Yamaha F150 4 Stroke peeing cold

TheBoyScout

Thanks doesn't buy gas...
Nov 13, 2014
242
185
San Diego
Name
Ray
Boat
Bayrunner Baja 21 "Rough Rider"
When I took my outboard to the yamaha mechanic he told my my outboard was peeing cold and needed a new thermostat. So I changed it myself and sure enough the old thermostat was very corroded and had junk all over it. After I replaced it the pee stream still didnt warm up. Every outboard Ive ever had would piss warm. I could run this outboard hard and then feel the pee and its always cold or normal water temp.
Any idea what could be going wrong?
Do your yamaha 4 strokes also pee cold?
btw I have a yamaha f150xa
 

Reel Kahuna

I've posted enough I should edit this section
Mar 24, 2011
852
327
Lake Camanche, CA
Name
Seon
Boat
23.5' Navigator Duckworth F150 Yamaha
How long did you run it? It'll take several minutes to warm the motor.
 

Reel Kahuna

I've posted enough I should edit this section
Mar 24, 2011
852
327
Lake Camanche, CA
Name
Seon
Boat
23.5' Navigator Duckworth F150 Yamaha
By running it all day and the alarm didn't go off then I wouldn't be too concern. But then again, that's not my motor LOL :rolleyes:.
 

plj46

I've posted enough I should edit this section
Jan 7, 2008
7,470
7,842
Socal
Name
john
Boat
24 ft grady white
All of the outboards i've owned pee'd cold.None of them ever overheated.
 

Tesoro

I've posted enough I should edit this section
Sep 5, 2015
228
125
59
Brookings, Southern Oregon
Name
Chris Berlin
Boat
21 Arima Ranger
My engines pee colder here in southern oregon than they did in the Caribbean! 50 deg vs 84 deg!
 

Mike_I

I've posted enough I should edit this section
May 19, 2006
1,020
420
Irvine
Name
Mike_I
Boat
Cabo 216 First Love
I've got the same motor as you. The pee stream temp should be the same temp as the water source. The pee stream water is the water between the pump and the rest of the motor, the water hasn't gone thru the water jacket and picked up the heat of the motor yet, you're fine.
 

karlow

Twins 2017
Apr 29, 2004
1,726
684
63
Duarte/Covina
Name
karl
Boat
20' skippy Topless /17' whaler Wet Ride (sold) /18' Outrage
My Honda hardly pees at all! It may have stones. It has not over heated, but I don't have a good feeling about this. It pees a bit when its first started and then just dribbles even at speed. It's a new pump. The Thermostat is due on Monday. It will at lest make me fell better!

thermo.jpg
 
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plj46

I've posted enough I should edit this section
Jan 7, 2008
7,470
7,842
Socal
Name
john
Boat
24 ft grady white
My Honda hardly pees at all! It may have stones. It has not over heated, but I don't have a good feeling about this. It pees a bit when its first started and then just dribbles even at speed. It's a new pump. The Thermostat is due on Monday. It will at lest make me fell better!

View attachment 1018039
While your working on that t-stat spray some WD-40 on that motor.
 

karlow

Twins 2017
Apr 29, 2004
1,726
684
63
Duarte/Covina
Name
karl
Boat
20' skippy Topless /17' whaler Wet Ride (sold) /18' Outrage
She is a bit rough, but I have only had her about a year. The motor was in much better shape than the rest of the rig. Not so true anymore.
 

airslot

I've posted enough I should edit this section
Jun 1, 2005
276
77
45
n. ca
Name
Tom La
Boat
Mako 184
All my 4 stroke pee cold (suzuki, Honda and mercury). All my mercury 2 strokes pee warm.
 

karlow

Twins 2017
Apr 29, 2004
1,726
684
63
Duarte/Covina
Name
karl
Boat
20' skippy Topless /17' whaler Wet Ride (sold) /18' Outrage
Yep shes got rocks!
I fired her up and she was dribbling after 2 min on the hose.
I basted the pee hole with the air compressor. No help. So I pulled the hoses of the VST heat exchanger and basted it with the air compressor. She spits rocks, salt, corrosion or sand. I blast her again an repeat! She is cleaner and she will pee next time! For how long, I can't say.

pee time .jpg
 

Alexvi

I've posted enough I should edit this section
Aug 6, 2012
215
315
Santa Cruz, CA
Name
Alex
Boat
Rock Steady - Davis Rock Harbor #001
Which are you using.....the standard TM1?

The unknown fisherman:p:
TM4 - one sensor on the block, one on a riser. If you get kelp clogging the intake, the riser alarm will go off within 1 minute.
 

karlow

Twins 2017
Apr 29, 2004
1,726
684
63
Duarte/Covina
Name
karl
Boat
20' skippy Topless /17' whaler Wet Ride (sold) /18' Outrage
I have one on my Skippy Oil switch and over temp switch.
It's gone off a few times, kelp!