AQ125A sooty residue

[Blackpony]

We have an '85 AQ125A in a Capri Bowrider that by any standards has been a low-use boat since we purchased new. In fact, it was in storage for near 5 years until we started using again this season. The engine has never smoked and uses no oil between changes, however even when new we would have a sooty residue left on the outdrive and transom area at the water line after each outing. After a recent week-long houseboat vacation with the boat in use everyday, the sooty residue was much more prevelent. Based on others' experience, I assume this means the carb is set too rich. However, I also noticed the same sooty black in the engine oil after a week of skiing and tubing (about 20 hours of running). The engine ran great except for a short time after running at low idle while fishing. Is the black in the oil also the result of too much fuel in the carb setting or is it indicative of something more serious?

 

[rbh]

Re: AQ125A sooty residue

was the old fuel removed before you put it back in service?
was the boat hard to start as well as sluggish on throttle up?
five years is a long time to sit.
rob

 

[jtybt]

Re: AQ125A sooty residue

Probably wrong jets. Could have to do with your altitude. Black in the oil could be from boat being 25 years old sitting so long. The rings may have been partially frozen to the cylinder walls and scoured them badly when you started up again.

Change oil often at first and see if those symptoms go away.

I'm re-setting jets in my carb now from too lean which is more dangerous than too rich. It's not a particularly difficult process. Generally, the bigger the number the richer the jet. Don't go more than 2 sizes smaller at a time. If she's running OK otherwise, re-jet and keep an eye on things

 

[Blackpony]

Re: AQ125A sooty residue

The old gas was removed from the tank and replaced with high-octane fuel by my local marine service who started the engine for the first time since the lengthy layup. He said it took him quite a while to get it running smoothly and admitted not being too familiar with the carb on the AQ125A. The most recent use of the boat (a week of skiing, tubing, etc.) was at a bit higher altitude (2000') rather than sealevel (freshwater lake) where we used it right after reintruducing it to water. Yes, the boat was a bit sluggish on throttle-up and I did have to adjust the idle up to spec (900 rpm) at the higher altitude. I'll change the oil an see what the new few hoursof use bring. Many thanks for your perspectives and advice!

 

[PiratePast40]

Re: AQ125A sooty residue

I have an AQ130 that sat for several years and it also left a somewhat sooty ring the first several outings. It seemed to clear up after about 20 hours of operation which included both low sped fishing and WOT operation. The carbs on the 130 are the same Solex carb as on the 125. Although we live near sea level, we typically boat at around 1500 feet. This past weekend, I took the boat up to several lakes at around 4400 feet and then up to East Lake at6500 feet. Even though it was running richer at the higher elevations, the oily bathtub ring at the outdrive has gone away which indicates that the rings have set back in.

Yes - you definately need to reset the idle for the higher elevations. It wouldn't hurt to play with the mixture as well. Make sure you also let it warm up and set it again so you can keep the idle below 1000 rpm to avoid the "clunk" when putting it in gear. At the higher elevations and cooler than normal temps, you won't be the only one with a reluctant engine. The guy with the can of starter fluid soon becomes everyones friend!

After that long a time in storage, it's not unusual for seals and gaskets to dry out or varnish to gum up the carb. A carb rebuild on the Solex isn't that difficult and probably a good idea.

Let us know how it comes out.