Boat starts, but won't idle

[kidmet]

I cleaned my carb and rebuilt, replaced coil, did plugs and wires. I can run it at about 2500 RPM, but below that (idle) it stalls. I have an '85 reinell with a 5.0 Cobra OMC I/O. I do have one part on the carb that I couldn't remember the setting and for the life of me don't know what it is. Every quadrajet (it's a rochester) rebuild I saw didn't have this part. Pic below.

HELP! I think this is why I can't idle.

 

[wellcraft guy]

Re: Boat starts, but won't idle

Having the same exact problem... Keep an eye on my thread as well for possible solutions.

 

[kidmet]

Re: Boat starts, but won't idle

Having the same exact problem... Keep an eye on my thread as well for possible solutions.

Watched your video and mine sounds exactly the same. Keep me updated. I'm dying to get her on the water. Have you tried jumping the positive terminal on your coil to your positive on the battery? Heard that helped some people. let me know.

 

[HCMQA]

Re: Boat starts, but won't idle

I believe that is the accelerator pump. You need that.
Most of the carb problems I have seen were the opposite of yours. Low rpm was ok but higher rpm no good. In most all cases it was a problem with the carb.
Be very careful cleaning it when you have it apart. And make sure the float is set properly as there is a different setting for each year it seems.
Also make sure throttle cable is correct.

 

[kidmet]

Re: Boat starts, but won't idle

I believe that is the accelerator pump. You need that.
Most of the carb problems I have seen were the opposite of yours. Low rpm was ok but higher rpm no good. In most all cases it was a problem with the carb.
Be very careful cleaning it when you have it apart. And make sure the float is set properly as there is a different setting for each year it seems.
Also make sure throttle cable is correct.

I'll have to read up on setting the float. Not even sure how to do it. I also know I need the accelerator pump, but how many turns should I set it to? All the way in? Half in? all the way and then 2 turns out?

 

[kidmet]

Re: Boat starts, but won't idle

Float is set correctly. Also did more research, it's not the accelerator pump. Any other ideas?

 

[Renken1]

Re: Boat starts, but won't idle

That is the ONE part in a rochester quadrojet that it is NEVER to be moved. It is part of the "idle enhancement" if I remember right, and its factory adjusted for a certian engine and is recommended to not even remove it when cleaning/rebuilding.

 

[kidmet]

Re: Boat starts, but won't idle

That is the ONE part in a rochester quadrojet that it is NEVER to be moved. It is part of the "idle enhancement" if I remember right, and its factory adjusted for a certian engine and is recommended to not even remove it when cleaning/rebuilding.

Wonderful news. lol. Great. Do I just need to adjust until it runs right? Google search brings up nothign about this idle enhancement screw.

 

[kidmet]

Re: Boat starts, but won't idle

I am flat out of ideas. Went from adjusting the screw to fully seated to one turn in. No change. jumped the positive terminal of the coil to the positive terminal on the battery. New plugs and wires. New coil.... rebuilt carb. Dipped carb in carb cleaning solution (for about an hour). New Starter, new fuel pump, New float, sprayed around the carb with carb cleaner, no vacuum leaks.... Why won't my boat idle? Any other ideas? I am stumped.

 

[Celtichawk]

Re: Boat starts, but won't idle

Those adjustment screws on the bottom of the carburetor turn those out 3.5 turns each. Turn all the way in then back them out 3.5 turns. Make sure flame arrester is tight. That's it for now your missing something and sounds like a easy fix.

Does boat run fine when not idle? As in does it take gas and not bog down?

 

[Celtichawk]

Re: Boat starts, but won't idle

Are you located in Southern California perhaps? I would offer my assistance in rebuilding it but if not sorry.

 

[kidmet]

Re: Boat starts, but won't idle

Are you located in Southern California perhaps? I would offer my assistance in rebuilding it but if not sorry.

I'm in Denver, CO unfortunately. But, to answer your earlier questions, yes, the boat runs great at 2200 RPM and above. No bog, no misfiring, nothing. I will try the mixture screws

 

[Bondo]

Re: Boat starts, but won't idle

I'm in Denver, CO unfortunately. But, to answer your earlier questions, yes, the boat runs great at 2200 RPM and above. No bog, no misfiring, nothing. I will try the mixture screws

Ayuh,.... It sounds like yer carb rebuild, Failed,...

It sounds like the idle circuit in the carb is Plugged,...

 

[kidmet]

Re: Boat starts, but won't idle

Ayuh,.... It sounds like yer carb rebuild, Failed,...

It sounds like the idle circuit in the carb is Plugged,...

I have zero prob opening her up Again. Anyone hav3 a diagram of where the idle circuit part is so I can pay particular attention?

 

[Bondo]

Re: Boat starts, but won't idle

I have zero prob opening her up Again. Anyone hav3 a diagram of where the idle circuit part is so I can pay particular attention?

Ayuh,..... Lots of Info,... rebuildin' instructions appear 'bout 2/3s the way down the page,...

 

[Celtichawk]

Re: Boat starts, but won't idle

PM me I have rebuild diagram

 

[kidmet]

Re: Boat starts, but won't idle

Ayuh,.... It sounds like yer carb rebuild, Failed,...

It sounds like the idle circuit in the carb is Plugged,...

Well, looks like you were right on. Even though I soaked the carb over night, the circuit must have still been plugged. Read up on plugged idle circuits in rochester carbs specifically and learned a new trick. Boiling the carb (disassembled) in white vinegar. Did it and the boat idles. I adhusted unknown screw to a little below the surface of the carb and it seems fine. Thanks for everyone's input. Problem solved