VintageVmax.com

After reading several times how the stock gauge doesn't seam to work well, I put on a Autometer Liquid filled temp gauge. It didn't want to do much either. Feeling the hoses, there was a big difference between the larger hoses and that small one that makes the loop for the temp sender. I will say this was mostly idling and reving it up on a stand, not out riding. Could the issue with all these gauges not working really be, not enough water flows through that small line rather then the gauges themselfs? I guess I'll find out if it ever snows here.

The gauge on the 540 does not even move under normal operating conditions (at least none of the ones I have seen) so, I have always felt the gauge need to be calibrated lower so, you could see a temp change. Reguardless, E.G.T. gauges are the best when checking jetting since, they react quickly.

I understand. I do have EGT, BTW I have one reg. probe and one fast responce open tip one, I really see a difference on the fast response probe.
I had a good water temp gauge just sitting around, I know it works, just suprized to see it not move much either. Maybe its lack of flow through that small hose, maybe it just needs high rpm to pump it. We'll find out if it snows here.

hmmmm you might have something there bob.... never really though of that.... but you would think after two hours of riding there would be enough hot water in that line to move the gauge.... i think the gauges were put on there by yamaha just to look important.... hell some of them dont even have numbers... what good is that?.... but you make a good point maybe it would be better to check the water temp somewhere else....


do you know what size of gauge you are using? i measured the hole yesterday because im looking to buy a new gauge.... the hole measures 2.25.... and it only has about 1/8" lip aroudn to hold the gauge in..... i can custom make something but i would like to get cose to the right size to begin with....

I used a 2 5/8 autometer just because I had it. Its bigger then the stocker which I guess is a 2 1/16 like most car gauges. I was going to mount it next to the MyChron but it looked too cluttered their so I put it on the side of the tank cover

i see... i was hoping to keep it in the stock hole.... guess im just gonna have to wing it hahaha

Statrt here buddy, hundreds of them, My guess is stock is 2 1/16 but havent measured
http://www.jegs.com/c/Gauges-Tachs_Gauge/10339/10002/-1

yeah im afraid 2 1/16 will be too small but if i find something thats too small at least ill have a room to find a ring to take up the gap.... i think im just going to buy one and find a way to make it work....

On both vmax's I have had I found that the tee where the water temp sensor screws into was pluged with crap so water could not flow.

yeah this is my next project while i wait on my EGT guages to come... im thinking of eliminating the hose all together and seeing if i can find a way to screw into the top of the head where the banjo bolt is now.... the stock sensor probably wont be long enough then but well see what i come up with when i can actually look at the sled....

yeah i got to looking at the the small line that the gauge taps into and i think your right bob... im off to the hardware store after work to try to find some fittings so i can tap into the big hose coming from the head..... if i can find the right sized T then this should be a simple mod... we'll see how it works

yeah hardware store #1 had no fittings to fit the gauge... back to the drawing board... stupid metric threads...

My standard car gauge fit the stock fitting. If I remember right from some past car projects, it isn't a metric, but it is something odd, I believe a pipe thread. I'm talking about the fitting around the probe

nah i dont think it is pipe thread... it will thread into a 3/8" fitting but it is all wobbly... with enough tape and/or some pipe dope i suppose it would seal up... but the bigger concern is the lip where the probe seals... its hard to explain and that why i made the new pictures only forum.... now if i just had a picture of it! hahahaha... ill get one at lunch....

Thats it, maybe itsnot called pipe, but it has to have that seal to the probe, maybe hydrolic, like AN line fittings