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Aparator

Quick question

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Hi all. A quick question about the cooling systems. 

 

I bought a 1999 800fi. A little wiring had been done, a power commander installed. The fan for the radiator had been wired up to a toggle switch. I wired it back to stock. I'm just wondering if the fan is meant to kick on when the key is turned to 'on'. 

 

There was also a fan hooked up to a toggle over the heat sink under the seat on the left (ecu?). Why would someone do this? 

 

Thanks guys

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1 hour ago, Aparator said:

 

I bought a 1999 800fi. A little wiring had been done, a power commander installed. The fan for the radiator had been wired up to a toggle switch. I wired it back to stock. I'm just wondering if the fan is meant to kick on when the key is turned to 'on'. 

The Fan will normally only come on when the Ignition is On AND the Fan Thermo Switch is closed (engine high temp state).

It should not be running with a cool engine. Fan switch on is between 208 - 216degF. Controlled by the Thermo Switch in the Left Radiator.

Some people choose to wire in a bypass switch enabling the fan to turn on whenever they like.

 

As to the addition of a cooling fan under the seat! ECU's don't normally require additional cooling. Sounds like it might be for the R/R.

 

Do you have the Service Manual? You can download it from this site.

 

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The rad thermo switch should only have one wire to it if it’s the stock one. This wire is 12v+ via the fan, the switch connects to earth via the rad when it reaches the over temperature threshold this then allows power to flow through the fan motor, which will run until either the rad reaches the thermo switch reset temp OR you turn off the ignition. 
 

You can test you have it wired correctly as follows. 

1. Turn on ignition

2. Pull wire off switch

3. Touch wire to switch body

Be aware the fan draws 8amps at start up so will spark when you touch the switch body. Do it firmly & deliberately to minimise sparking.   The fan draw reduces to around 5amps once running. 
 

If someone wired up a bypass switch, normally you would create a new earth then take a wire from it to the bypass switch. Then take a wire from the original thermo switch supply wire by tapping into it somehow ( 3 way blade connector etc) to the other pole on the bypass switch. This allows bypass manual control of the fan, but it will still activate automatically if you forget ! 

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10 hours ago, Aparator said:

Hi all. A quick question about the cooling systems. 

 

I bought a 1999 800fi. A little wiring had been done, a power commander installed. The fan for the radiator had been wired up to a toggle switch. I wired it back to stock. I'm just wondering if the fan is meant to kick on when the key is turned to 'on'. 

 

There was also a fan hooked up to a toggle over the heat sink under the seat on the left (ecu?). Why would someone do this? 

 

Thanks guys

Sounds like you're in for an interesting time with this new-to-you 5th Gen.  Obviously the prior owner was fighting cooling issues (or he thought he was).  I would carefully go over the bike to insure that all of the OEM heat-handling items are in place (such as the rubber flaps over the front and rear cylinder heads).

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I rewired it to stock. The fan kicked on at 228 when I let it idle. From what I've read the running temp should be around 220 and 240 is considered high.

 

Is this an issue or normal workings for the 5th gen?

 

Rubber flaps are there, not sure about placement though, thanks for the advice.

 

From what I can see everything looks stock or at least professionally installed like the power converter. I wanted to remove the manual override because it looked as though a 5 year old threw some wire in the chassis and toggle switches in the fairings. 

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If you see *continuous* temps higher than 220ºF or below 180ºF then
trouble shooting is in order:

 

Continuous engine temps above 220ºF or 104ºC is a problem and the proper
order of items to trouble shoot are:

 

1)Faulty radiator cap... system should hold 1.1 pressure ratio...
2)Insufficient coolant...
3)Passages blocked in the radiator, hose or water jacket...
4)Air in the system...
5)Thermostat stuck closed...
6)Faulty temp meter or thermo sensor...
7)Faulty fan...
8)Faulty fan switch...

 

Engine temps below 180ºF or 82ºC is also an problem... it means that the
moisture produced during combustion is not getting hot enough to
evaporate out the pipe as steam... instead that moisture will migrate
to the oil and produce a milky white contamination...

 

Note normal by products of combustion is water... . Every gallon of gas
creates roughly 8 pounds of water vapor... we all have witnessed water
escaping out of tail pipes on cold mornings...

 

The sequence of events to trouble shoot are:

1)Faulty temp meter...
2)Thermostat stuck open...
3)Faulty fan switch... (stuck on)

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1 hour ago, BusyLittleShop said:


5)Thermostat stuck closed...

2)Thermostat stuck open...
 

 

This! ^^^^^^^^^^^^^^  (I should have mentioned this in my first post).

 

Because the VFR800's thermostat is buried deep down in the "V" of the engine it's a difficult item to remove and replace.  This problematic location causes a lot of VFR owners to defer any maintenance on it, and now the 5th Gen VFRs are over 20 years old.

 

I own two 5th Gen VFR800s, a '99 and an '01.  I replaced the thermostat on both bikes right after I purchased them because on both bikes the thermostat was original, which means they were 20 years old.

 

In the time I've been paying attention to 5th Gen VFRs (and occasionally purchasing them) I've read about a lot of cooling issues.  It appears that a 5th Gen thermostat can fail in the fully-closed position, fail in the fully-open position, and the thermostat can also fail in a way that results in a reduced range-of-motion (never going fully-closed or fully-open).

 

If this new-to-you VFR is running on the hot side there's a good chance the 20-year-old thermostat isn't moving like it used to.  And your prior owner was "slapping bandaids" on the situation with his ridiculous radiator fan switch.

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1 hour ago, Aparator said:

The fan kicked on at 228 when I let it idle. From what I've read the running temp should be around 220 and 240 is considered high.

 

 

That is too high for the fan. 220 is the upper limit for that IMHO. Running temp is getting into the danger zone at 225. That is unless you like cracking cylinder heads. The fact that it turns on, but late tells me the fan switch sensor is bad. I've seen quite a bit of variation in dash temp readings. Best to confirm with a heat gun near the exhaust port on the head itself and/or at the coolant outlets to the thermostat. Use that info to determine how accurate your dash reading is, and maybe replace that sensor as well.

 

Heat guns are cheap compared to heads.

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FWIW, the 5th, 6th, and now 8th gens. I have owned all had the fan come on at 221 degrees.  

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