175 Johnson will not idle

[Jonboy2542]

I will start from the top,
I replaced the stator recently, along with that I replaced the rectifier since I was informed that it would be better to replace with the stator. Now before replacing the stator it would somewhat idle. I decided to check the carbs after a rebuild and I have the floats adjusted wrong. I now have them adjusted per the manual (float height is level with gasket with carb inverted) I can start the motor and it will shut off after a few seconds. I can push the key in and the rpms will raise but it would still shut off, just longer till it does. What could be the issue? The carbs have been rebuilt and cleaned thoroughly. Its strange the it idled before


It is a 96 175 Johnson Fast strike. Model number is J175GLEDB.
It will not staying running if you pump the bulb.
I can keep it running if I push the key in every so often.

Spark is good, compression is good, carbs were cleaned twice. I adjusted the float bowls to spec. I set everything up by the manual. I doubt its the VRO pump just because it worked fine before and I put my hand over each carb while running and fuel comes out.

Idle mixture screws are turned out 5 turns. I tried going out a 1/4 turn but didnt really change much.


I tried a few things late last night and it will run on a cold start. As soon as it warms up and idles down, it starts to shut off unless I push the key in. I tried pumping the primer bulb and it doesnt help at all. The only thing that keeps it running is pushing the key in. I ordered a rebuild kit for the solenoid because it is leaking slightly when you push the key in only. But could that actually cause the motor to shut off when its warm?

[omcforever]

Did you use 6 new OMC/BRP kits/gaskets/seal for rebuild and where they rebuilt before or after problem occurred?

[Mattsuey]

i had a similar issue on a 93 GT200, it ended up being the fuel line from tank to thru hull fitting ,it was so degraded from the ethanol in the fuel that it wouldn't even hold for a vacuum test. once i replaced that fuel line it starts,idles and runs way better than it ever had, and i owned that boat/motor for 15 years

[Jonboy2542]

I did use 6 new OMC kits.
The problem actually was partially before. I bought the boat this year and when I first took it out, it would bog down when trying to get on plane. I kept pushing the key in and it would plane. So I rebuilt the carbs and did so by the factory manual. I took it out after that could barely get it to run. This time after searching and some testing, I found out that the stator was bad. The residue was a giveaway. Its kind of hard to say when the problem actually started.

But, I will say before I replaced the stator, it would idle no problem.

I don't think its the fuel line only because I have an inline fuel filter and I can see the fuel flowing

[wareagle24]

You may see gas flowing through the filter at idle but the hose could be collapsing whenever you apply more throttle to it.

[Jonboy2542]

You may see gas flowing through the filter at idle but the hose could be collapsing whenever you apply more throttle to it.

But I am having issues with idling.

[316jughead]

OK, on the carbs. Float levels are set with the gasket off, parallel to the carb gasket surface. Do not place a nylon washer under the needle seat. All carbs must be closed at idle and the timing must start to advance as the carbs start to open. Is there a clear or yellowing plastic sleeve on the small black carb roller? No misaligned carb o ring gaskets? Most of your year motor idled better with 51/2 to 6 turns out on the idle screws. Check for good spark on all cylinders as per the manual.

[wareagle24]

But I am having issues with idling.

Oh ok. Have you taken the boat out since the rebuild to see how it will do at half or full throttle? Years ago I had an older Johnson that wouldn't idle very good and would shut off if you gave it throttle to get on plane. Turns out it was my fuel line collapsing.

[Jonboy2542]

OK, on the carbs. Float levels are set with the gasket off, parallel to the carb gasket surface. Do not place a nylon washer under the needle seat. All carbs must be closed at idle and the timing must start to advance as the carbs start to open. Is there a clear or yellowing plastic sleeve on the small black carb roller? No misaligned carb o ring gaskets? Most of your year motor idled better with 51/2 to 6 turns out on the idle screws. Check for good spark on all cylinders as per the manual.

I know the float levels are correct. About the nylon washer; I will check them all just to make sure. There is a clear plastic sleeve on the carb roller. Saw that in another post you made so I replaced it. O ring gaskets are good. I will turn the idle screw out just a little more.

[Jonboy2542]

20191204_172154.jpg20191204_172154.jpg

[Jonboy2542]

20191204_172126.jpgl

[twitch]

Doesn’t look like there is a plastic sleeve over the that roller in those pics or I’m I not seeing correctly

[Jonboy2542]

Yea there is a plastic sleeve. Picture isn't the greatest. But thanks for checking

[Jonboy2542]

20191205_204933.jpg

So the needle seat needs to look like the one on the left in the picture?

[316jughead]

20191205_204933.jpg

So the needle seat needs to look like the one on the left in the picture?

Yes, no washer. There is a washer in the BRP kit for your motor, along with other parts that are not used. The washer is not used with the plastic bodies.

[Jonboy2542]

Yes, no washer. There is a washer in the BRP kit for your motor, along with other parts that are not used. The washer is not used with the plastic bowls.

Thank you. Is there anything else that I need to check while I am taking them apart? Is it possible that I have a timing issue?

[Ranger VX]

Does his motor have a exaust pressure sensor ? I had an Evinrude that the sensor plugged up in the lower unit and would not idle good at all until I cleaned it out. Just asking ?

[Jonboy2542]

Does his motor have a exaust pressure sensor ? I had an Evinrude that the sensor plugged up in the lower unit and would not idle good at all until I cleaned it out. Just asking ?

I dont believe this motor has one. I think that is on some newer motors.

[Bassmeister]

That's on the DFI engines.....his is carbed..

[316jughead]

Thank you. Is there anything else that I need to check while I am taking them apart? Is it possible that I have a timing issue?

I meant to type plastic bodies not bowls, I have an excuse but I'm not telling. Make sure that the center gasket is on, and also the bowl gasket is off when adjusting the float level. Float drop one inch. I would set the idle screws at 5 1/2 turns out to start with, the manual may say 5 turns but we found out that didn't work so good. Counter clockwise, or out, richens the mixture. If it once idled good and you haven't changed the timing tabs, you should be good to go. One part that is most often overlooked is the Vapor Separator Tank and the little VST air pump, probably not your idle problem, but could be, they do need to be rebuilt.