Won't Start After Adjusting Idle

steelyonfly

Seaman Apprentice
Joined
Jul 25, 2011
Messages
47
1999 40HP Force - 40ELPT.
Today I removed carb, cleaned it all up, replaced gaskets, and needle jet under float, made sure the float was level with housing for bowl cap. After install it was running a little fast - I don't have a tach meter, but my tach on dash said about 900 RPM's as a best guess. Mixture screw was fine . . . set at 1-1/16 out from bottom. So I decided to try to adjust the idle screw which resulted in a lot of linkage adjustments. I thought I got it running great. Started right up each time, purred at about 800 RPM's, linkage returned the motor back to idle each time after I revved motor with the stick (used neutral button), no hesitation or roughness at all. So, I go back inside to cool off after standing in the sun for a couple of hours. 2-3 hours later I decided to take the boat to the launch and run her around to be sure all is ok. Bulb was pumped twice and then was stiff. Turn it over and the dad gum thing won't start! It barely started to catch but wouldn't even do that after the 3rd crank. Fuel filter was holding fuel. After about a dozen cranks, I pull the boat out and go home. Decide to take another try to start it. Trim the motor down into another garbage can with water above the cavitation plate. Crank her a dozen times and she won't start. As before the first couple of cranks seemed more promising than the others, but not significantly so. Any ideas what to do? I will try to get some pics if you think it will help.
 

scottmm73

Petty Officer 1st Class
Joined
Jun 9, 2012
Messages
261
Re: Won't Start After Adjusting Idle

Are you getting spark? Kill switch installed?

P.S. I do believe the idle rpms must be set with motor in gear not neutral.
 

jerryjerry05

Supreme Mariner
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May 7, 2008
Messages
18,072
Re: Won't Start After Adjusting Idle

NeutralRPM's about 1100 in the driveway. Warm,in gear,in the water about 800.
Do a spark check.Plugs not fouled? Do a compression test,just to eliminate any problems.
Then check the fuel pump diaphram.
It's possible the needle/seat is stuck?
Remove the carb and check the float/needle/seat.
Then if it all seems right/? Check the flywheel key.
 

steelyonfly

Seaman Apprentice
Joined
Jul 25, 2011
Messages
47
Re: Won't Start After Adjusting Idle

Idle was set when well warmed up, but I didn't set it when in forward gear. I think i can return everything back to wher it was before i started. i figured this is what i would do the next time i work on it. i did increase the idle scwew in further to increase idle when i got back home from the launch, but wouldn't start.

Spark plugs should be fine as they are only 4 weeks old and I've only run the motor in the yard. i'll check condition and spark and I will do a compression test before I work on idle and linkage.

Needle is new. Needle seat wasn't removed or messed with.
 

foodfisher

Captain
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Feb 18, 2009
Messages
3,756
Re: Won't Start After Adjusting Idle

:laugh:pretty cool, thanks for finishing the thread
 

steelyonfly

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Jul 25, 2011
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Re: Won't Start After Adjusting Idle

I wouldn't say I'm done. I'll let ya'll know what I find on plugs, spark, compression, etc. i may have more questions before I'm finished. If I get it running again I'll let you know, too. I know some of the threads can be like reading a book with the last page missing. Thanks all.
 

steelyonfly

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Re: Won't Start After Adjusting Idle

So far ... plugs not fouled, plenty of spark, compression for top cylinder is 145 w/o oil and 150 with a small dribble of oil, bottom cylinder is 150 w/o oil and 155 with oil. Does anyone think that the new needle being all metal instead of having a rubber tip could be a problem? Still it ran great yesterday. I have a fuel pump gasket kit that I thought I would do later, but maybe that will be next.
 

steelyonfly

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Jul 25, 2011
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Re: Won't Start After Adjusting Idle

Sorry about posting repeatedly like this, but I realized that I didn't even try to start the motor this evening. I just went out to the garage and cranked it once and it almost started. I cranked again and it stated right up. No priming of the bulb and no choke just turns of the key. I didn't want to run it more than a few seconds so I shut it off, but it sounded fine.

Now I don't know what to think was wrong. I guess I'll start it up tomorrow and run it to see how we'll it does. I just can't believe that it would have been flooded before. I will be back to let you know how it does tomorrow.
 

foodfisher

Captain
Joined
Feb 18, 2009
Messages
3,756
Re: Won't Start After Adjusting Idle

Hope you're not starting it dry. Impellers aren't fun to replace.
 

steelyonfly

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Joined
Jul 25, 2011
Messages
47
Re: Won't Start After Adjusting Idle

So, you want to know the final word. It starts, runs, and seems just fine. Glad I didn't do a bunch of unnecessary stuff or I hope not to get stranded on the water. Btw, I still seem to have an issue with the impeller working just fine and then not working after starting it a few minutes later, but that's another thread. I don't know what the issue could be for the non starting after going to launch or not peeing sometimes. Thanks everyone.
 

scottmm73

Petty Officer 1st Class
Joined
Jun 9, 2012
Messages
261
Re: Won't Start After Adjusting Idle

Does it have a hard time starting after going to launch? If so, this could be because of transport. If you lock you motor up while towing it, sometimes it could flood out, carbs empty into intake.
 

notsunkyet

Petty Officer 2nd Class
Joined
Jun 8, 2009
Messages
198
Re: Won't Start After Adjusting Idle

that happens to me too my 86/85hp will run fine in the driveway all day long hook it up to the trainer and bounce it to the lake and its murder trying to get her to start....
 

foodfisher

Captain
Joined
Feb 18, 2009
Messages
3,756
Re: Won't Start After Adjusting Idle

Backpressure in the water. Idle speed should be 750-800 in gear in water. Around 10-1100 in driveway on muffs. Proper cold start procedure also.
 

steelyonfly

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Jul 25, 2011
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Re: Won't Start After Adjusting Idle

I never thought about tilting/bouncing being the potential problem. I wonder if that is all it is. I do have a brace that the motor rests on tilting the motor up when trailering and there are a lot of bumps in the short mile I have to the launch. I'll pay attention to getting the motor level or nearly so before starting. May not be able to always do this at some launches, though. Thank you for your help and have a great Independence Day. Btw, my idle is now 800 (F) and 1000 (N).
 

steelyonfly

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Joined
Jul 25, 2011
Messages
47
Re: Won't Start After Adjusting Idle

Well, it runs great and added about 200 RPM's to 5400. No trouble starting and didn't use choke or pump priming bulb. Maybe it was just flooded. I think I'm ready to go. Thanks again.
 
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