GT750Battleship wrote: Dave could please explain about the by pass valve..are you talking about the hole it the filler neck that allows coolant to flow to the reservoir bottle under the tank
Cheers,
Roger
This page out of the manual tells about the thermostat function http://www.oldjapanesebikes.com/mraxl_G ... /sr57.html" onclick="window.open(this.href);return false; the bypass part is open when the engine is cold and thermostat is closed
allowing coolant to flow through the engine and then right back to the pump without going through the radiator to allow quick warm ups . But then as the water warms enough the top part of the thermostat starts to open allowing coolant to reach the radiator . At the same time the bypass portion of the thermo closes off ( the small hose going from the head down to the starter area ) .. if this doesnt happen with the engine at speed the coolant bypassing the radiator could cause a over heat . Pinching the bypass hose with some long nose vice grips ( mole grips for you guys across the big pond ) is a easy test to see if the bypass is allowing the overheat .
Sorry Dave...having a seniors moment !! & recovering from a bad chest infection !!
Realise now you were talking about the thermo !!
Doh....please pass the beer & donuts !
Cheers,
Roger.
jeff kushner wrote:I know that you've said the gauge is reading a bit higher than it used to...does it "FEEL" hotter? If you've owned it for while and ride it often, you know your bike....does it really seem that something is wrong or is it just the gauge? Lastly...a gauge is 20 bucks...maybe swap it to see?
The bike does feel all around warmer to the touch.
I did test my gauge and sender with a pot of boiling water on the bike and it shows 185 in the middle which is accurate
Suzsmokeyallan wrote:Did you try using an infrared hand held thermometer on the components to verify surface temperatures when running?
I have one but the readings were all over the place and unreliable.. I just bought a nice one today and will be testing it shortly.
Suzukidave wrote:Pinching the bypass hose with some long nose vice grips ( mole grips for you guys across the big pond ) is a easy test to see if the bypass is allowing the overheat .
Sorry to hear about your temp problems. I remember always hearing about other Buffalos always running cool, while mine would run up when running at freeway speeds. I too went through a lot of investigation and never found anything wrong. I live in Tucson and have ridden in 110 with two up for hours on end at highway speed (75, 80 actual mph). It will get up there, but never overheats.
Does anyone knows if the sending unit increases resistance with temperature? Maybe the sending unit is in error.
I agree with Holy....that we are used to hearing that the cooling system works almost too well but a big clue is that he recognizes that his bike IS running noticeably hotter. I can't view his video here at work (You tube blocked) so maybe there is some bit of information that one of the guys will see. That it's taking 20 minutes to warm up might also mean something. I've got a vested interest in finding the cause of your issue because I'm getting ready to produce a lot more heat than a stock engine and I've elected to remove the stock radiator for a lightweight re-purposed heat exchanger and I've sized it based on the heat shedding ability of the stock. So if there's a gremlin in the works, I want to at least be aware of it going forward.
When you removed the water pump cover, did you check to see that it would only spin with the engine and couldn't turn on it's own which might reveal a damaged or partially damaged shaft or impeller pin? I'm sure that with your skills to dis/reassemble, you checked everything as I would have but it can't hurt to ask.
According to everything that I've read in this thread.....if you remove the t-stat altogether, you still have the over or near overheating? Or does the situation change?
Well shoot this is getting pretty hard to figure out I suppose you have checked the timing marks with a dial gauge ? It sure looks like you have ruled out the cooling system so that leads to mixture , electrics or timing . On your next ride test put a couple of pieces of masking tape on the throttle .. one on the grip and one on the switch . mark the piece on the grip for closed throttle , 1/4 , 1/2 and full throttle so we can tell where the throttle is at the engine over heating .
Last edited by Suzukidave on Wed May 28, 2014 9:37 am, edited 1 time in total.
From looking at all you have checked and done so far I'm thinking the problem may be either the charging circuit, gauge or sensor.
It does not take much input voltage to move the gauge from normal to where yours is. Run a voltage check on the orange wire at the regulator socket with the ignition on to see what value is reaching there.
Dave could please explain about the by pass valve..are you talking about the hole it the filler neck that allows coolant to flow to the reservoir bottle under the tank
) is a easy test to see if the bypass is allowing the overheat .
Sorry Dave...having a seniors moment !! & recovering from a bad chest infection !!
