Fuel Usage - 1986 Force 125 on 18' bayliner bass boat

[mbhoag]

OK, This summer I purchased an 86 Bayliner Bass boat with an 86 Force 125. Filled up the gas tank (I am guessing 20 gallon) with fresh gas and have now had it out on the water 3 times. I have only been on a small no-wake lake and had engine running a total of 4-5 hours at pretty much idle speed. I did clean carbs and install a new stator and two power packs. (FYI, Engine seems to run great with no known issues)

Here is my question. My gas gauge shows I have only used about 1/4 tank of gas. It just seems like I should have used a lot more than that, so I wanted to get an idea as to how quickly it should go through gas. I am planning on taking boat out to a lake this weekend that I can finally do something faster than idle. I would love to know how it runs at actual speed!

I have noticed that the gas guage only drops to 1/2 tank when key is off (even after Perko switch is turned off) so I wonder if my gas gauge is incorrect. I am thinking I might top it off at gas station before I hit the lake... would hate to get 5 miles from the ramp to learn I am out of gas.

Is there a good way to test the gas gauge?

How much gas should it use at idle (no wake) speed vs wind-through-my-hair speed?

 

[jerryjerry05]

Re: Fuel Usage - 1986 Force 125 on 18' bayliner bass boat

The way to test the guage is unhook it.Then see if it drops all the way to E.
Re hook it and ground it out.It should go all the way to the top.
This boat's been around and who knows if the sender is original or someone has replaced it and put it in wrong.
If all you've done is idle it can last a long time.
I'd take along a can or two of gas.
I carry 2-3 8oz bottles of oil.Then when I'm not sure I put in 3 gal at a time.J

 

[pnwboat]

Re: Fuel Usage - 1986 Force 125 on 18' bayliner bass boat

I had the same issue when I first got my boat. When I took a closer look at my built in tank, it had a stamped plate with the capacity (20 gals). I noticed that it was only about 9 inches tall. Very shallow so it really makes it difficult to get an accurate reading unless you are stopped and the hull is perfectly level. I'm guessing the tank is probably about 20 inches wide, not sure how long. The sending unit is at the very back of the tank towards the stern. I've adjusted the float arm on the sending unit but it really didn't make much difference. I tested the sending unit by moving the arm to full, half full, empty looked at the fuel gauge and it was fine. I've learned that if I'm under way at full or close to full throttle, and my gas gauge is reading 1/2 a tank, I better start looking for some gas. When the gauge reads 1/4 tank under the same conditions it's about half empty. I've confirmed this when I fill it up at the pumps. I always keep some 2 stroke oil in the boat at all times.

 

[mbhoag]

Re: Fuel Usage - 1986 Force 125 on 18' bayliner bass boat

Here is an FYI follow up... Took boat out today, but stopped at gas station and filled up. Took 6 gallons (needle showed little less than 3/4 tank full before fill up) so it appears gauge is accurate even though with no power needle sits at about 1/2 tank.

I do question whether it would give a good reading below 1/2 tank, so I may get a new one this winter along with some other gauges I am getting, just to be safe.

 

[mbhoag]

Re: Fuel Usage - 1986 Force 125 on 18' bayliner bass boat

Follow up - Tested sending unit and it appears to be fine, gauge on the other hand is very optimistic and always reads above 1/2 tank. Picked up a new gauge today and dropped it in and I now have accurate readings!. I'm actually glad it was just the gauge and not the sending unit, 10 minutes to replace and I am done!