idle diagnosis help on 92 Johnson Fast strike 150 J150GLENC

[Ogdog]

I previously posted a couple months back on this same motor http://www.bbcboards.net/zerothread?id=761332 and the dealership replaced powerpack which helped a bunch. I also ran decarb kit and have been running seafoam in with my gas as I'm just on my 2nd tank of gas since I bought it. Boat is running tip top, fires right up and idles fine when not in gear. My issue is when kicked into gear (either forward or reverse) the idle speed goes down and the motor doesn't want to staying running. If I throttle up to a little over 1000 rpm it will run and not die, under that it doesn't want to stay running. Compression is good on all cylinders. I do have to pump the bulb after I stop and fish for awhile but it seems if air in was an issue it wouldn't want to idle when not in gear either?

What do I need to look at on this? Thanks in advance!

[ChampioNman]

Were the idle issues there before the power pack change or after? RPM's in gear at idle?

[Ogdog]

It did seem the issue was there before the powerpack change as well. I'll run it this afternoon and see what the rpm's are at idle out of gear and then in gear.

Thanks

[Ogdog]

I see some of the thread got lost, I'm running the champion plugs and they looked good. I did try choking the motor when it started to cough and that did not help. I've ordered new plugs and will install just to be safe. What do I need to check next?

BTW rpm's at idle before warm up in neutral around 1000, after warm up about 900. rpm's once engaged in gear drop to around 600 at idle. Will run fine at 1000 rpms and up.

[ChampioNman]

1000-1100 RPM is about normal until the motor warms up. Then ~900 is what it should be at in neutral. Once in gear the RPM's will drop to around 700. Have your dealer check the idle timing and speed. Yes BBC lost some posts with the move. Also make sure the throttle roller and timing roller are set per the sticky that is posted above.

[tritico]

1000-1100 RPM is about normal until the motor warms up. Then ~900 is what it should be at in neutral. Once in gear the RPM's will drop to around 700. Have your dealer check the idle timing and speed. Yes BBC lost some posts with the move. Also make sure the throttle roller and timing roller are set per the sticky that is posted above.

ogdog....
did you ever figure out your issue? I have a 93 150 FS and am experiencing the exact same problem. Any help or feedback would be appreciated, about to pull my hair out.

thanks -

[316jughead]

ogdog....
did you ever figure out your issue? I have a 93 150 FS and am experiencing the exact same problem. Any help or feedback would be appreciated, about to pull my hair out.

thanks -

Do a search on this problem. I think you will find some help.