OMC I/O THROTTLE ACCELERATION

[jjpizzle]

I have a 1988 Reinell Sporster 181 with a OMC I/O engine 190 HP. The drive is a cobra OMC. <br />My problem is when I accelerate with the throttle to no more than 3000 RPM's or roughly 20 mph it slows down to roughly 10 mph and then irregularly it will try to speed up( and you can feel it try) but then it will slow back down and continue to do this back and forth with out going no more than like I said 20 mph. I thought it might be the throttle cable slipping mechanically but I ran it and witnessed it throttle up and down by itself without the throttle cable moving changing it's position. I viewed this were the throttle meets the carberator. I also changed the fuel filter to see if that was it, no luck.<br /> If anyone can give me the slightest bit of help I would greatly appreciate it. I just bought this boat from a boat pro shop a couple months ago. So Im not so thrilled about what happened.<br />Thanks.

 

[Bondo]

Re: OMC I/O THROTTLE ACCELERATION

I can't tell you Exactly Where your issue lies,....<br />But,...<br />I'd say you've got a Fuel Delivery Issue,......<br /><br />Plugged Tank,.. Fuel Line,... Fuel Pump,... Or Possibly the Carb..........

 

[rbezdon]

Re: OMC I/O THROTTLE ACCELERATION

Search this siute for bogging issues. Many many responses to follow.

 

[jjpizzle]

Re: OMC I/O THROTTLE ACCELERATION

the boat is actually a 185 funrunner bowrider I/O.<br /><br />my mistake.

 

[stomper]

Re: OMC I/O THROTTLE ACCELERATION

I am also having problems in that area, when I take of the motor boggs down until I get on the plane, then it will pick up speed. In nuetral it will hit 6000 rpm, under load about 4000 until I get up then it'll get up to about 5000. by the way I have a 77 glastron 17 ft, 140 hp i/o omc drive, with the 4 banger chevy. I'm new to boats so a little info would help if anyone has some, I'd appreciate it

 

[rbezdon]

Re: OMC I/O THROTTLE ACCELERATION

Stomper, it sounds perfect to me. When you first take off there is a big "load" on the engine to get the boat to plane. This holds the rpm down because of the load. When the boat palnes there is less boat in the water and hence less load so rpm picks up. Most engines recommended Wide Open Throttle (WOT) rpms are just under 5000 so your getting every thing she's got. <br /><br />Josue has other problems because his rpm drops when the thrttle is opened, most likely fuel delivery issues.

 

[stomper]

Re: OMC I/O THROTTLE ACCELERATION

so do you think if I got a different prop it things would change

 

[stomper]

Re: OMC I/O THROTTLE ACCELERATION

it just doesn't get up and go like my buddy's boat he has a 17 crestliner 73 model with a 115 outboard just doesn't seem right

 

[rbezdon]

Re: OMC I/O THROTTLE ACCELERATION

To get a bit more hole shot you could go to a lower pitch prop but if you are really turning 5000 rpm now you are already a bit under propped. Going to lower pitch you would have to hold the rom doen by not running WOT once on plane but you would get there a bit quicker. I think you most likely have the best arrangement already it the info posted is accurate. It is not really acuratew to compare the two boats you are. There is a difference in boat length and most likely beam as well so you have much more hull area, likely quite a bit more weight as well. You are comparing apples and oranges, outboard to I/O, 17 ft to 18+, and who knows about the loads )people gear etc). All these factors make a big difference. I am not saying that I can tell every thing is prefect but the info you gave seems to indicate your getting every thing she's got, after all its a 4 smal cylinder, 4 stroke.

 

[whywhyzed]

Re: OMC I/O THROTTLE ACCELERATION

Originally posted by stomper:<br /> In nuetral it will hit 6000 rpm, ...... so a little info would help if anyone has some, I'd appreciate it

don't rev your engine over 5000 rpm... remember it's a 40 year old design of a pushrod engine...