shawn

I realize that no two engines will consume fuel at the same rate, but I have one that uses 20 -25 percent more than the other. One side will take 50 gallons and the other need 65 to fill up. I have swapped carbs with no effect. I have changed props with no effect, Both engines run like clocks, idle beautifully, start up turn key and run to 5600+ RPMs. My conclusion is that one needs to work harder than the other. What would cause this? My outdrives were rebuilt by Colobello and the props labbed finished. I checked the alignment before I put the boat in the water this year and its perfect. I have drive shafts and XRs. The drive shafts were lubbed in the spring. There is no discernible amount of fuel in the oil and the oil level does NOT increase.

Any ideas?

Thanks
Shawn

Poorsche

Is is possible tanks are slightly different size/capacity? Not much of a thought but possible.

Wobble

Is there any chance that the drives are not at the same trim angle when you are running? That could make for slightly different loads on the motors. Also have you verified the rpms on each motor by switching the tach leads at the dash or with a good timing light. etc.

shawn

Both engines are 502 rebuilt HP500s. I will check the drives, I measured them in the spring and marked the indicator panel, but anything is possible. I agree that its probably not the motor, but the load on it, I will swap the drive shafts to see if its binding up and creating a load condition. Its still got me baffled.

Shawn

East Coast B

Just a theory.... my boat has two switches which allows me to run off either fuel tank or both tanks at same time. If you have like switching capability, is it possible that the engines aren't using different amounts of fuel, but rather the valve system feeding the fuel is not regulating properly??? Again, just a theory if you have tank valve capability.... I'm not sure I can bite on that much extra fuel going into one engine, specially after you eliminated the carb as being a fault point... This is interesting.... keep us posted!!!! Good luck!

offthefront

Dont think that would matter .... as long as you fill them each time ......what you put in them would be what each motor used ...... How bout a slipping Coupler ?

Coolerman

Is it possible there is something wrong with your fuel senders/indicators? It could be possible that when your guage says it is full, it really is only 3/4 full or something like that. Just a thought.

GOODT

This May Sound Stupid But Taking A Shot .....
How About Throttle Adjustments Are You Watching Rpms While Running????? If Throttles Are At Diff Adj One Motor Is Doing More Work ....