NEW thermostat stuck open?
- Thread starter JimGregory
- Start date
Actually, that's a very good straw... there are reports of those having issues.
OP
OP
I don't know of a temp sensor on the radiator but the one peeking it's nose in the back of the thermostat housing I can see. It looks like a master workout to get to that connector?
Is there also a block temp sensor? My manual is in the frozen garage at the moment.
Is there also a block temp sensor? My manual is in the frozen garage at the moment.
There's a ground connector here you want to make sure is in good shape and clean.
Great pics from John here:
https://www.st-owners.com/forums/sh...lant-Thermostat-Starter-Valve-Synch-amp-Other
I can't remember if that will cause a faulty read on the temp bars... I seem to recall there's another sensor or connector somewhere... searching.
Great pics from John here:
https://www.st-owners.com/forums/sh...lant-Thermostat-Starter-Valve-Synch-amp-Other
I can't remember if that will cause a faulty read on the temp bars... I seem to recall there's another sensor or connector somewhere... searching.
This person had an issue with the ECT (Engine Coolant Temp) sensor... it doesn't sound like the same as yours but it's possible you're just getting the other end of the spectrum for that sensor failing:
https://www.st-owners.com/forums/showthread.php?41360-Temp-problem
Item 22 here:
http://www.cheapcycleparts.com/oemparts/a/hon/5053f075f870021c54be6245/water-pipe
$20 isn't bad but you'd have to get to the back of the thermostat housing.
It doesn't look like this is a common failure on the site so maybe just disconnecting it and reconnecting/cleaning the connection is good enough.
https://www.st-owners.com/forums/showthread.php?41360-Temp-problem
Item 22 here:
http://www.cheapcycleparts.com/oemparts/a/hon/5053f075f870021c54be6245/water-pipe
$20 isn't bad but you'd have to get to the back of the thermostat housing.
It doesn't look like this is a common failure on the site so maybe just disconnecting it and reconnecting/cleaning the connection is good enough.
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Yes, I was going to chime in a few minutes ago with my [perhaps faulty] recollection that bad wiring to or corrosion on the ECT sensor terminal or the corresponding thermostat housing ground wire gives a faulty high temperature reading, not a low temperature reading.
OP
OP
Thanks guys for the research. Pretty sure I have read all there is to read. (Except ALL of the service manual instructions DUHH!!) Admittedly though this is the first vertically oriented thermostat I have ever run into. That's my excuse and I'm sticking to it.
The problem of course, is I also forgot most of what I read!
What I KNOW is that I installed the new thermostat improperly.
What I DON'T know is what happens when you install the thermostat improperly. It IS called the bleed hole. It should be on top. The temp sensor is also on top. HMM..
What else I DO know is, that IF there are air pockets in the cooling system the sensor will indicate low temps when an air bubble hit's it. (This is what I am banking on)
I don't know what kind of contortions one needs to go through to touch the coolant temperature sensor and check the connection etc. Looks nightmarish.
The fact is I installed the thermostat wrong. I should install it properly, and check it out right?
Also what turns the fans on and off? I know there are relays but I don't know where it gets the signal from. The engine computer? And where does IT get it's info from. Must be the coolant temp sensor.
Also what do you suppose the ground to the thermostat housing actually does? The housing is not naturally grounded so it is not supplying a ground. It's receiving a ground.
All I can figure is it's a dissimilar metals thing and/or corrosion protection. AHHH...it's supplying the ground for the temp monitor!
Dave somewhere you mentioned a multiple ground point under the dash. I should probably check that out long as I am in there. The HID wiring may have touched on that and I just tore all that out.
The problem of course, is I also forgot most of what I read!
What I KNOW is that I installed the new thermostat improperly.
What I DON'T know is what happens when you install the thermostat improperly. It IS called the bleed hole. It should be on top. The temp sensor is also on top. HMM..
What else I DO know is, that IF there are air pockets in the cooling system the sensor will indicate low temps when an air bubble hit's it. (This is what I am banking on)
I don't know what kind of contortions one needs to go through to touch the coolant temperature sensor and check the connection etc. Looks nightmarish.
The fact is I installed the thermostat wrong. I should install it properly, and check it out right?
Also what turns the fans on and off? I know there are relays but I don't know where it gets the signal from. The engine computer? And where does IT get it's info from. Must be the coolant temp sensor.
Also what do you suppose the ground to the thermostat housing actually does? The housing is not naturally grounded so it is not supplying a ground. It's receiving a ground.
All I can figure is it's a dissimilar metals thing and/or corrosion protection. AHHH...it's supplying the ground for the temp monitor!
Dave somewhere you mentioned a multiple ground point under the dash. I should probably check that out long as I am in there. The HID wiring may have touched on that and I just tore all that out.
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Dave.David
Rider
What about the radiator it self, can be a bit clogged, need a flush.
Don B
The first sentence in Jim's first post: "Just went through the whole rigamarole..flush coolant blablabla.. New honda thermostat."
Mechanically... everything seems good, both the old and new t-stats open at the correct temp and most failed t-stats will fail open so it's pretty obvious that you have a bad one. Some have stuck a little then unstuck after more cycles but most fail open... so, you get the 3...2..1... no bars with the bike moving due to the air cooling the water in the radiator and engine... but, since these appear to be mechanically okay.. then something electronic is going on. If the radiator had blocked issues.. well, not sure what that would do.. I know one test for a bat t-stat was to block the radiator w/cardboard and ride it a short distance to see if the blocked radiator would let the bike get to 3 bars but I never liked that test due to possible overheating if the issue was electronic.
So, to me it's got to be a bad/cut/corroded wire/connector somewhere... and then if not, the sensor itself.
So, to me it's got to be a bad/cut/corroded wire/connector somewhere... and then if not, the sensor itself.
Couple of tricks I've learned over the years doing thermostats. Gorilla Snot is your friend, they call it trim adhesive at the parts house, a little bead of that on the thermostat seal and on the thermostat, let it set up, put the thermostat in place, and no fally outy.....
Headliner adhesive: great for those pesky gaskets that sit on the vertical, both o ring type and paper, give the gasket and surface a spritz, let it set up, install the gasket, and bob's your uncle....
And the kicker: Aspirin. Especially useful for vehicles that always seem to have that air lock at the thermostat. Open the thermostat, pop an aspirin in the openening , two actually, opposite each other. Install the thermostat, fill and run. The aspirin will eventually dissolve, generally after the air has cleared, and no headaches.
My garage always has gorilla snot and headliner cement in it.....somewhere, I usually end up with 2 or 3 cans, because I never remember to put it back on the shelf. I'm so ashamed........My garage looks like several cars, a couple of motorcycles and a mower or two just exploded......
Headliner adhesive: great for those pesky gaskets that sit on the vertical, both o ring type and paper, give the gasket and surface a spritz, let it set up, install the gasket, and bob's your uncle....
And the kicker: Aspirin. Especially useful for vehicles that always seem to have that air lock at the thermostat. Open the thermostat, pop an aspirin in the openening , two actually, opposite each other. Install the thermostat, fill and run. The aspirin will eventually dissolve, generally after the air has cleared, and no headaches.
My garage always has gorilla snot and headliner cement in it.....somewhere, I usually end up with 2 or 3 cans, because I never remember to put it back on the shelf. I'm so ashamed........My garage looks like several cars, a couple of motorcycles and a mower or two just exploded......
Dave.David
Rider
I get the gorilla snot, love it. Use to put it heavy on one side of valve cover and could pull valve cover off and on all day run after run..
But aspirin? Lol
Permatex used to have a spray gasket adhesive - basically a thick contact cement, but no doubt the trim adhesive is a lot cheaper.
OP
OP
I don't think this application calls for any adhesive. The O ring should do the job.
So upon further investigation it seems that depending on how you spin the thermostat around there feels like the occasional interference with something inside the housing. This would certainly be not good if it's true. It's hard to tell what's going on back there though. With the bleed hole at 12:00 and some few degrees either way it's definitely clear.
So re assembled. Ran. Topped off. etc..installed plastic. ran.. Cant ride it as there is snow everywhere. Supposed to melt tonight in the warm rain. We'll see.
Was playing with my point and shoot laser infrared thermometer on the radiator. Which seems very accurate or at least repeatable. For the price anyway.
The fans turn on at about 220f. Then 10 seconds later they turn off at just under 200. This is with the thermometer pointing at either side tank of the radiator.
I though that is pretty remarkable. 20 degrees in 10 seconds.
I wish I could hook up my engine code reader scanner to this bike. It gives me a wealth of real time information. Well everything the engine computer see's anyway.
So upon further investigation it seems that depending on how you spin the thermostat around there feels like the occasional interference with something inside the housing. This would certainly be not good if it's true. It's hard to tell what's going on back there though. With the bleed hole at 12:00 and some few degrees either way it's definitely clear.
So re assembled. Ran. Topped off. etc..installed plastic. ran.. Cant ride it as there is snow everywhere. Supposed to melt tonight in the warm rain. We'll see.
Was playing with my point and shoot laser infrared thermometer on the radiator. Which seems very accurate or at least repeatable. For the price anyway.
The fans turn on at about 220f. Then 10 seconds later they turn off at just under 200. This is with the thermometer pointing at either side tank of the radiator.
I though that is pretty remarkable. 20 degrees in 10 seconds.
I wish I could hook up my engine code reader scanner to this bike. It gives me a wealth of real time information. Well everything the engine computer see's anyway.
Blrfl
Natural Rider Enhancement
Agreed. Torque both bolts gradually and evenly and the O ring will seal just fine.
If I remember the inside of the housing correctly, it's not completely empty and there are a few protrusions that the thermostat could get snagged on of not inserted the right way. They might even be there to limit the amount the thermostat could rotate to keep the bleed hole in a close to the right position.
The FI system in the ST isn't particularly sophisticated, but it's pretty good about complaining when it thinks something is wrong and the diagnostic procedures in the service manual are decent.
I'd welcome an OBD-style interface on my motorcycle, but it's not going to happen unless governments start mandating it. That's how we got what we have now.
--Mark
OP
OP
Yesterday morning it was 10f and roads all salty and icy. My driveway was ice.
Rained all night and this morning it's 41f on it's way up with clear washed roads. Think I will ride to work!
EDIT: Rode to work. All seemed normal. Average fuel consumption (no highway) 32mpg.
Rained all night and this morning it's 41f on it's way up with clear washed roads. Think I will ride to work!
EDIT: Rode to work. All seemed normal. Average fuel consumption (no highway) 32mpg.
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Like I said....I have found a few of them turned slightly and mounted incorrectly, causing damage to the inside of the T-stat cover, and causing the same problems you were having.
Once removed, inspected, and replaced correctly, the problem was gone.
Sorry Dave, but just because you have not seen it happen, does not mean it does not happen
Once removed, inspected, and replaced correctly, the problem was gone.
Sorry Dave, but just because you have not seen it happen, does not mean it does not happen
Your mpg sounds low. Was that what you were averaging before? Or did you simply ride all the way wide open?
OP
OP
Ya sounds low to me as well. That was babying it. The way home I rode quite a bit, being very sedate. Just 40 on the highway. Mid 30's on secondary roads.
Other then that all seems normal enough. I don't ever remember getting better then low 40's on highway, but I havent had it all that long. I did double the mileage though.
Other then that all seems normal enough. I don't ever remember getting better then low 40's on highway, but I havent had it all that long. I did double the mileage though.