Yamaha Rhino Forum banner

1 - 19 of 19 Posts

·
Registered
Joined
·
59 Posts
Discussion Starter #1
I am having a problem with my 04 Rhino 660 temp light coming on after riding it for long periods, an hour or more, at slow speeds. If I am where I can go fast it goes off quickly. if I am where I can't, I just turn it off and let the fan run till it shuts off.

I have changed the oil and it didn't look like there is coolant in the oil.

No steam coming out of the exhaust.

Doesn't look like there is any oil in the coolant.

There is no bubbling in the radiator over flow.

From the things above I don't think I have head gasket issues. Am I wrong?

I bled the cooling system at the top point but not at the water pump. I am going to bleed it at both places and see what happens.

I don't have a winch or brush guard that could be restricting air flow to the radiator. I have washed it several times and water is clear coming out the radiator fins from washing. I am pretty sure that I am getting all of the radiator clean as I get down so the hose is getting all of it. I read not to use a nozzle since the pressure could damage the fins.

I was watching a youtube video on bleeding the cooling system and the guy said to never run the rhino with the radiator cap on. But read somewhere. on here I think, to take the radiator cap off and run it to see if the coolant was flowing though. I had already done this before watching the video and it doesn't look like there is any flow. It seems like the only fluid movement is just jiggling from vibration of the engine running.

Does the water pump run all the time? I have read that the 04 Rhino doesn't have a thermostat and I have read that only the ones sold in the north didn't have thermostats. anyone know for sure?

Any other ideas to look at?

thanks,
Trav
 

·
Registered
Joined
·
121 Posts
Yes, it's a mechanical pump that runs all the time. Two things to consider:

As you know, dirt collects between the radiator fins over time and can be hard to get out. Suggest removing the radiator to clean it so you can thoroughly flush the fins out in both directions

I've seen aftermarket shrouds on ebay etc for the 660 radiators and this may help increase your airflow considering the lower driving speeds and front hardware you mentioned.
 

·
Registered
Joined
·
59 Posts
Discussion Starter #4
Yes, it's a mechanical pump that runs all the time. Two things to consider:

As you know, dirt collects between the radiator fins over time and can be hard to get out. Suggest removing the radiator to clean it so you can thoroughly flush the fins out in both directions

I've seen aftermarket shrouds on ebay etc for the 660 radiators and this may help increase your airflow considering the lower driving speeds and front hardware you mentioned.
I'll try to see if I can remove the radiator. Not sure what you meant, In the post above I say I don't have a winch or brush guard, or do you mean something else?

thanks,
Trav
 

·
Registered
Joined
·
121 Posts
Yes, sorry I mis-read your first post where you indicated you DON'T have accessories blocking the front.

What can happen over time is we spray the radiator from the front during cleanings and dirt left in there gets pushed further in, turns to mud and dries. So it's good to make cleaning your radiator part of your maintenance program.

I also like to have a manual over-ride switch for the fan for when conditions warrant additional cooling. You can wire one up yourself for the cost of a relay and switch.

85 - ground
86 - switch on the dash with 12v power to turn on and off the relay
87 - blue wire on rad fan - use a wire tap
30 - fused 12v power from battery

Rhino-CoolingFanSwitch-708294.jpg
 

·
Registered
Joined
·
59 Posts
Discussion Starter #6
bled the cooling system at the top and bottom screw again. there didn't seem to be any air at either. I drained from the bottom screw enough fluid so that radiator was a couple of inches low. Cranked it up and let it idle. The fluid seemed to be coming through at a slow ooze at best. Does anyone have a video inside the radiator with the radiator cap off while its running so I can compare to mine?
 

·
Registered
Joined
·
10 Posts
Did you ever get this figured out? Mine is doing the same thing. Im worried its the head gasket. Have you tried replacing water pump?
 

·
Registered
Joined
·
59 Posts
Discussion Starter #8
when I said that the fluid is coming through at a slow ooze, I meant flowing very slowly in the radiator when I checked it with it being a few inches low on fluid in the radiator.
 

·
Registered
Joined
·
10 Posts
I was having the same problem. Yesterday i filled coolant up to the fill line in the overflow. Drove it all day and it never got hot
 

·
Registered
Joined
·
59 Posts
Discussion Starter #11
Thermostat ?
I've read in different places that

1. these do have thermostats.
2. these do not have thermostats.
3 that the ones intended to be sold up north do not and the ones intended to be sold in the south or southwest do.

Does anybody really know?
 

·
Premium Member
Joined
·
3,149 Posts
660’s do not have thermostats from facrory, 450’s&700 do


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
59 Posts
Discussion Starter #14
660’s do not have thermostats from facrory, 450’s&700 do


Sent from my iPhone using Tapatalk
660’s do not have thermostats from facrory, 450’s&700 do


Sent from my iPhone using Tapatalk
Brian and HighDezRhino, thanks.

Still looking for a video of the water flowing in the radiator so I can compare it to mine. I don't think mine is pumping very well. Everything I have read says that when the Rhino water pump fails it will start leaking. Mine is not leaking but it sure doesn't look like there is much flow to it.
 

·
Premium Member
Joined
·
3,149 Posts
Make sure the weephole on bottom of waterpump is not clogged up. If i remember right my 700 has a hose comming off weephole make sure the hose is not packed up with dirt


Sent from my iPhone using Tapatalk
 

·
Registered
Joined
·
59 Posts
Discussion Starter #16
Make sure the weephole on bottom of waterpump is not clogged up. If i remember right my 700 has a hose comming off weephole make sure the hose is not packed up with dirt


Sent from my iPhone using Tapatalk
Brian, thanks I will check it this afternoon. It will be this weekend before I can run it long enough to see if it gets hot. I will check water flow in the radiator after checking the hose today.

thanks again,
Trav
 

·
Registered
Joined
·
59 Posts
Discussion Starter #17
After bleeding the water pump again and bleeding the top point again, We rode for a few hours today in temps around 95 and no overheating. so hooray, got that fixed. thanks for the help. I am still going to look at the seep line and will continue to make sure to keep the radiator clean.

I saw a youtube video where a guy bought a watering wand and made a cool tool for cleaning the radiator. He cut the end off and flattened the the rest of the the wand so it would fit between the oil and water radiators. then he rolled the end over and squeezed it to seal it somewhat. I think I am going to JB Weld it. Then drilled several holes on one side. It looked like it worked well.
 

·
Registered
Joined
·
159 Posts
you need to get the factory shop manual. it has a good troubleshooting chapter . I bought one when I bought my 660 in 2013. that's if you plan on keeping it any length of time.
 
1 - 19 of 19 Posts
Top