Amount of Gas Engine Should Use?

[papakevin]

I actually have two beginner questions if you don't mind. <br /><br />I have a 1988 Evinrude 48 SPL on a 16' fiberglass boat. If I'm running the boat WOT for about an hour, how much gas will I use? Is there a rule of thumb, etc?<br /><br />Second question - I don't have a tach on the engine. Is it wrong to run the engine at full throttle for an extended period of time? In order to get the boat on plane, I have to run the motor full out. At the lake I go to, there's a lot of boats, traffic, so I need to keep it running near or at WOT to keep moving. Plus it's more fun...<br /><br />The engine doesn't seem to be overheating, but I don't want to press my luck. Will running the engine hard hurt it, or do these motors like to run. Help!

 

[KCLOST]

Re: Amount of Gas Engine Should Use?

hp/10 = Gas usage per hour at WOT...<br /><br />No problem running at WOT.. Just do your maintenance on the regular items to make sure it is cooled properly.<br /><br />Should not hurt it.. But it is worse case for the motor...

 

[roscoe]

Re: Amount of Gas Engine Should Use?

Max gallons per hour will be about 4.<br />You can cut it to 3 gallons/hr by cutting engine speed 20%.<br />I know, hard to do without a tach.<br /><br />Engine will run at wot for a long long time if it is getting proper water flow to cool it AND you are not lugging or over revving the motor. I know, hard to do without a tach.<br /><br />So how do you know? <br />Buy a tach.<br />Mount motor at correct height.<br />Prop motor to run in the 5500-6000 rpm range.

 

[papakevin]

Re: Amount of Gas Engine Should Use?

Anyone know where's the best place to get a standard tach for my 48 SPL? I believe there is a tach connection (two lead) on the OMC controller. Do I need a boat tach or will an auto tach from Walmart work?

 

[Moody Blue]

Re: Amount of Gas Engine Should Use?

Sorry, the auto tach is not compatible with outboards. Need to find a marine tach for outboards with a 7000 rpm range. Keep an eye out on e-bay. Got my brand new Faria for $26.00. Better than paying $170 from the dealer.