force 125 worst fuel mpg ever/fuel pump?

[danny9696]

Hi all I have an 89 force 125 that I was fighting a low rpm issue and had some great help on another thread but along with low rpm and all the work to resolve it I was out in the boat today and it started bogging down very bad almost like a miss and I used a 1/4 tank of fuel in about thirty min or less, I just rejetted it for high elevation and should have done better on fuel but not the case. could this be caused by a bad fuel pump?

 

[john from md]

Re: force 125 worst fuel mpg ever/fuel pump?

As I said in the other post. I would check your wire connections from the trigger to the CDI units to the coils. It sounds like your ignition sequence is not correct. This will act as if you have a dead cylinder.

Also, your engine needs a good decarb as your compression numbers are low.

John

 

[danny9696]

Re: force 125 worst fuel mpg ever/fuel pump?

John thank you for your info I will get the wiring checked today, but this prpblem started out of no place, and I think my compression numbers are low due to a low battery when i did my test, how is the best way to do a decarb on this engine

 

[john from md]

Re: force 125 worst fuel mpg ever/fuel pump?

Go to the FAQ section under the repair and maintenance heading of this forum. Scan it to find how to do a decarb of your engine. It is very easy to do.

A slow starter motor will give lower numbers on the compression check.

John

 

[danny9696]

Re: force 125 worst fuel mpg ever/fuel pump?

Thank you john I will check it right now, it was strange it ran great the first two times I was out with it but the fuel mileage gets worse every time I take her out, it is smooth though not like a miss it just happened that fast, I did however check the spark today and it was good on all four, now it won?t even idle without being started at wide open throttle, and to use five gal of gas in less than thirty min really threw me for a loop. power was there and then gone then it was back then gone then it stayed gone, I even tried to adjust the carbs and it did not affect it when I had both idle mixture screws all the way in that?s why I thought maybe fuel pump had a hole in it and was sucking fuel straight into the engine

 

[john from md]

Re: force 125 worst fuel mpg ever/fuel pump?

When the engine is running, can you get it up to speed? If so, how fast does it go and what is the rpm?

John

 

[danny9696]

Re: force 125 worst fuel mpg ever/fuel pump?

Hi John before the sudden power loss I could get it up to 38mph wot @ 4300 max rpm, the rpm seems low but it sounds right I need to put a clip on tach on her and see if my tach is right. I have only had this boat for about five weeks, but I got it from phoenix Az and it was at 2500' I live in the mountains and run it at 5000'-6000' hence the rejetting. Now with the power loss I can not even get it to idle but the engine is smooth.

Thank you for all your time and help john

Danny

 

[john from md]

Re: force 125 worst fuel mpg ever/fuel pump?

That engine should run at 5000 to 5500 RPM. Check to see if you have any slop in your carb flange nuts. Also check the vacuum lines on the side of the engine and beneath the intake. The failure to idle may be from a massive vacuum leak. This would allow the engine to run poorly at higher rpms but not run at all at lower rpm.

John

 

[danny9696]

Re: force 125 worst fuel mpg ever/fuel pump?

John I just got to thinking about the sudden loss of power I had with my boat, I have been going through it with a fine toothed comb and can?t find anything wrong, I was just about to pull out the last hair on my head and had a thought, the boat ran great right off the trailer for about five to ten min then is lost all power, I did just fill up with fuel on my way to the lake and had put about ten gal in it at the lake the last time I had her out and had not ran it since, could I have gotten some bad fuel that could have caused this sudden power loss and the lack of idle? I guess I should put a water separator on it!

Any way it is just a thought let me know what you think

Danny

 

[john from md]

Re: force 125 worst fuel mpg ever/fuel pump?

Your theory is easy to prove. Buy a three gallon tank from Bass Pro, West Marine, Cabelas etc. and hook it up. If it runs, you know your problem is with the existing fuel supply or supply lines.

John

 

[danny9696]

Re: force 125 worst fuel mpg ever/fuel pump?

Well I finaly figured it out, it was a leak in the fuel pump, I also did a decarb she runs great but I still cant get the rpm I need, I even put a 15 pitch prop on instead of the 17.

Thank you for all your advice

Danny

 

[danny9696]

Re: force 125 worst fuel mpg ever/fuel pump?

Hi all I finaly found the problem I was having, I had a short in a wire going to the #4 coil. Boat runs great now and fuel mph is much better.

Thank you all for your help

Danny