Colortune??

[Cut2Short]

Anyone ever heard of a carburetor tuning tool called Colortune??

I’ve been really struggling on getting my 1988 Mercury 150hp XR4 to run the way it’s designed, while I’m still waiting for the carb kits to get delivered, I was talking to a friend who has a device called a Colortune. Supposedly, it has a glass sparkpug unit that you can see the different combustion colors (yellow being rich and bunsen burner blue being balanced, and white blue being lean) and fine tune the air/fuel mixture ratio by adjusting the various jets. I was hoping to find a little advice on how this tool worked and maybe the best way to use the tool. The literature says to do all of the testing at idle, but I was thinking of keeping it on the trailer, putting the motor in the water, placing it in gear and try running it through the various throttle positions. It comes with a little black tube with a mirror to enable you to see the clear sparkplug from a different angle than straight on, so I should be able to work off of the back deck of the boat.

Any shared experience would be greatly appreciated. Mostly, does it work.
Steve

[Mark75H]

I recall seeing ads for this device decades ago, but not recently.

[sschefer]

Are you still having problems? I'm taking mine up to 5000 ft on Sat. If I run into any problems I'll let you know. I just kicked the idle up to 1000 on the hose at sea level and then I'm going to run 87 in it. I haven't run this particular engine at that altitude so who knows.

[glassdave]

I recall seeing ads for this device decades ago, but not recently.

yep, i bought one years ago to tune the carbs on my old 1965 Triumph Spitfire. It worked OK and when i was sixteen it was very cool looking into a combustion chamber as it was firing. I'm not sure affective they actually are though. I still have it somewhere.

[sschefer]

I'm at 5000 ft right now. Before I left I kicked the intial timing up so I had 1000 rpm on idle at sea level. Idle is 750 at 5000 ft with in gear at 700. Without any jetting changes and dropping from a 19p to a 17p prop I'm seeing an expected hesitation out of the hole but not bad. Top RPM was 5000 but the engine did not feel terribly over worked. I'm running 91 octane fuel which is probably at contributor to the lack of power and hesitation. When the tank gets down later this week I'll refill with 87 octane and see what the difference is.

The boat still got up on plane quick and top speed, although down, was 41 on the GPS at 5000 RPM.

Hope that gives you some idea of what you should be expecting if you jet to sea level and the differences if you jet for your altitude.

[Cut2Short]

Thanks for the info Steve, as you can guess I'm still trying to figure it out. I'm waiting on ishopmarine to get the carb kits in, hopfully this week they'll get sent so I can get them in. Another guy I know is letting me use his Colortune, should be interesting to see what the flame looks like and make whatever adjustments I can. I was going to focus on the idle bleeder, if I need to change them at all once I rebuild the carbs.

Anyways, thanks again,
Steve