2002 60HP Bigfoot 2 stroke - Idle issues

newcomlr

Petty Officer 2nd Class
Joined
Jul 5, 2012
Messages
125
Recently acquired a toon with a 2002 60HP Bigfoot 2 stroke. When I was checking out the boat from the previous owner, he started the motor easily...just reached in from the dock, turned key...no problem.

I don't know how long his gas had been in, so I topped off the tank (about 5 gals) when bringing it home. Started fine the first few times, although I had to give it some throttle to start. I added some Seafoam to the tank.

Now I can't keep the motor running after starting. Start it up...have to keep goosing the throttle while in neutral and when i back off toward idle it wants to die. Or if it's warmed up a bit, I can start it in idle, but if I apply throttle in neutral it will die. When I get it out in open water it runs fine, although may be a little down on power. But when I pulling back to the dock, it dies at low rpm. Then it is hard to re-fire.

Replaced the primer bulb as it was clearly detoriating and wouldn't get hard. New one seems to work. Added a clear inline filter so I can see gas. Removed fuel lines and insured no blockages all the way to the strainer in the tank. No real changes to the problems.

Going to change the inline fuel filter under the cowl today (probably leave the clear filter housing I added but remove the filter). Will change engine fuel line quick connector. Will also drain the fuel tank and attempt to clean. Will check and change plugs in case they've become fouled.

If none of the above solves the issues, I assume next step is to have the carbs looked at. Any other thoughts? Just not sure why a motor that seemed to start and idle so easily now has these issues. The only change I made that preceded the issues was adding seafoam.

Maybe unrelated...but sometimes when I start, the tach shows crazy readings...like 2X actual RPMS
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,778
Re: 2002 60HP Bigfoot 2 stroke - Idle issues

From the bad bulb comment you probably have clogged your under the cowl fuel filter. I'd take the inlet hose that you remove to replace it and point it into a suitable container and using the prime bulb, squeeze it and pay attention to what comes out of the hose. Also you can blow through the filter (with your mouth) in the direction of the arrow....same direction as fuel flows, and see if you can easily blow through it. If not, you found your smoking gun. Just clean out your fuel line till you only put clear fuel into the container.

Then, give your Sea Foam time to work and I hope you put in a significant amount of it to do some good.....till you get things cleaned up. Then, if you still have problems do a carb kit and clean out your carbs.....I use Berryman's Chem Tool aerosol. It is great for dissolving varnish and cleaning carb ports. I have used other things/brands over the years and this is the best I have found. It will dissolve paint so watch where you spray it.........but that's what it's made to do.....dissolve varnish.

I just put a new fuel line and bulb on my engine (10 year old) with a new engine filter because the line and everything else was full of brown crud. I replaced with a clear line and doing as I mentioned cleared the debris out of the line. I have no more crud in my line with the new hose.

HTH,
Mark
 

newcomlr

Petty Officer 2nd Class
Joined
Jul 5, 2012
Messages
125
Re: 2002 60HP Bigfoot 2 stroke - Idle issues

So I spent quite a bit a time working on the motor while boat is docked. Already had some Quicksilver cleaner so sprayed that in the carbs and that certainly made a difference. Changed the internal inline filter..it definitely had some gunk in it. Changed plugs too though the old ones weren't too bad.

On this motor, you have to remove the oil injection tank to get to the fuel filter. When I started to pull out the oil tank, I noticed the zip tie that holds the hose on had slipped off the end of the hose and as i started to lift the oil tank (still full at the time), the hose slipped right off. Glad I caught that! Why do they use these zip ties on such critical connections?!?!? I reattached with two new zip ties, but will definitely be replacing with a stainless clamp!

Engine runs better now, but still won't always idle smoothly and will occasionally stall. To dock, I have to make a sharp turn into the slip space and it's an adventure everytime. Going to increase the ratio of Seafoam and respray the carbs with the Berrymans you recommend. If that doesn't fix the problem will have a mechanic look at it. I think the Boat runs good at speed but since I've only had the boat for a short time, I don't know what "good" feels like. Once I get this all straightened out, I suspect I'll get more power/speed at less RPMs.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,778
Re: 2002 60HP Bigfoot 2 stroke - Idle issues

I have a 12 year old engine and my ties are still in good shape. I'd go back with the tie personally. I think they do a better job of sealing a smaller diameter hose/barb interface. Give your engine some time to clean up. Keep doing what you are doing. When you sprayed you proved a point that the engine is running lean. Agree that once you get proper fuel to the engine it will perform better, but the prop/trim position sets the rpms. All the fuel does is determines just how many you are going to get at WOT, and expect more, not less.

Mark
 

newcomlr

Petty Officer 2nd Class
Joined
Jul 5, 2012
Messages
125
Re: 2002 60HP Bigfoot 2 stroke - Idle issues

UPDATE: My motor/idle issues were occurring with my first tank of gas. When I bought the boat (has a 20 gal tank), it had about 2/3 of a tank full. On the way home I topped it off.

I ran it down to about a 1/4 or less with lots of Seafoam, then added a fresh six gallons a few days ago. Viola! Starts quickly and idles fine now.

One question...should the fuel cap vent valve be closed when not running the motor to help keep water out of the fuel? I bought a water separating filter but haven't installed it yet since I didn't want to introduce a new variable while I was sorting out the idle issues. But will be installing the new filter this weekend.
 
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