OMC cobra re-build

j_warren

Recruit
Joined
Jun 30, 2007
Messages
1
i recently aquired a 1989 bayliner capri with a 2.3 ford and an OMC cobra lower unit. the block was cracked so i replaced it, the lower unit had water in the oil so i re-sealed it. my problem....the boat runs GREAT...out of the water, once you put it in the water...the engine will idle all day long or even run at low speeds, (ie: no wake zones). once you try to get up to a slightly faster speed, the motor bogs down and seems to lose ALL power. wait...there is more, the motor began to get very hot and, as well as smoke from the crank case vent, followed by dying several times. we limped it back to the ramp, loaded it and took it home....where i conected the garden hose, started the boat and once again....in nutral, forward, reverse, low RPM's, high RPM's, it ran great, didn't heat up, no sputtering, no dying, nothing...i'm stumped, any one ever encounter something like this????
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Re: OMC cobra re-build

Welcome to iboats j warren. You've placed your question in the Beachcraft Forum. You need to post your outdrive question in the IO forum. Running gear in boats are not boat brand specific and you will find a wide range of experienced people who read and respond to questions in that forum.
 

Rob454

Chief Petty Officer
Joined
Oct 9, 2005
Messages
508
Re: OMC cobra re-build

Souds liek the timing is off. it may idle great and low RPM but as soon as you hit the throttle it overadvances the timing. Check and possibly restab the distributor. that should take care of the runing bad.

it could also be a cause for the overheating you are getting.
On the hose the water pressure form the hose is enough to keep the motor cool and youre not really under a load. Take off the raw inpeller cover and look and make sure none of the paddles are broken. if they are get a new one. make sure the thermostat is openiong and closing correctly and its not stuck.
Rob
 
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