Things to check before I replace the thermostat???

[SDS]

I have a '98 Tourer with 60,600 miles on the odometer.  I have had the bike for about two years now.  While riding last week the oil temp light started flickering.  At first I thought I had imagined it but a dipstick temp. gauge was showing in the 220 degree range.  The next day the same thing happened but this time the temp was hovering at 220-225 while at highway speeds in ambient temps of about 85 degrees.  When I got home I parked the bike and attached a Battery Tender like I always do and checked the coolant levels (full).

Later that night I checked the bike but the battery was nearly dead.  I checked the connection to the Battery Tender and it was fine.  I left it for another day with no improvement in the battery level.  I removed the battery and had it checked.  I was told that it had several bad cells so I have replaced it. 

I assume that the battery issue is separate from the overheating problem but want to bounce this off of people smarter than myself before I presume anything.  Anything else I need to check before I replace the thermostat???

SDS

[Momz]

Oil temps in the 200-220 range at 85 degree ambient temp at highway speeds is very good.
Don't create a problem where there is none.

[SDS]

This is about 20-30 degrees warmer than what it has been running and I've never had the temp. light come on before now.  Any idea why the temp. would increase or why the warning light would come on if this is within the normal range? 

Also, the temp. of 220 is what is "indicated" by the thermometer but I have not verified that it is working properly. 

SDS

[Momz]

You have an "oil level" indicator and a "Temp" indicator. Valks don't come with "oil temp" indicators.

You also said that your battery is dieing; that would lead me to believe that not only is the battery sulfated, but you may also have a corroded ground wire. After replacing your battery, check that your alternator is charging properly (output at 2500 RPM should be near 14.5 volts).

[SDS]

It was the "temp" indicator light.  The one on the left.  My mistake.

I could find no corrosion on any of the wires but have not checked the alternator output. 

SDS

[Black Dog]

What Momz said...

Also, here is something to consider...  A write up I did a few years back, when I was having issues with a flickering 'over temp' light.

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I've had the same problem for a few years...  My '97 Standard would have the 'Hot' light flicker, at just about the same time my fan would kick in.  Checked along side another Valk, with one of those temp guns, and found my cooling system working just fine...  Fan was working just as it should, but kept getting the 'Hot' light.

Don't know who it was, but someone posted on the Tech Board, that early Valks (I know the '97, for sure), had an extra part as part of the cooling circuit, called an 'Indicator Unit'...

Here is the part number (I ordered mine from Dillon Brothers).  Don't know what year you've got, but use the part number, and see if it matches a part for your year Valk.

Order:
Qty.    Part Number    Price Per Item    Special Order    Product Name
----    -----------    --------------    -------------    ------------
1    38710-MZ0-003    $50.99        No            Honda - INDICATOR UNIT

It is located behind the right side cover, and is a 'plug n play' deal.

Fixed my issue, and if you have an earlier Valk, should fix yours.

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Black Dog

[SDS]

Sweet!  I'll check that out.  It sure wouldn't hurt my feelings a bit if that is all it turns out to be.

Thank you,
SDS

[Daniel Meyer]

Yeah 220 is well within normal on the dipstick. Possibly the low voltage was also an issue for the light or fan. Now that the battery's replaced may want to try it again.

[SDS]

Daniel, I think I'll take it out tomorrow afternoon to see how it does before I order any parts.  I don't mind replacing anything that needs it but don't really want to start spending money I don't have to. 

Assuming the dipstick thermometer is operating properly what would be the high end of normal operating temps that you guys would feel comfortable with?

SDS

[Daniel Meyer]

Mine seldom goes above 230...but 250 wouldn't bug me if I was sitting in traffic and hearing my fan cycle...

Pushing hard but moving I expect around 220...

[SDS]

Thanks.  Mine has typically stayed just below or right at 200.  Again this is assuming the thermostat is reading properly. 

SDS

[Ricky-D]

The thermostat is not a maintenance item and shouldn't be in a replacement schedule.

Over the years, there has been very little posted about the thermostat failing in the Valkyrie.

I would caution about replacing the thermostat due to the nature of bolts seizing up in the aluminum.

The bolts that hold the thermostat housings have been untouched since the bike was manufactured and can represent a very real problem with removal attempts.

***

[F6Dave]

Early Valks used a separate temp sensor mounted by the thermostat, and a switching unit behind the left side cover that read the voltage from the sensor and turned the light on if it was too hot.  Later models (and maybe all Interstates, I don't remember for sure) combined the switch with the temp sensor, and eliminated the unit under the side cover.

It is VERY common for the switch  under the cover to fail.  It is a simple plug in replacement.

Some (including me) have upgraded to the later unit and eliminated the crummy switch.  The threads of the combined unit are the same as the old temp sensor and it costs less.  You just need to change a connector and make a simple jumper where the old unit plugged in.

[SDS]

Yesterday I was able to get the bike out and go riding for a little while.  I was only able to go about 50 miles but everything seemed fine.

I rode almost entirely highway miles (same as the last time it was overheating).  Air temp. was 86 degrees, driving right around 65mph.  Oil temp stayed right around 220 (+/- 5deg) during the ride after it came up to temp.  When parked the fan kicked on in a timely manner and seemed to be working fine. 

I don't understand how the battery problem would have caused the temp. sensor problem but it appears as though changing the battery has solved the problem....for now at least.

I'll do some more riding over the next few days to verify that there is not still a problem.  Thank you guys for all of the input and advice.  I don't mind doing some repairs myself but I'm really glad I asked before tearing into the scooter unnecessarily. 

SDS

[F6Dave]

SDS, I should mention that when my indicator unit began to fail the flickering was very intermittent and random.  There didn't seem to be a pattern at all.  It would flicker after a few miles on a cool morning, or after several hours on a 95 degree day.  It would occur several times in a few days, then disappear for weeks.  There have been many posts here about the same problem, and the random flickering along with normal operating temps seem to be the common thread.

Since you've checked out the cooling system temps I wouldn't worry.  The part is only about $40 but certainly can wait as the flickering is only mildly irritating.

[SDS]

F6Dave, thanks for that.  I'll keep an eye on it.  I hate it when things like this happen.  It makes me leery of taking trips very far from home out of fear of something happening when I don't have a way to take care of it. 

I really appreciate everyones help with this.

SDS