15mph then nothing?

[BUMP]

Hey fellas, I've just recently aquired a 89 omc cobra (Sunbird or Corssica 175) 2.3L. The guy who gave it to me ran oil in the gas, assuming it needed it He couldnt get it started, so i traded it for a programmer for his truck. Anyhow, i drain fuel, replaced a plugs and a few hoses, it starts and runs.
The real problem: took it to the lake today for the first time, soon as i got to open waters, start to speed up, right at around 15 mph it "shuts down" (not the engine) or " slips outof drive"and i have to bring the throttle back to neutral then throttle up again. It acts like it wants to stall if i don't go back to neutral. Best way i can describe it, is like driving a standard 15 mph in 1st and pushing the clutch to the floor. Im also having the " shift cable problems" ive been reading alot about, could this be related? your fountian of priceless knowledge is much appreciated.

 

[rodbolt]

Re: 15mph then nothing?

redo your post.
it either revs up while the hull slows or the engine tries to stall. we cant figgue out which your describing as you describe both occuring at the same time .

 

[BUMP]

Re: 15mph then nothing?

I apologize, when at around 15 mph, i try and speed up, it feels as if it slips out of gear or something, but it goes right back to idle, then i pull throttle back to neutral immediatly then back into gear and accelerate normally then happens again. tried to accelerate fast and slow both with same results.. The engine does "stumble" but to be honest, i didn't give it time to stall. I'm sorry, i knew i would have a hard time describing it. It cuts out so abruptly it dang near throw me out of the boat. Thanks for you response.

 

[Coors]

Re: 15mph then nothing?

http://forums.iboats.com/showthread.php?t=167561
and check the anti-siphon valve.

 

[BUMP]

Re: 15mph then nothing?

Exellent, I will check allllll that out as soon as its not raining, thank you sir, i know th carb needs a workin on, but i leave that to a pro, Its hard to put the engine on a load as the lake is not a ready option usually. there for, I will eliminate as many of the discribed possibilities as i can. I did replace a hose from the carb to the fuel pump that was completly clogged, and replaced fuel filter. thanks again. i hope thats all it is.

 

[Coors]

Re: 15mph then nothing?

Exellent, I will check allllll that out as soon as its not raining, thank you sir, i know th carb needs a workin on, but i leave that to a pro, Its hard to put the engine on a load as the lake is not a ready option usually. there for, I will eliminate as many of the discribed possibilities as i can. I did replace a hose from the carb to the fuel pump that was completly clogged, and replaced fuel filter. thanks again. i hope thats all it is.

You probably have crap in the tank, all the way through every thing, including the carb.

 

[BUMP]

Re: 15mph then nothing?

I wouldn't doubt that at all! The previous owner ran oil in the gas 1st, plus been sitting for 2 years. I thought i got all the old gas out. Replaced the fuel filter. I'm thinking now on top of what i read, to have the card re-built and tune all nice and re doing the throttle cables, hopefully that will get r done. I was quoted 450 to rebuild the carb by a local place near me.

Is it Ok to put the boat in gear out of water? (with the ears on of course)
Sorry, first boat.

 

[Coors]

Re: 15mph then nothing?

Yeah, on muffs- not over 2500 rpm or so.
That tank needs serious cleaning- have access to pull it?

 

[Coors]

Re: 15mph then nothing?

You can buy a new marine carb for a lot less than $450.

 

[BUMP]

Re: 15mph then nothing?

all right then.. and !! new carb for less?? no kiddin', i assumed it had to be that exact brand in which it was designed for that engine.I guess if you can doit on a car, why not a boat. Is there a particular brand or place you would recommend i look into? The tank is built in as far as i know.

 

[BUMP]

Re: 15mph then nothing?

just a thought, if the tank may be an issue by not being able to remove or replace it and what not. can i not get the fuel system squared away, i.3 new card, fuel lines and filter, and install some kind of "pre-filter" inline close to the tank? easier for cleaning on the water if need type deal?

I found this, that would be MUCHO better than 450 re build ( if its the same one)

120-/2.5L

1983

1989

M2/MERCARB

L4

Y38-4

$228.00

$88.00

Click to
Order

 

[HT32BSX115]

Re: 15mph then nothing?

You could just go to Flying Fish http://www.flyingfishcarburetors.com/

They'll have what you need. You can either have them rebuild yours or they'll exchange it for a rebuilt one for somewhat less than $450...

 

[tigerhack]

Re: 15mph then nothing?

Hey fellas, I've just recently aquired a 89 omc cobra (Sunbird or Corssica 175) 2.3L. The guy who gave it to me ran oil in the gas, assuming it needed it He couldnt get it started, so i traded it for a programmer for his truck. Anyhow, i drain fuel, replaced a plugs and a few hoses, it starts and runs.
The real problem: took it to the lake today for the first time, soon as i got to open waters, start to speed up, right at around 15 mph it "shuts down" (not the engine) or " slips outof drive"and i have to bring the throttle back to neutral then throttle up again. It acts like it wants to stall if i don't go back to neutral. Best way i can describe it, is like driving a standard 15 mph in 1st and pushing the clutch to the floor. Im also having the " shift cable problems" ive been reading alot about, could this be related? your fountian of priceless knowledge is much appreciated.

Change your anti-siphon valve first i was having the same problem i did everything and replacing the anti-siphon valve solve the problem ,i am not saying your carberator might not be bad also, but change the anti-siphon valve first .

 

[QC]

Re: 15mph then nothing?

I am strill a little confused on the symptoms. You said that it feels "like driving a standard 15 mph in 1st and pushing the clutch to the floor". Does it rev up at that point? Or try to stall? Sounds like the latter, but I am concerned that we are jumping at a diagnosis without clearing up some basic stuff. More than once you said something about slipping out of gear. The fact that this is happening at the same speed is making wonder about a prop hub or something in the driveline . . . Just needs to be eliminated from the discussion.

Also, I would not change your anti-syphon valve or the carb until you run it from a clean source of fuel. Rig up a small, clean supply independent of the boat's fuel system, bypassing the filter too . . .

 

[BUMP]

Re: 15mph then nothing?

Thanks guys for your advice. I'm not exactly sure were this anti siphon hose is, but i'll look it up. And, when i say "slips out of gear" thats just what it feels like. The guy that owned it before me had the same problem as i did, just at a higher speed. he was getting to 35-40 before it would bog out. I'm no expert, hints why i'm here, but really don't think its a drive problem. The carb really does seem a likely source. i know it needs work. Same goes with fuel, I tryed to pump as much of the old fuel out that i could. got about 13 gal. out of it. then replaced it with fresh fuel and changed filter. can i run an external tank? mabey, cutout under the seat were the built in cooler is and put a smaller tank in there?


QC: to be more specific, it did not rev up once it "slipped" or "bogged out". It did act like it wanted to stall but pulled it back to neutral before it could.

 

[erikgreen]

Re: 15mph then nothing?

How long can you drive it at low speed? Forever?

It sounds like a restriction somewhere is keeping the needed amount of fuel from getting through at higher speeds, or possibly a weak/near failure fuel pump.

I'm with the other guys - clean the tank, anti-siphon, fuel lines, filter, water separator, and carb.

Erik

PS And check the fuel pump overflow for gas

 

[Fishermark]

Re: 15mph then nothing?

You might try hooking up a remote fuel tank and see if that solves your problem. (Just a typical six gallon tank for outboards will work). If that solves the issue, then you can narrow down the problem. You also need to install a fuel / water separator like the one pictured here:

 

[BUMP]

Re: 15mph then nothing?

erikgreen : Yes sir, i can go all day long at 15 MPH. I do think it's a fuel problem also. What/were exactly is the " fuel pump overflow"? I did replace a clear hose that ran from the back (towards engine) side of the pump to the back side of the carb. The original hose was completly glogged.

Fishermark: I would be interested in looking into that remote fuel tank if they aren't to pricey. I wouldn't doubt there could be tons of crap in the tank. it is built in so i can't see any way to clean it out. If it doesnt work then i guess I would have to point fingers at the Fuel pump and/or carb. I do have a water/fuel seperator on it already. I called around for the fuel pump, 2 places quoted me 212 bucks, they say its a vintage pump..

 

[Fishermark]

Re: 15mph then nothing?

Just to clarify - I suggested the tank just as a temporary measure to help identify the problem. They're not too expensive and can even be picked up at Wal Mart, etc. You might even be able to borrow one from a friend with a small outboard.

Just don't add oil to the gas.

 

[BUMP]

Re: 15mph then nothing?

I understand, temporary only...If it does clear up the problem, how would i go about have the tank cleaned?