8 holes drilled in it. My bypass uses a 3/4' hose, how large is yours? Oil temp lower than water temp doesn't make a lot of sense. I would double check the gauge. If it checks, then the problem is likely related to water flow. Check all of the usual things, impellor, hoses, make sure nothing is plugged etc.
