Can somebody ID this piece? 1989 Force 125HP OB Dual Exhaust

[Jiggz]

I replaced my idle port exhaust boot and upon removal of the old one I found two pieces of black plastic tubes which looks like the one on the pic. It looks like it inserts to some kind of port but don't know which one. The engine has been running fine except for rough idling when in the water. It idles fine when on flushing device but as soon as it gets into the water the idling RPM goes down from 1000 RPM to 700 RPM in neutral. When in forward gear it goes down to 500 RPM. I saw the old boot leaking exhaust and concluded this could be the cause. So I replaced the boot and found this two plastic tubes inside the leg's exhaust. I have to test the engine on the water with the new boot. I'll post back but for now I want to have an idea where these two tubes go to. Thanks.

 

[celtic gelf]

Re: Can somebody ID this piece?

Re: Can somebody ID this piece?

the motor year, size, and model or serial number will help..

 

[jerryjerry05]

Re: Can somebody ID this piece?

Re: Can somebody ID this piece?

Inside the boot.Of the exhaust.
On the side of the motor is a part called the towershaft.That's where the idle is adjusted.
About 1200 in the driveway.
In gear and warm 750-800.
The air screws front/side of the carb might need adjusting.
Gently in to the bottom.Out 1 and 1/16th turns.
Then in gear in the water screw in till the motor just coughs or bucks/stalls.Then out 1/2 turn.
Reset the RPM and then do the air screws again.

 

[Frank Acampora]

Re: Can somebody ID this piece?

Re: Can somebody ID this piece?

Those two tubes go outside the exhaust downtube and inside the midleg. In order to replace them you need to remove the powerhead. The engine will run fine without them.

I believe that their intended purpose was to maintain the level of water around the downtube and thereby add additional cooling to the downtube, midleg, and exhaust. I alsao believe that they were added to help reduce exhaust blowing out the idle relief vent during off idle operation.

However, never having questioned the engineers, this is just an educated guess.

 

[Jiggz]

Re: Can somebody ID this piece?

Re: Can somebody ID this piece?

Frank,
Thanks a lot. I took the boat out on the water today and the idling has gone a lot better. In fact, even starting on the water is way better. So yes, the leaky idle port boot was the main culprit. As for the two tubes, I'll just keep them handy and check back if I ever have to remove the power head. As I was surmising, they probably insert between the powerhead exhausts to somewhere in the mid-leg. As you have mentioned it doesn't have any effect on the engine performance, so far.

 

[Jiggz]

Re: Can somebody ID this piece?

Re: Can somebody ID this piece?

Thanks Jerry. After replacing that idle port boot the idling was a lot smoother on the water. Yes, I have the idle set at around 1000 RPM on muffs and it stays the same on the water. At forward gear, idling, on the water it stays at 700-750 RPM. Well worth the $12 boot.

Thanks again.