Hammerhead running too cool

[dino7]

Was out for several hours yesterday and noticed that the engine was running 110-120 degrees. Late in the day it felt like it was missing occasionally, and I got 2 engine faults while cruising at 35mph. My first guess is that the thermostat is stuck open, but I thought they normally stick closed. Anyone else experience this before?

thanks in advance

[REW]

Could have some sticks or junk in the seal jaming it open, but yea they usually stick shut.

REW

[mattm]

Was out for several hours yesterday and noticed that the engine was running 110-120 degrees. Late in the day it felt like it was missing occasionally, and I got 2 engine faults while cruising at 35mph. My first guess is that the thermostat is stuck open, but I thought they normally stick closed. Anyone else experience this before?

thanks in advance

What do your engine faults read?

[dino7]

What do your engine faults read?

Am I able to read those somehow? If so, please explain.

I pulled the thermostat, and it is open. There is no visible debris keeping it that way. Maybe they are designed to fail open now, that would be a better solution.

[mattm]

Am I able to read those somehow? If so, please explain.

I pulled the thermostat, and it is open. There is no visible debris keeping it that way. Maybe they are designed to fail open now, that would be a better solution.

I don't remember the exact sequence but you scroll through your main display until you get to "Service". Hit "Enter". I think the next screen will say "Diagnostic Codes". Hit "Enter" again. Write down the code and search the web, or this page. You might find your answer. You can also send the code to Indmar or you dealer to translate it.

[dino7]

I don't remember the exact sequence but you scroll through your main display until you get to "Service". Hit "Enter". I think the next screen will say "Diagnostic Codes". Hit "Enter" again. Write down the code and search the web, or this page. You might find your answer. You can also send the code to Indmar or you dealer to translate it.

Thanks, I didn;t know that.

I got 2 seperate faults.

1:

SYSTEM VOLTAGE

SPN 627 CM 0

DATA VALID BUT BELOW

NORMAL RNG

FMI 17 OC 127

2:

CRANKSIGNAL

SPN 636 CM 0

DATA ERRATIC, INT, OR

INCORRECT

FMI 2 OC 127

I think I found the problem, but won't know for sure until I get the new thermostat. In the meantime, does this mean anything to anyone?

thanks

[mattm]

Thanks, I didn;t know that.

I got 2 seperate faults.

1:

SYSTEM VOLTAGE

SPN 627 CM 0

DATA VALID BUT BELOW

NORMAL RNG

FMI 17 OC 127

2:

CRANKSIGNAL

SPN 636 CM 0

DATA ERRATIC, INT, OR

INCORRECT

FMI 2 OC 127

I think I found the problem, but won't know for sure until I get the new thermostat. In the meantime, does this mean anything to anyone?

thanks

#2 looks like it could be a crank position sensor. But, I don't know how that could affect the operating temp.