Gl1500 Thermostat replacement


Information and questions on GL1500 Goldwings (1988-2000)
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eightball1013
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Motorcycle: 1998 Gl1500 SE

Gl1500 Thermostat replacement

Post by eightball1013 »



I have been reading the repair manual on replacing the thermostat, and it says to remove the radiators, lower plastics accumulator for cruise control. I see nothing about going from the top side as I read on goldwingdocs! Nothing about removing the carbs. Thanks!


eightball1013
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Joined: Tue Jul 19, 2022 10:37 am
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Motorcycle: 1998 Gl1500 SE

Re: Gl1500 Thermostat replacement

Post by eightball1013 »



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Rambozo
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Re: Gl1500 Thermostat replacement

Post by Rambozo »

It depends on why you are going in there. Often it is for leaks from the various tubes and hoses that connect to the thermostat housing. The OEM thermostat itself practically never fails.
eightball1013
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Re: Gl1500 Thermostat replacement

Post by eightball1013 »

I am going there because it never reaches operating temperature, unless I am stationary. I have a feeling its stuck open in failsafe. if its 76-90 degrees it does reach normal. If its 60 it will never reach operating temperature. it seems to me it should be able to maintain normal temperature in any atmospheric temperature. Today its 70 here, and on highway was not reaching normal temperature. But sitting in Walmart today idling the fans finally kicked on after 5 minutes. No leaks! Thank God! I am a NEW GL1500 owner, so I know virtually nothing about the quirks. I feel like even in 30 degree weather the thermostat should stay closed and regulate the temp to normal. Thank you for the reply!!
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4given
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Re: Gl1500 Thermostat replacement

Post by 4given »

How do you know it’s not reaching operating temperature?
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eightball1013
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Re: Gl1500 Thermostat replacement

Post by eightball1013 »

the gauge says below normal and barely off needle. Plus, when I open the lower vents zero noticeable heat comes out, and when idling it does climb to normal/3/4 and fan kicks on. Do these not normally run on in normal on the gauge on the highway in 60–75-degree weather? I would think in 30-degree weather the engine temp would rise to normal if thermostat was not stuck open? Are these just cold blooded?? I ride a lot in spring and fall in cool temperatures, right now it makes no difference its deep summer. For one last example if I am in a parking lot Guage shows 3/4 and Fans come on! then on the highway even now they drop below normal on the gauge even in 70-degree weather. Maybe thermostat is fine, just seems like I should have noticeable heat off valve covers like in parking lot and I would think no matter what temp it would rise to normal like a car??
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4given
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Re: Gl1500 Thermostat replacement

Post by 4given »

If the fans kick on and the gauge goes back to normal or what you think is below normal, that’s normal in my opinion. Mine runs somewhere between 1/4 and 1/2 in 50 to 70 degree weather.
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ct1500
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Re: Gl1500 Thermostat replacement

Post by ct1500 »

The thermostat is 180 degrees and is about 1/4 gauge upon opening and stays there when going down the road with sufficient heat transfer through the radiators. Fans kick on at about 210 degrees via the temp switch and is about 3/4 on gauge.
With your hand on lower radiator hose and started cold when you feel heat from the hose, that is the thermostat opening allowing hot coolant to circulate. Look at the gauge and see where you are.
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FM-USA
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Re: Gl1500 Thermostat replacement

Post by FM-USA »

eightball1013 wrote: Fri Jul 21, 2023 1:29 pm I have been reading the repair manual on replacing the thermostat, and it says to remove the radiators, lower plastics accumulator for cruise control. I see nothing about going from the top side as I read on goldwingdocs! Nothing about removing the carbs. Thanks!
Been there and found it MUCH easier and more efficient to pull the Carbs.
While you're in there you can inspect almost all the vac hoses, your bikes age is due for some.
Also near the thermostat housing there's a ground wire connection, that also should be inspected and more then likely cleaned.
IF you're going in from the top, PM me for a special replacement part info. ;)

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When I do one thing, I'll side-step a little & learn few more things.
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Swagonmaster
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Re: Gl1500 Thermostat replacement

Post by Swagonmaster »

eightball1013 wrote: Fri Jul 21, 2023 5:13 pm the gauge says below normal and barely off needle. Plus, when I open the lower vents zero noticeable heat comes out, and when idling it does climb to normal/3/4 and fan kicks on. Do these not normally run on in normal on the gauge on the highway in 60–75-degree weather? I would think in 30-degree weather the engine temp would rise to normal if thermostat was not stuck open? Are these just cold blooded?? I ride a lot in spring and fall in cool temperatures, right now it makes no difference its deep summer. For one last example if I am in a parking lot Guage shows 3/4 and Fans come on! then on the highway even now they drop below normal on the gauge even in 70-degree weather. Maybe thermostat is fine, just seems like I should have noticeable heat off valve covers like in parking lot and I would think no matter what temp it would rise to normal like a car??
I have noticed on my bike that the temp gauge reads noticeably lower in cool weather, I'm just glad that it never looks like it will overheat!
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eightball1013
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Joined: Tue Jul 19, 2022 10:37 am
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Motorcycle: 1998 Gl1500 SE

Re: Gl1500 Thermostat replacement

Post by eightball1013 »

Sounds like these bikes are cold blooded. It was 65-70 degrees this weekend and going down the highway it was barley of cold. But it would come right up to 3/4 and fan would kick on if stationary for even 3 minutes. It still bothers my OCD BC I feel like it should run in normal even in 30-degree weather like a car! lol. I do drive in 30-degree weather. Oh Well
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4given
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Motorcycle: 1996 Honda GL1500 Aspencade

Re: Gl1500 Thermostat replacement

Post by 4given »

eightball1013 wrote: Wed Aug 09, 2023 10:06 am Sounds like these bikes are cold blooded. It was 65-70 degrees this weekend and going down the highway it was barley of cold. But it would come right up to 3/4 and fan would kick on if stationary for even 3 minutes. It still bothers my OCD BC I feel like it should run in normal even in 30-degree weather like a car! lol. I do drive in 30-degree weather. Oh Well
Honda must be doing something right. Some of these 1500s get hundreds of thousands of miles on them. 👍
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Rambozo
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Re: Gl1500 Thermostat replacement

Post by Rambozo »

The thermostat cycling point is about 1/4 on the gauge. The fan cycling point is about 3/4 on the gauge. The motor should run between those two.


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