I have a 1990 50 hp force motor .The thing is burning alot of fuel and dont think its the carb.any help?

Question

dont tnink its the carb but could be thats not realy my area?any ideas?

Answer 1

change or repair the prop and dont run it w o t  make sure the bottom of the boat is clean too

Answer 2

my 50hp outboards burn a lot too. they get like 4 mpg or something

Answer 3

I don't think it's the carb either---carbs don't burn fuel.

Are you saying it's burning a lot more fuel now than it did before?  More than 5 or 6 gallons per hour at full throttle?

What other symptoms?  Cold start, warm start, idle, acceleration all ok?

If your fuel burn rate has increased with no noticeable change in performance, I suspect you're leaking fuel into the lake.  Get somebody to squeeze the primer bulb while you inspect all the hoses and fittings under the cowl.

Answer 4

If you have checked for fuel leaks and your lower unit oil. Check for excess weight in boat. Could be water trapped in bilge or gear stuffed into all hatches.Boat prop can also affect fuel economy. Good luck.

Answer 5

A rule of thumb on fuel consumption for outboards is for every 10 hp you use 1 gal per hr wide open so if you have a 50 hp. outboard  you will burn about 5 gal per hr. If you bring your boat to a plane and just back down a little on the gas and don't run at full speed your gas consumption will be lower.I have over 50 years in boating mostly outboards as well as 20 years in a boat yard working on everything from outboards to diesel engines,  

Answer 6

What makes you say that? That is the most logical answer, but you could have a hole in the fuel pump diaphram. The gas could be bad and it has been adjusted to burn it anyway. The lower unit could be going out and causing a lot of drag on the power head so you putt around all day at 20mph and the engine has to run like sixty. Timing could be a factor-Does it bog down on acceleration or try to backfire? By the way if it successfuly backfires, the reed valves are shot.

Answer 7

Take a close look at the prop.  One blade bent just slightly will cause the increase of fuel consuption that you are experiencing. You might not notice the change in proformance.  Otherwise check all the stuff that Jtexas said.