Thinking of switching

[DJ_Callahan_27]

As some of you may knowI own a 1988 19' Laser 3880 bass boat. It now has a Johnson GT 150 on it. The boat will flat out fly. Not sure of how fast that it will go (no gps as of now). On the lowrance x85 that I currently have on the boat it reads in the 90's. I know that the speed wheel type speedo's on this unit isn't accurate and not claiming that to be the true speed of the boat but the dash mounted speedo (also not at all accurate) quits at 65.

Anyway speed isn't the issue. Fuel consumption is. I'm wongering how small of a motor I could put on this boat and still get on plane easily and have a respectable topend speed alone with better fuel economy. Or would I be better off going with a newer motor of the same HP?

DJ
http://i629.photobucket.com/albums/u...9_09060056.jpg

[zx150]

I have a 250 Yamy and I just get it on plane and keep it there and don't go all out and it is much easer on the fuel than if I run 3/4 speed. Have you tried to change your plugs?

[DJ_Callahan_27]

The motor is running great. I have changed the plugs and wires. I think it has more to do with the fact that it is an 1984 model than anything else. I was thinking of going with a newer E-tec ( not new can't afford a new one). The newer motors are claiming to get 5+ MPG. I have found some of the E-tecs in the 99'-02' model that aren't to steeply priced if it would really impove fuel economy.

By the way my boat will not only plane off but will run farly fast at about half throttle but still won't get nowhere close to 5 MPG.

DJ

[zx150]

What would a new motor cost? I bet you could buy a hole bunch of gas for the price of the new motor. Just my .02. I think I would figure out something else out. But, that is just me. I hear those e-tec's are sweet, just be sure it is not the first year they made them I heard they had a bit of a problem with them. You also have to be an E-tec certified mechanic to work on them or you can have big problems.

[billm_usa1]

I'd look at a new set of performance reeds. The ones you have are probably worn out after all these years. Boyson has a set of performance reeds that are 2 stage vs the single stage you've been running. Due to the better reed design they claim up to a 10% increase in fuel economy. Check E-Bay they run about $150

http://cgi.ebay.com/ebaymotors/JOHNS...ssoriesQ5fGear

[DJ_Callahan_27]

Will the reeds really give it a 10% increase in fuel economy you think? I can't see it helping to much. The motor as is will start and idle without having to touch the warm up lever. Idles smooth and isn't lacking at all in accelaration. All the things the new reeds promises to improve to acomplish the 10% increase in fuel economy.

DJ

[billm_usa1]

Consider that the reeds in your production motor are over 20 years old and they bend every time the cylinder takes a breath they can get very tired and not have the same spring they did when new. The reeds are the heart and soul of every 2 cycle outboard motor. Better reeds will certainly help.

Another Item to look at is switching from a 4 blade prop to a 3 blade (less drag)

When was the last time your propellor was refurbished, blades sharpened, and surface polished ? costs about $150

What about adding a nose cone to your motor. Again ruducing drag
http://www.bobsmachine.com/products/...ne_Bigfoot.cfm
~$150 if you do it

Waxing/cleaning/repairing scratches on the bottom running surface of the boat is also something that will help.

Every one of these things will help and are cheaper than a new motor.

[hardestyeric]

I had a 1988 Johnson 200 and as long as I kept it below 5000 rpms it didn't use that much gas. Keep your foot out of it, take extra weight (tackle) out, make sure your set-up is right on, and make sure your prop isn't all dinged and bent.
Eric H.