Should I replace the thermostat?

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Whats the Yellow stuff? I've only seen green and orange. And you don't want orange.
What was your mixing ratio. Exactly 50/50. If you are heavy on the antifreeze that could slow down the heat disipation.
It was Orange. Don't think I want to go there after reading all the posts concerning which is best. Mix 50/50.

 
Just for good measure take the radiator cap off and let the system vent. Even though the system is vented from the water pump, it's possible to still have an air bubble trapped somewhere. My GEN I always ran at two bars on the highway even after a coolant flush. BTW -- Honda premix coolant is your friend.--G
+1

That's what I was thinking...burp the system.
Funny I get to use the same picture I posted in another cooling system thread twice in one night, but how come I never read anything about anyone using the correct "burping" procedure for the Gen I Feej.....

1156_waterpump.gif


I direct your attention to Part #33...the air bleed bolt in the thermostat. Since air is lighter than coolant, any air trapped in the cooling system will alway rise to the highest point in that system....which just so happens to be the thermostat on a Gen I, so when you fill the radiator, crack the air bleed bolt on the thermostat and fill the system until coolant starts to run out the bleed bolt. The thermostat is higher on the bike than the radiator cap, so removing the radiator cap to "burp" air out of the system doesn't work on the Gen I, since any air trapped in the system will be above the radiator cap.

You don't need to remove the bolt completely....it can get messy fast....just loosen it so air can leak past the threads until coolant oozes out. Once coolant shows up, you quit putting in coolant, tighten the bleed bolt, put the radiator cap on, make sure the overflow tank is filledl to the halfway point (you DID dump that old coolant too, didn't you?), then go drive the bike for at least five miles.

That will bring the bike completely up to temp and any residual air left in the system, which should be VERY minimal using the air bleed, will have been forced out of the system into the overlfow bottle. When you get back home, shut the bike off and let it cool down for a while, check the level on the cooolant tank. If it's low, top it off.

You shouldn't have to add any to the radiator through the cap at this point. In fact, you really don't want to take the cap off again until the next flush, using only the overflow tank to add coolant to your system. Any popping the radiator cap off will simply introduce air back into the system that must be forced out again during the next heat/expansion cycle.

edited to add: The Gen II thermostat is mounted directly to the radiator cap assembly, so there is no air bleed screw on it.

Thanks. This I didn't know.

 
David, something that comes to mind. If you flushed the system with straight water several times then drained and put in 50/50 anti-frezze, I would think your mix would be somewhat diluted as some water is going to remain in the block/oil cooler, etc.

You may want to check the mix, to make sure its actually at 50/50 (especially as to where your located in the colder climate). Worse case scenerio, drain and refill once or twice with a known pre-mix of 50/50. This probably won't help the additional heat your building but may prevent a frozen block.

I checked my shop manual and didn't see anywhere where it says to loosen the upper bleed screw (shows the bolt) when changing out the anti-freeze...

Scott

 
I'm willing to bet it's just air in the system. Happens all the time when you flush any closed loop hydro unit, be it vehicular or residential (boiler). Ask any HVAC man how many times homeowners have induced air into one of these. :lol:

Granted they may not tell you to use the bleed screw, but it's designed into these systems for just that reason.

Maybe they don't want folks to know.. Keeps the service departments working.

Far as flushing w50/50? Just go straight antifreeze, then use 50/50. It's more anal than critical believe me. ;)

:jester:

 
I have an 05 and I've changed coolant several times without "burping" the system using the bleeder screw. Top off the system at the radiator cap and leave the cap off. The rad cap is the highest point in the cooling system (or close to it) so most of any air trapped will escape there. Start the engine and let it get hot (you can feel the hoses by the water pump). Some air will bubble up and you'll see it at the rad cap. Put the cap back on and fill the coolant recover tank to the first mark. After several heat up/cool down cycles air bubles that are left will be sent to the coolant recover tank. Adjust the coolant level at the recover tank. Hope this helps.

 
I checked my shop manual and didn't see anywhere where it says to loosen the upper bleed screw (shows the bolt) when changing out the anti-freeze...
You're 100% absolutely correct. It isn't mentioned anywhere in the Factory Service Manual. Does that mean you shouldn't do it? Nowhere in the factory service manual does it say anything about the Barbarian Jumper Mod either.

 
To the OP; you're fine. Everything you state is within normal parameters. I'm guessing your recollection between pre and post is a little fuzzy and the difference isn't that much, if any.

 
Cripes!!! Whatever happened to Jestal? We need solid advice from an automotive engineer, not ramblings from an ijut who grenaded his motor and is in the radio business!

Constantmesh is right on here.

Folks, there is no reason whatsoever to mess with that bleed screw that 'Howie brought attention to. The system bleeds itself. Period.

Now, as for all the comments of different brands of antifreeze, or even mixing ratios having any discernible affect on the cooling system I call BULLSHIT!!!.

In terms of cooling properties, it's all the same!!!

As for the OP's problems, are you sure it's not your brain, and not the bike? When does it got to 4 bars more how often? In what situations? What happens when it hits 4 bars? I suppose you could have a bad T-stat that is slow to open, or possibly a bad temperature sending unit? But I wouldn't worry about it too much.

Nowhere in the factory service manual does it say anything about the Barbarian Jumper Mod either.
And peeps shouldn't be doing the BJM either!!! There's a (good) reason Yammie doesn't want the layman to know how to do it.

 
Folks, there is no reason whatsoever to mess with that bleed screw that 'Howie brought attention to. The system bleeds itself. Period.

Nowhere in the factory service manual does it say anything about the Barbarian Jumper Mod either.
And peeps shouldn't be doing the BJM either!!! There's a (good) reason Yammie doesn't want the layman to know how to do it.
You quite succinctly said people SHOULDN'T be doing the BJM. Are you also saying you SHOULDN'T use the bleed screw? Or are you just saying it isn't necessary?

Oh, don't forget I didn't grenade my motor...a broken spring did.

 
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David, something that comes to mind. If you flushed the system with straight water several times then drained and put in 50/50 anti-frezze, I would think your mix would be somewhat diluted as some water is going to remain in the block/oil cooler, etc.
This is the reasoning behind doing the blow job method, to get the extra water out of the system. OP did say blow job. If done correctly no water will remain in the system.

 
Are you also saying you SHOULDN'T use the bleed screw?
Oh, don't forget I didn't grenade my motor...a broken spring did.
Correct. I wouldn't recommend messing with the bleed screw. There is no reason to. Not only is it a pain to get to, but why introduce a possible point of failure when it not necessary?

Oh, and Merry Freaking Christmas, you grenader of engines. (Spring my butt!)

:fuck:

David, something that comes to mind. If you flushed the system with straight water several times then drained and put in 50/50 anti-frezze, I would think your mix would be somewhat diluted as some water is going to remain in the block/oil cooler, etc.
This is the reasoning behind doing the blow job method, to get the extra water out of the system. OP did say blow job. If done correctly no water will remain in the system.
Doing the blowjob DOES NOT remove all the water.

That is why I don't flush with water anymore. Just blow out as much of the old coolant as possible, and replace with the Honda pre-mix stuff.

 
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For the tool junkies (like me), page 28 of the January 2010 issue of Motorcycle Consumer News has a review of the uView 550000 system for evacuating and filling cooling systems. Sounds like it would be highly effective at getting every bit of old coolant out and every bit of air out when re filling. MSRP is $186.43; if I get one, I'll definitely be doing an online search for a better price.

 
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