Posted By: jwcromer
wont run wideopen - 07/19/20 11:27 PM
mercury 150 year 2000 son took it out today,starts good,idle good, opens it up,runs good for 10 15 seconds then cuts back to half speed,will run all day like this but wont run wide open,whats my problem?
Posted By: grout-scout
Re: wont run wideopen - 07/20/20 03:35 AM
Clogged fuel filter?
Fuel lines deteriorated?
Posted By: gary purdy
Re: wont run wideopen - 07/20/20 12:53 PM
Going into Guardian mode? Does the warning horn beep when the key is turned to on?
Posted By: Fishin' Nut
Re: wont run wideopen - 07/20/20 01:09 PM
This was my solution. And I had the same symptoms as you stated.
Posted By: tmd11111
Re: wont run wideopen - 07/20/20 01:23 PM
Clogged fuel filter?
Fuel lines deteriorated?
^^^This^^^ 99% of the time
Posted By: Bradley McCaw
Re: wont run wideopen - 07/20/20 02:40 PM
Clogged fuel filter?
Fuel lines deteriorated?
+1 to this I had the same issue, looked at the fuel line and it was the cheap EPA hosing, new line instantly solved the issue
Posted By: jwcromer
Re: wont run wideopen - 07/25/20 06:24 PM
UPDATE: first thing I did was replace the fuel filter. I cut the old one open and found it was probably 75% clogged with sand. See pic. Checked fuel lines and those looked fine. Haven’t been able to get to the lake yet to test it but I’m pretty confident that was the problem. Next time out I’m also going to burn off all the fuel so I can check out the fuel tank and see if it has a lot more sand in it and clean it if it does. I’ll probably also replace the new fuel filter after I run the current tank of gas out to make sure there is no more sand.
Posted By: tmd11111
Re: wont run wideopen - 07/25/20 07:00 PM
Thats not sand. It the varnish that builds up over years of use with ethanol free fuel. Once ethanol fuel is introduced the varnish breaks up and clogs the fuel system. Was a big problem 15-20 years ago when E10 came out.
Posted By: jwcromer
Re: wont run wideopen - 07/25/20 09:14 PM
Varnish was my first thought also but after looking at it closer it is very uniformly granular like sand. Wouldn't varnish be more flaky? Or do the flakes of varnish get beat around and form a sandy texture?
Posted By: tmd11111
Re: wont run wideopen - 07/25/20 09:39 PM
Varnish was my first thought also but after looking at it closer it is very uniformly granular like sand. Wouldn't varnish be more flaky? Or do the flakes of varnish get beat around and form a sandy texture?
They slowly dissolve and look like large granular sand just like in your photo. Don't know what rig you have but if you can remove the fuel tank thats the easiest route to clean it. Another option is buy a couple of fuel filters and keep the tank full with E10 and change filters as needed. It will go away after a few tanks of fuel
Posted By: Flippin-Out
Re: wont run wideopen - 07/26/20 04:12 AM
You should invest in a more substantial aftermarket fuel filter with the large spin-on filters. I'd be frightened that crud would get past that small filter and trash the motor.
Posted By: SkeeterHawk
Re: wont run wideopen - 08/03/20 06:21 PM
It's called an inline water separator filter. Will clog up pretty fast with that stuff. But will catch it before it gets to the motor fuel filter.
Posted By: lurenthewind
Re: wont run wideopen - 08/05/20 09:49 PM
After you get it all cleaned up, you might want to consider using ethanol free fuel and StaBil 360 Marine fuel treatment. I use both of those and also Ring Free in my Yamaha outboard. So far so good and the Yamaha Fuel Systems suck.
Wayne
Posted By: SteezMacQueen
Re: wont run wideopen - 08/05/20 10:03 PM
After you get it all cleaned up, you might want to consider using ethanol free fuel and StaBil 360 Marine fuel treatment. I use both of those and also Ring Free in my Yamaha outboard. So far so good and the Yamaha Fuel Systems suck.
Wayne
The problem began by using ethanol free fuel. It’s varnish. But, you’re not gonna go wrong with either fuel as long as the fuel system is up to date. The problem is exacerbated by using e10 AFTER years of ethanol free fuel. The ethanol crystallizes the varnish and suspends it into the fuel allowing it to move into the fuel lines and filters.
Posted By: tmd11111
Re: wont run wideopen - 08/05/20 10:40 PM
After you get it all cleaned up, you might want to consider using ethanol free fuel and StaBil 360 Marine fuel treatment. I use both of those and also Ring Free in my Yamaha outboard. So far so good and the Yamaha Fuel Systems suck.
Wayne
The problem began by using ethanol free fuel. It’s varnish. But, you’re not gonna go wrong with either fuel as long as the fuel system is up to date. The problem is exacerbated by using e10 AFTER years of ethanol free fuel. The ethanol crystallizes the varnish and suspends it into the fuel allowing it to move into the fuel lines and filters.
Hummmm. Where have I heard that before
Posted By: SteezMacQueen
Re: wont run wideopen - 08/06/20 12:26 AM
After you get it all cleaned up, you might want to consider using ethanol free fuel and StaBil 360 Marine fuel treatment. I use both of those and also Ring Free in my Yamaha outboard. So far so good and the Yamaha Fuel Systems suck.
Wayne
The problem began by using ethanol free fuel. It’s varnish. But, you’re not gonna go wrong with either fuel as long as the fuel system is up to date. The problem is exacerbated by using e10 AFTER years of ethanol free fuel. The ethanol crystallizes the varnish and suspends it into the fuel allowing it to move into the fuel lines and filters.
Hummmm. Where have I heard that before
Reiterating. That’s all. It seems needed at times.
Posted By: tmd11111
Re: wont run wideopen - 08/06/20 12:34 AM
After you get it all cleaned up, you might want to consider using ethanol free fuel and StaBil 360 Marine fuel treatment. I use both of those and also Ring Free in my Yamaha outboard. So far so good and the Yamaha Fuel Systems suck.
Wayne
The problem began by using ethanol free fuel. It’s varnish. But, you’re not gonna go wrong with either fuel as long as the fuel system is up to date. The problem is exacerbated by using e10 AFTER years of ethanol free fuel. The ethanol crystallizes the varnish and suspends it into the fuel allowing it to move into the fuel lines and filters.
Hummmm. Where have I heard that before
Reiterating. That’s all. It seems needed at times.
It was more towards the slow learners