Hi Guys,

Hope someone can help me out here. I have just installed a trail tech vapor computer on my HH250SS and am running into a couple of problems.

Firstly, now when I run the engine, the overheat buzzer goes off after a while. I installed the temp sensor in the coolant hose coming from the thermostat housing to get the most accurate reading of engine temp. Now, after the engine is running for a while, this hose doesn't even begin to get hot! Is it possible that I have an air lock of sorts somewhere within the cooling system preventing the water pump from pumping? I have 2 theories here...Either there is air in the system, or the thermostat is not opening (I have no idea why, it was working perfectly before the temp sensor install).
Also, what is the purpose of the small coolant line running from the radiator filler to the thermostat housing? (I have bypassed the carb fittings here as I have a 30mm pumper installed). Does it send hot water to the thermostat to get it to start opening? Maybe I have air or a blockage in this line?

Secondly, the RPM reading on the Vapor is very erratic and reading very high (like about 3500 -4000 rpm at idle). I have the tach wire connected directly to the coil terminal coming from the CDI, and the ground wire is connected to the main engine grounding bolt. The vapor is set to 1 pulse per revolution. I believe this is correct.
Would I be better off using the "wrap around the plug lead" method?

Any suggestions would be appreciated. Thanks.

I just put one on my wifes. sounds like you do have air in the system. let it run with the radiator cap off and it will burp itself.

I ran the tach wire around the plug wire 6 times. the manual says if the rpm is moving around alot to increase the number of wraps.

Thanks BIGE,

I'll give those ideas a try.

BTW, the exhaust kit I got from you when I was over there in the States is a Beaut! Sounds great and has given me a noticeable increase in power. The kids love the cool sound!

Howdy Beetle,had to go check mine to be sure. PPR =1,Pulse= 0000
My leads for tach are hooked directly into coil using stock females. Seems to work good for me. Good luck bubba.
Jon

BIGE,

You ideas worked. Tach and cooling system are all good now. However, I now I'm not getting any reading for engine temp. I checked the connections for the temp sensor and they seem all good. I had to extend the wiring harnesses for all the sensors. I used some twisted pair aircraft wiring (I'm an aircraft electrician) so , I'm pretty confident that all my connections are correct.

Anyone have any problems with their temp sensor reading on their vapor? Mine just gives me a big ---- degrees C.

I also have a pumper carb and had to by-pass that hose. No big deal.

Anyone have any suggestions as to why my vapor wont read water temp? Anyone had a similar problem?

Can I connect another water temp sensor to the vapor? I'm thinking of installing a sensor into the thermostat housing in place of the stock overtemp switch, and connecting that to the vapor wires. I wonder if that will work? Thoughts?

have you double checked the setting, the connecter? whats the minimum reading the vapor will read? my 250 took forever to get past 100 degrees

These 250s run relatively cool. It takes a lot to build a temperature. You have to work it pretty hard. It may just be you have not reached a minimum for the sensor to read.

Glade

Reset the Vapor and it should start reading,I had the same problem.There is a reset hole on the back of it Hope this Helps.