Gunson and mixture problems
 

I recenctly received a Gunson gastester from fellow pelican Jcon. I was originally going to just borrow it but he just gave it to me! That was beyond expectations and a testament to the type of people on this board.

Now, he was unable to find the directions for me but gave me a rundown on the basics. I fired the car up and warmed it up while the Gunson was warming up as well for about 15 mins. When the readout was steady, I tuned it to 2.0. So far so good.

Now, I was unable to "disconnect" the 02 sensor so I just cut the wire. Is this sufficient?

I inserted the probe into the exhaust and began to turn the adjustment screw. I didn't see hardly any movement on the readout on the Gunson. It just "hung" around 2.0. I was afraid to turn the screw too far. I only turned it beween 1/4 and 1/2 of a turn clockwise to richen it up. Was this enough? I did rev the engine before taking the reading.

Another question, could somebody post a picture of the back of their gunson so I can make sure the tubes are in their correct positions?


Thanks!

Is the CAT still on it?

Nope. SSI's and a 2in 1 out muffler

Make sure the probe is really in there. At least 8". Also go for a 20 min drive to warm it up.

The probe was in but it could have slid a little bit. The car was nice and warmed up......

I assume cutting the wire is the same as disconnecting it??

Also if anybody has directions they could email/PM me, that would be great!

Thanks!

Can you hear the diapharm pumping when you stick the probe in?

I let mine restabalize after each reading. I didn't try to take any readings "on the fly".

Yes I can. I guess the tubes are connected correctly then???


Shouldn't the reading move more than +- .1?? How much do I need to turn the screw?

So did I. But like I said, the readings didn't change hardly at all.

Hey Guys

I really need someone to break out their digital camera and take a picture of the back of thier Gunston. Brian needs to see if he hoses on the back are hooked up to the right ports. It sounds like thier not if he's not getting any change from 2.0.

I'm the one who sent him the tester, and I was not sure they were hooked up correctly ( which I let him know). I couldn't find any info or instructions on the Gunston website either. So what we need is a picture or a scan of the instruction manual.



As always thanks for the help.

Jeff C

Jeff,

I just found the instructions on their website. It was hooked up incorrectly. I fixed the hoses and now I am ready to try it out again tomorrow.

I looked for the instructions the other day and got errors when I tried to dload them.

Thanks again! I can't thank you enough

Great ...I don't know how I missed the instructions, but I'm glad you found 'em. Let us know how it turns out.

Enjoy!

Jeff C

Update..

I got it all to work and adjusted the CO to around 3.2 %. Also advanced the timing just a tad from the factory setting. Took her for a little spin and she runs like a top! Smooth idle and smooth acceleration.

When I tested it this morning, it was very rich, around 6% :eek: . That was from me screwing with it yesterday.

Thanks all!

Gastester photo....

Sounds like you have it whipped but here's a photo or two

Alhttp://forums.pelicanparts.com/uploa...1066020915.jpg http://forums.pelicanparts.com/uploa...1066020933.jpg

Thanks for the photo. That is how I reconnected everything so this just confirms my setup.

The only thing wrong with the picture, is you really should *****-can the cheapo plastic probe hose. It'll melt during a long test. It is w-a-a-y too short; that putting the unit too close to the tailpipe=poor and inconsistant readings. Use 10' of rubber fuel hose on the probe, and the unit will work much better.

As delivered, the Gunson is a bit of a toy. But with the above mod, and some patience, it's ok. A Sun 4-gas tester it is not!