Suction hose from a Vacuum cleaner


Information and questions on GL1500 Goldwings (1988-2000)
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PedroTQ
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1988 GL-1500

Suction hose from a Vacuum cleaner

Postby PedroTQ » Sun Jan 25, 2015 3:06 pm



Gooday to All,

I am just wondering if I actually need that vacuum cleaner suction hose going from the exhaust manifold to the air intake box ???

I understand that in the United Stated the weather gets very cold but here in the Oz it never gets down to freezing maybe down to 5 deg C

I am hoping "redial" from South Oz will have an answer. Maybe I will just take mine off and see how I go, as it goes through such a tortuous path, looks ugly, a pain to refit and serves little purpose :?:

Regards, Peter.


#1 - 1975 GL-1000 - showroom
#2 - 1976 GL-1000 - sidecar
#3 - 1978 GL-1000 - parts
#4 - 1975 GL-1000 - parts, but had the sidecar
#5 - 1978 GL-1000 - project with grandson (secret parts source)
#6 - 1988 GL-1500 - Flagship!
#7 - 1998 GL-1500C - Valkyrie

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ct1500
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Re: Suction hose from a Vacuum cleaner

Postby ct1500 » Mon Jan 26, 2015 8:10 am

The hot air door begins to close drawing heated air into intake at 60F and is fully closed by 50F. Heated intake air systems have been standard for close to fifty years and hardly serve no purpose. :)

Benefits include quicker warm up times, better combustion of fuel mixture, reduction of driveability problems such as stumble on accelerator application.
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redial
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Re: Suction hose from a Vacuum cleaner

Postby redial » Mon Jan 26, 2015 10:36 pm

As pointed out by CT1500, it is not so much the freezing temps that it is overcoming, but the more moderate ones as well. It just helps to keep the engine functioning at temperatures that are part of the process of keeping itself warm. I would leave it in, but that is just me.
Len in Kapunda

The world is not going to finish today, as it is already tomorrow in Australia and New Zealand, and other islands of foreign nations such as Guam and Samoa.

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silverado6x6
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Re: Suction hose from a Vacuum cleaner

Postby silverado6x6 » Tue Jan 27, 2015 7:47 am

I would leave leave it in as well, less time on the choke more fuel saved.
But if I were riding in very very hot weather I might consider taking off the lower end behind the cowl and getting a small fan like one used for a computer case, 12 volt, wire it on a switch, that's to cool the carbs so they don't boil over.
Would not be too hard I think, might have to wiggle the hose around a bit away from the duct, and fit a wire screen over it to keep bigger road debris at bay.
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702scottc
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1990 GL1500 Aspencade (sold)
2005 GL1800

Re: Suction hose from a Vacuum cleaner

Postby 702scottc » Wed Jan 28, 2015 6:11 pm

I removed mine when I was chasing a coolant leak some months back, runs just fine . Doesn't get really cold here either. Carb icing isn't something you here about much anymore.. When the thermal switch fails and it will,the engine will detonate from drawing in constant heated air and increasing Nox emissions. The auto manufacturers went away from TAC systems years ago due to that exact issue plus with the ability to control fuel trim obsoleted those systems. My 81 Interstate had no such system and it ran as good as my 1990 on cold days. Give it an extra minute or 2 to warm up and you'll be good to go.

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ct1500
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Re: Suction hose from a Vacuum cleaner

Postby ct1500 » Thu Jan 29, 2015 11:43 am

702scottc wrote:I removed mine

Fair enough
702scottc wrote:When the thermal switch fails and it will,the engine will detonate from drawing in constant heated air and increasing Nox emissions

I have worked on thousands of vehicles in my time and this very simple system has a low failure rate. The very nature of the bimetal spring in its' at rest or static position means the normal position is open for ambient temps above 60F (allowing outside air in). Any trouble of this system would in all likelihood be a failure to close at lower temps (not allowing heated air).
702scottc wrote:Carb icing isn't something you here about much anymore.

Precisely due to the many systems designed and used by all the vehicle manufacturers for proper combustion and best driveability. The 1500 has items in place to prevent fuel line vapor lock which you don't hear much about anymore either. :)
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702scottc
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1990 GL1500 Aspencade (sold)
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Re: Suction hose from a Vacuum cleaner

Postby 702scottc » Fri Jan 30, 2015 1:54 am

I've worked on thousands of vehicles as well. I've been ASE certified since 1981 on automotive and heavy truck along with a 2G emissions certification for 20 years and those simple bimetallic vacuum switches do fail. Maybe I've seen more of it out in this part of the country due to high ambients and dusty conditions. That really isn't the issue, the issue is, is it really a necessary item? In the northern latitudes it probably helps for the first few minutes of operation on cold days. Since these systems where introduced the fuel additives used and mandated by the EPA have changed significantly. Year round ethanol blended gasoline is fine in cold weather but causes a detonation problem in the summer especially out west. Having a malfunctioning TAC system just makes it worse. I've seen lots of those systems fail on cars over the years causing failed tailpipe emission tests.
The way that hose is routed around the fan motor and between the frame is a pain to get in and out. Mine is gone .




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