UPDATE ON OVERHEATING!!!!!!

[offroadchevy806]

OK, so i got a new radiator in that had a fan switch and the fan, am i just going crazy? put this on today and still over heated with NO fan kicking on. i have replaced the fan switch now twice, replaced the water pump and checked twice that the new thermostat was installed correctly. i have an auto-meter gauge on my bike with the thermo sending unit  for it in the thermostat housing am i getting higher readings since that would be where the coolant is the hottest? on the I/S where is there thermo sending unit at?

i let the bike idle for some time and the fan did not kick on, but the overheat light did and my gauge was pegged at 250!!!

most importantly my fan is not coming on!!!!!! help i am tired of messing with it,

oh and on s side note with the fan hardwired to a toggle switch my gauge reads  about 225 +or- a few degrees. 

[RP#62]

The thermosensor in all models is in the thermostat housing (as is the temp sensor for the ICM).  I know this has got to be frustrating for you so forgive my questions if you've already checked.  Have you checked the upper and lower hoses for obstructions or collapse?
-RP

[offroadchevy806]

The thermosensor in all models is in the thermostat housing (as is the temp sensor for the ICM).  I know this has got to be frustrating for you so forgive my questions if you've already checked.  Have you checked the upper and lower hoses for obstructions or collapse?
-RP

yep, checked serveral times, so i am not reading high temps with the aftermarket gauge?

[BonS]

When I installed my temp gauge I installed the sender on the bottom of the crankcase pretty much just next to the rear brake pedal. The sender for the instrument light overheat switch and the temp sensor for the ICM is on the thermostat housing. If you installed the temp gauge sender up on the thermostat housing then it likely is just hotter there.

[Valker]

Fan relay?

[offroadchevy806]

Fan relay?

what is the fan relay? is it the thermo fan switch at the bottom of the radiator?

[offroadchevy806]

The thermosensor in all models is in the thermostat housing (as is the temp sensor for the ICM).  I know this has got to be frustrating for you so forgive my questions if you've already checked.  Have you checked the upper and lower hoses for obstructions or collapse?
-RP

is this how the I/S receives the signal for the temp display

[macdoesit]

OK, so i got a new radiator in that had a fan switch and the fan, am i just going crazy? put this on today and still over heated with NO fan kicking on. i have replaced the fan switch now twice, replaced the water pump and checked twice that the new thermostat was installed correctly. i have an auto-meter gauge on my bike with the thermo sending unit  for it in the thermostat housing am i getting higher readings since that would be where the coolant is the hottest? on the I/S where is there thermo sending unit at?

i let the bike idle for some time and the fan did not kick on, but the overheat light did and my gauge was pegged at 250!!!

most importantly my fan is not coming on!!!!!! help i am tired of messing with it,

oh and on s side note with the fan hardwired to a toggle switch my gauge reads  about 225 +or- a few degrees. 

I replaced water pump on my pickup one time and it still over heated drove me nuts, the new water pump was also bad, it does happen.

[offroadchevy806]

OK, so i got a new radiator in that had a fan switch and the fan, am i just going crazy? put this on today and still over heated with NO fan kicking on. i have replaced the fan switch now twice, replaced the water pump and checked twice that the new thermostat was installed correctly. i have an auto-meter gauge on my bike with the thermo sending unit  for it in the thermostat housing am i getting higher readings since that would be where the coolant is the hottest? on the I/S where is there thermo sending unit at?

i let the bike idle for some time and the fan did not kick on, but the overheat light did and my gauge was pegged at 250!!!

most importantly my fan is not coming on!!!!!! help i am tired of messing with it,

oh and on s side note with the fan hardwired to a toggle switch my gauge reads  about 225 +or- a few degrees. 

I replaced water pump on my pickup one time and it still over heated drove me nuts, the new water pump was also bad, it does happen.

i can see circulation in the radiator

[Valker]

Fan relay?

what is the fan relay? is it the thermo fan switch at the bottom of the radiator?

Nevermind. I don't see one on the wiring diagram. I was thinking of my GoldWing. Relay went out-no fan.

[Robert]

Ok so the fan didn't kick on, with the fan on rev, the engine to 2000 rpm and hold it there for a minute or 2 does it come down and stay at 190?  If it doesnt come down could it be that the water pump you put in is not turning? Water will look like its circulating with the engine running and getting hot just by the heating of the water. To verify you could take off the cover of the pump and make sure its turning when you crank it or maybe that something happened to the impeller. With the fan on and the engine idling it should be able to take the temp down to 190 but it may take a while. Is the fan really blowing or is there not much air coming out? Does the system pressurize right away from cold start or does it take awhile?

[indybobm]

Maybe we should set the stage again.

1. How long have you had the Valk?
2. When did the problem start?
3. Did you make any repairs or modifications before the problem started?
4. Any other strange problems lately?

[offroadchevy806]

Maybe we should set the stage again.

1. How long have you had the Valk?
2. When did the problem start?
3. Did you make any repairs or modifications before the problem started?
4. Any other strange problems lately?

1. i have had her for about 2 years now
2. about a month ago, ( so i replaced the thermostat, replaced fan switch with on from ebay used, replaced the radiator assembaly that came with a fan and fan switch that work on the bike before mine,
3. no repairs or mods before the problem, but have installed the autometer water temp gauge since this has happened just to watch the temp and see when the thermostat opens.
4. no other problems, she runs like a bat out of hell and will eat up HD's all day

the upper hose is hot and the lower hose it a little cooler to the touch if this helps at all

[BonS]

. . . have installed the autometer water temp gauge since this has happened just to watch the temp and see when the thermostat opens.

Gotta ask: Is the sender for the Autometer gauge below the engine or by the thermostat?

[offroadchevy806]

. . . have installed the autometer water temp gauge since this has happened just to watch the temp and see when the thermostat opens.

Gotta ask: Is the sender for the Autometer gauge below the engine or by the thermostat?

it is in the thermostat housing

[BonS]

And the overtemp idiot light comes on after some idling and the fan never switches on?

[offroadchevy806]

And the overtemp idiot light comes on after some idling and the fan never switches on?

thats right

[BonS]

have you changed or tested the overtemp switch?

Actually it's not a switch it is a thermosensor. The resistance of the unit changes with temperature. The manual calls for about 52 ohms @ 176F and 16 ohms @ 248F. They want you to do it in a pan of 50/50 coolant and be careful to insert the thermosensor up to its threads and hold it there for 3 minutes before taking its reading.

I'm wondering if the thermosensor is bad and the engine is not actually not overheating. The lower hole that should be used for the Autometer gauge is sensing the cooler water coming into the engine as it leaves the radiator. The top location is seeing the hottest water as it leaves the engine and heads toward the radiator. So it makes sense that the Autometer is reading scary high temps.

[Bigwolf]

Offroad,
      I keep thinking about how your whole problem started.  You said it was a busted water pump shaft that had it overheating in the begining.  I have not had an oportunity to look at the shaft of a Valk waterpump but it seems to me that something had to be really bad amiss for those drive tangs to be torn off the end of the shaft.  There must have been an extreme overload on it for that to happen so now that you are still having problems, I am thinking the water pump is still not pumping properly.  If enough force was there to break the 2 sides of the original water pump shaft, then maybe the part that drives the water pump was also cracked and has now broken off.  Or maybe it is slipping in whatever drives it.  If it was my bike, I would want to know what exactly caused the first water pump to break that way.  Because if you do not know that,  then you may continue to get screwed by whatever caused it and you will never be able to keep it working right.  I do not remember if you said or not,......was the impeller of that first pump all busted up?  If it was, then that could have locked up and caused the busted shaft.  If not, then you had something else going on that caused that water pump to lock up hard enough to break the shaft.  My manual does not show a breakout drawing of the oil pump so I do not know if the output shaft to the water pump is also the same shaft that comes into the oil pump from the chain drive on the back of the case.  If it is one shaft that goes completely thru the oil pump providing both input to the oil pump and to the water pump, then it is probably OK if the front of it (the tang) that drives the water pump is OK. 

I doubt that your current problem is electrical.  I think it is probably still a problem with the water pump or water pump drive.  It could be that the water pump is pumping some but also slipping so that it does not pump enough and if that is true, then it could also be pumping more when cold but less as it gets hotter.  I have experienced that with a car, not a Valk, but it could be the case here.

If I was not so far away from you, I would enjoy helping you run this problem down.

Wolf

[hager the horrible]

Have you checked for blown head gasket or gaskets wish i were closer as i have a coolant system tester that sniffs the radiotor for carbo dioxide in the cooling system .
Have seen more than once blown head gaskets causing such problems

[Ricky-D]

I think the problem is that you have wired your aftermarket temperature apparatus in with the over-temperature idiot light the is already standard equipment on the bike.

You have probably defeated the system parameters designed by Honda that are incorporated into the electrical system for the bike and,, that have already been touched upon by a few others in this thread.

***

[R J]

I think the problem is that you have wired your aftermarket temperature apparatus in with the over-temperature idiot light the is already standard equipment on the bike.

You have probably defeated the system parameters designed by Honda that are incorporated into the electrical system for the bike and,, that have already been touched upon by a few others in this thread.

***

 I agree whole heartedly here with Ricky-D.

Undo all the BS that you have added into the water system and see if maybe, just maybe it is not running hot, just the idiot light thinks it is.

I used the Monsen (sp) gauges from Germany and mine feels hot but it isn't.   Once when I had a small leak, the fluid got low and the idiot light flickered.  I was setting on 230+ on the gauge.     Somehow, I forgotten now, but I broke the Monson sender off the bottom of the engine and I just took the gauges off.

[BradValk48237]

Might be a dumb question, but....

Are you sure the fan works??????

Bard

[offroadchevy806]

thanks for all the replys, ok here it goes

The old water pump could barely be turned by hand like something was binding it this i think could have contributed to the water pump fork on the shaft to break. So i replaced that. I am starting to think that the water sending unit for the autometer gauge might be getting in the way of the thermostat from opening all the way restricting the flow, i have bought another thermostat the has just a slight smaller opening than the oem one, i got it off of the generic parts list on here. Another thought if just sitting at idel will it be accecptable for the bike to maintain a temp of 210 - 220 with the fan turned on with my toggle switch? what temp does the idiot light turn on at?

oh almost forgot, i dont have the gauge wired in with the idiot light, it has it own sending unit that it is wired to.

well i am going to install the generic thermostat, i guess while i am there i will go ahead and test the idiot light sending unit just to verify that it is working or not. i will post updates later this evening

[YoungPUP]

It may be worth a trip down to the local FD with a pizza and ask if they'll show you a demonstration of their thermal imaging camera with your valk as the demo subject. Then you'll have a fairly accurate picture of what the temps are over the radiator, hoses etc. Most in use now have a cross hairs that allow us to check temps at specific points.

[offroadchevy806]

OK so instead of installing the generic thermostat i figured i would just run it with out a thermostat i just wanted to remove any ristriction to the flow,

OK here is what happened

1. not thermostat, bike hit 210 according to my gauge with the sending unit that is installed in the thermostat housing (probably reading hotter than what is really is. no fan wait until temp read 230-240 then i toggled on the fan temp drops back to 210 according to the gauge. and stayed about 210-220 while idleing for about 10-15 min.

2. i toggled the switch to off temp slowly goes to 250 no fan kicks on not light turns on, 250+ the light and fan kicked on, fan shut off quickly light stayed on i toggled the fan on and it finally dropped to 220 probaly would have dropped more but just shut her off.

3. OK the fan kicks on at about 205 + or - a few degrees at the bottom of the radiator. The engine is reading about 250+  according to the autometer gauge, the overheating light is that is installed in the same housing should turn on at 240 +or- a few degrees, so i am reading hotter on the autometer gauge.


what should be about the temp difference from the bottom of the radiator with the thermo switch for the fan is located vs. the top of the motor where the over temp sensor is and my sending unit for the autometer gauge?

[sandy]

I have a Volt Ohn meter with a thermo sensor built in for testing. I've checked my radiator next to the filler and it reads 207 when the fan kicks on. It'll drop to 202 when it turns off. I have an oil temp dipstick but no other water temp sensors.

[offroadchevy806]

I have a Volt Ohn meter with a thermo sensor built in for testing. I've checked my radiator next to the filler and it reads 207 when the fan kicks on. It'll drop to 202 when it turns off. I have an oil temp dipstick but no other water temp sensors.

how do you have this rigged? i have a volt ohm meter and an extra overheating sensor, could i rig something up with this and place it in the radiator filler do catch a reading like you have?

[Madmike]

I seen that your water pump shaft was broken - what kinda shape was teh drive side in???

[BonS]

offroadchevy806 - What year is your Valk? There are two coolant temperature sender/switch circuit designs in play here:

1997-1999 models have a thermosensor that connects to a module that converts the signal to turn on the temperature light. (This is the one that varies its resistance with temperature.)

2000+ models have a simple thermostatic switch that directly connects to the temperature light. (I can't find a temperature where this switch kicks in.)

[offroadchevy806]

I seen that your water pump shaft was broken - what kinda shape was teh drive side in???

the shaft that is attached to the oil pump was in good shape, it was not cracked or bent also did not show signs of being torn up at the end that goes to the water pump. only the female end of the water pump shaft was the only end that broke, once i removed the old water pump it was very hard to turn by hand, the bearings to the water pump must have went bad then some how made it hard for the oil pump to turn the water pump shaft which then broke it

[offroadchevy806]

offroadchevy806 - What year is your Valk? There are two coolant temperature sender/switch circuit designs in play here:

1997-1999 models have a thermosensor that connects to a module that converts the signal to turn on the temperature light.

2000+ models have a simple thermostatic switch that directly connects to the temperature light.

i have a 98, in all the electric on my bike for coolant is starting in the thermostat housing, a thermo sensor that goes to the icm, another for the overheat light, (then i added a thermo sending unit for my autometer gauge in the thermostat housing drilled and tapped)so a total of 3 things in the thermo housing and the thermostatic fan switch

[BonS]

Have you tested the fan switch? I believe that others have said, and I'll echo them, that the switch comes on by 208-216 F and turns off at at 199-207 F.

With no fan running and the bike sitting still I wouldn't expect a big difference in temperature from the top of the radiator to the bottom.

[RP#62]

I've got a digital coolant temp indicator with the sensor mounted in the thermostat housing.  I drilled and tapped the boss that's there to mount the sensor.  Mine indicates about 202-205°F when the fan kicks on.  Cruising down the highway it indicates around 165°F depending on outside air temp. 

I made my sensor so I was careful to keep it short enough to not interfere with the thermostat.  If it does interfere, I think you can rotate the thermostat so that it clears.

Have you checked calibration on your temp indicator - i.e. put it in a pot of boiling water and see if it indicates 212?
-RP

[FryeVRCCDS0067]

If I'm understanding correctly. When you tested it without the thermostat in it and let it run till the fan kicked on the overheat light came on then too. Then the fan kicked off quickly but the overheat light stayed on? But, the overheat light will go back out if you manually hold the fan on?

Ignoring everything else and just looking at that I'd think that either the fan switch is not working correctly or the trigger sensor for the overheat light is not working correctly.

I'd reinstall the thermostat, remove the new sensor for the gauge you installed and replace the fan switch and the overheat light sensor. Then see what happens. But, I'd do that after I verified visually if possible that the new water pump is turning.

[Westsider]

Is the pump drive shaft turning , like mentioned above??

[offroadchevy806]

Is the pump drive shaft turning , like mentioned above??

yes it is turning

[offroadchevy806]

I've got a digital coolant temp indicator with the sensor mounted in the thermostat housing.  I drilled and tapped the boss that's there to mount the sensor.  Mine indicates about 202-205°F when the fan kicks on.  Cruising down the highway it indicates around 165°F depending on outside air temp. 

I made my sensor so I was careful to keep it short enough to not interfere with the thermostat.  If it does interfere, I think you can rotate the thermostat so that it clears.

Have you checked calibration on your temp indicator - i.e. put it in a pot of boiling water and see if it indicates 212?
-RP

ok, right now i am at work, here are a couple of questions

1. I have it installed in the same spot as you then, with the thermorstat in place and rotated looks like it interfears still, could i grind the sensor down some?

2. I am going to put the thermostat back in today when i get off of work, i am going to boil some water place my thermostat in it, the fan switch, overheat temp sensor, and for the hell of it, my autometer temp sensor, what ohm  should be read on my volt/ohm meter on each item what are the ohm vs. temp that i am looking for?

3. where should my volt/ohm meter be selected to when i am doing these test?

[BonS]

Your meter should just be set to "ohms". I don't know what kind you have - autoranging or not - but set it for low ohms such as 0-1000 if you have to.

The thermosensor should read 47-57 ohms at 176 degrees F and 14-18 ohms at 248 degrees F. If its off by more than 10% is should be replaced. They want the sensor to be immersed up to its threads and the temperature to be stable for 3 minutes or longer.

The fan switch should come on (~0 ohms) around 234-244 degrees F.
The fan switch should turn off (very high ohms) around 199-207 degrees F.

The thermostat should begin to open at 176-182 degrees F.
The thermostat should be fully open at 199-206 degrees F.

[offroadchevy806]

Your meter should just be set to "ohms". I don't know what kind you have - autoranging or not - but set it for low ohms such as 0-1000 if you have to.

The thermosensor should read 47-57 ohms at 176 degrees F and 14-18 ohms at 248 degrees F. If its off by more than 10% is should be replaced. They want the sensor to be immersed up to its threads and the temperature to be stable for 3 minutes or longer.

The fan switch should come on (~0 ohms) around 234-244 degrees F.
The fan switch should turn off (very high ohms) around 199-207 degrees F.

The thermostat should begin to open at 176-182 degrees F.
The thermostat should be fully open at 199-206 degrees F.

Thanks, i will post results tonight when i get off