0x66 150

[Keith Ohanesian]

So I've had my injectors cleaned flowed and new filters installed. Cleaned the vst filer. Cleaned the 02 and almost closed dog bone. New stats, pressure valve and spring. Also pulled the head covers and cleaned the cooling passages. (they looked pretty good).

So its a 99 Cobia 204cc 99 ox66 150 with a m15 black yamaha prop.

Today the alarms went off. Was cruising at 30mph and pushed it up to 39mph full throttle. After about 5 mins of running at 5400 rpm it went into limp mode. I backed it down and shutout off. Thats when the alarms sounded. A weird smoke was coming out of the exhaust. I pulled the pugs and they were dry. Five of them were white with no specs of aluminum on them. I put it back together and fired it up. No alarms and headed back in at idle then to 25mph after the oh shit moment. It seemed to be running very rich at low rpm and lean above 4k. Got back in and the plugs were wet with fuel. The compression check was 120 on all six. Thank god!!

My question is would the pumps create a richness at idle? I think not. I believe without putting the meter on it it needs an o2 but also find it weird that 4 holes are lean. 3 on one side and the bottom on the other. But the engine tank was full and the main tank had about a 1/3 in it. I couldn't figure out which alarm was going off. The arrow was only over the green.

I pulled the oil filter out. That was clear. I pulled the o2 out and a bunch of oil came out of the dog bone area. Like oil from a automobile oil change. They're all soaking now to clean the caked up crap out.

Also the hose from the oil tank on the engine and from the side of the block were not installed on the throttle body cover. Thats my bad from when I did the injectors.

Fuel pressure is good

[pstephens46]

Where is Postis? This is his engine!

[pstephens46]

So I've had my injectors cleaned flowed and new filters installed. Cleaned the vst filer. Cleaned the 02 and almost closed dog bone. New stats, pressure valve and spring. Also pulled the head covers and cleaned the cooling passages. (they looked pretty good).

So its a 99 Cobia 204cc 99 ox66 150 with a m15 black yamaha prop.

Today the alarms went off. Was cruising at 30mph and pushed it up to 39mph full throttle. After about 5 mins of running at 5400 rpm it went into limp mode. I backed it down and shutout off. Thats when the alarms sounded. A weird smoke was coming out of the exhaust. I pulled the pugs and they were dry. Five of them were white with no specs of aluminum on them. I put it back together and fired it up. No alarms and headed back in at idle then to 25mph after the oh shit moment. It seemed to be running very rich at low rpm and lean above 4k. Got back in and the plugs were wet with fuel. The compression check was 120 on all six. Thank god!!

My question is would the pumps create a richness at ideal? I think not. I believe without putting the meter on it it needs an o2 but also find it weird that 4 holes are lean. 3 on one side and the bottom on the other. But the engine tank was full and the main tank had about a 1/3 in it. I couldn't figure out which alarm was going off. The arrow was only over the green.

I pulled the oil filter out. That was clear. I pulled the o2 out and a bunch of oil came out of the dog bone area. Like oil from a automobile oil change. They're all soaking now to clean the caked up crap out.

Also the hose from the oil tank on the engine and from the side of the block were not installed on the throttle body cover. Thats my bad from when I did the injectors.

Fuel pressure is good

Can anyone elaborate on the effect of not connecting hoses as this op explained in last paragraph?

[pstephens46]

Were the two hoses not connected dumping oil into the pan of engine?
Could this have created a low oil pressure alarm?

Have you tried to run it since connecting the hoses?

I don't know enough about this engine.

[Keith Ohanesian]

No I have not. I pulled the o2 out to clean it again. It was soaked with oil. The strange thing is 5 plugs white and the one plug that the o2 port comes off is dark.

[rodbolt17]

the hose from the oil tank to air box is simply a vent line.
the hose from the intake to the air box simply drains any collected spit back and burns it.
the O2 sensor voltage needs to be checked after cleaning or cleaning is useless.

[Keith Ohanesian]

Thank you. Its raining up here. I'll do it first thing tomorrow.

[Keith Ohanesian]

Ok so i was only able to get it while tied up. It didn't look good on the water today. With the engine warmed and at idle 600rpms with my finger over the hole on cylinder 1 the volts went from .35 to .38. There really was no movement.

Rodbolt, Ive read some of your replies to others and have assumed that the o2 is bad because the voltage doesn't move. Also I feel the ecm is in a bypass mode because its very rich at idle and extremely lean above 4k which is why it heated up. Ive also noticed its been using a lot of oil and fuel *****ing.

Thank you for your time also

[pstephens46]

Thank you. Its raining up here. I'll do it first thing tomorrow.

Where is "up here"? Mid Atlantic?

Take it for a good test ride and see what happens. Let us know.

[Keith Ohanesian]

In the Hudson Valley NY.

[Keith Ohanesian]

So with the new o2 after it warmed up it went .6 and didn't really change with my finger over the hole. It did seem to idle better and at low speed leaving the marina sounded crisper. It wasn't chugging at low speeds. The throttle seemed smoother going up on plan. Theres about 4ft chop today so Went about a half mile turned around. That was a pounding.